Archive through October 01, 2007
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New member Username: Derek19Post Number: 2 Registered: Sep-07 | What does the term efficient speakers mean? If I have a 50W amp (nad) what is the speaker spec. I should look for to make sure my amp can drive the speaker? Thanks, DD |
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Silver Member Username: DavidpaPortland, Oregon US Post Number: 472 Registered: Nov-05 | a 50W amp will drive any speaker. But if you mean drive loudly, even efficient speakers wont get too crazy. Efficient is how easy the speaker is to drive. An 8ohm speaker is easy to drive, and will play louder at the same volume settings of a 4, or 6 ohm speaker, and will not strain your 50W amp too much. 6ohm, and 4ohm speakers are tougher loads, and perform much better with more powerful amps(I'm speaking at higher volumes), but can still be paired w/ a 50W amp, you just wont get the volume out of them with the same amp, and, at higher volumes, the amp will struggle, and speakers will distort sooner. Theres more to it, but that is the simple version. |
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Silver Member Username: StefanomVienna, VA United States Post Number: 958 Registered: Apr-06 | Efficiency of a speaker is typically determined by the sensitivity spec. This tells you the output of a speaker with a 2.83 volt input (1 watt at 8 ohms; 2 watts at 4 ohms). Unfortunately, there is no standard for reporting this number. Some manufacturers report the number from an anechoic chamber, while others report more optimistic in room numbers. As such, comparing the number Paradigm cites to what B&W cites may not be making a fair comparison. This number combined with the impedance curve of the speaker in question along with its phase angle curve will determine how easy it is to drive. Speakers that dip low on the impedance curve demand more current than those that don't simply put. Odd phase angles put further strain on that. Note the impedance curve is not the single number that manufacturers put out. It may have nothing in common with the mfrs spec. The spec may be a bold faced lie. As far as what your NAD will drive, that depends on how loud you want it to be. In terms of phase angle and impedance, or as others would put it, the NADs ability to put out current, most NAD amplifiers are fairly robust, and are designed to drive reasonably difficult loads. That said, for *best* results, you might want to stick with speakers that don't dip below 4 ohms on the impedance curve, and aren't too spastic in terms of phase angle. I would also try to keep efficiency to 88dB or higher. |
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Silver Member Username: DmitchellOttawa, Ontario Canada Post Number: 287 Registered: Feb-07 | Derek, which NAD amp do you own? I'm guessing if it's rated at 50w it's an older model. I have an old 2150 (rated at 50 watts - an honest 50 watts from what the repair technician told me) that will drive pretty much anything I own. I wouldn't worry about it too much. Does it sound good? That's all the really matters.... |
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New member Username: Derek19Post Number: 3 Registered: Sep-07 | Thank you for the input. I'm learning and all the info has been great. By the way my amp is the NAD 325BEE. |
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Silver Member Username: DmitchellOttawa, Ontario Canada Post Number: 288 Registered: Feb-07 | No worries Derek. I'm still learning too! |
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Silver Member Username: GavdawgUpstate, New York Post Number: 891 Registered: Nov-06 | same here... I have not had experience with NAD in a while, but my 50WPC Rotel never broke a sweat when driving my maggies. I also didn't crank it up. In case you don't know, magnepans are usually classified as being of the more difficult speakers on the market to drive, with a 4 ohm load and low-ish sensitivity. |
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Silver Member Username: SkeeterheadPost Number: 131 Registered: Jul-07 | In simple terms: how loud will it play given a certain level of power feeding it. Less power and louder=more efficient. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11296 Registered: May-04 | . As usual ignore wiley. He knows nothing and is all too willing to share his ignorance. Efficiency and sensitivity are often interchanged and mistakenly used one for the other. They have little to do with each other and should not be used synonyms despite this common practice. When discussing speakers, efficiency refers to the amount of acoustic energy lost (usually as heat) when electrical energy is applied to a transducer. A transducer is a single driver (a "speaker" such as a woofer, midrange or tweeter) which takes one form of energy (electrical) and converts it to another form of energy (acoustic). A microphone is a transducer which converts mechanical/acoustical energy into electrical energy and is the analogous part to a loudspeaker at the beginning of the recording process. A turntable's phono cartridge is also a transducer for the same reason. Most drivers are less than 5% efficient meaning they waste approximately 95% of the electrical energy applied to their voice coils or motor systems while producing only 5% or less acoustic power for the voltage input. Most consumer speakers average only about 1-2% efficiency. This percentage of efficiency is seldom quoted because it is so low as to make most speakers indistinguishable from one another. Ideally, this efficiency specification should only apply to a raw driver and not to a complete speaker system which includes a crossover since the crossover components waste a large amount of the energy put into the system. Once again this is typically not how "efficiency" is applied. Sensitivity is a useful term to describe the specified output for a speaker system (or a simple single driver) when a given amount of power is applied to the system or driver's inputs. Therefore, a sensitivity specification should provide the acoustic power (dBw) when either one watt or 2.83 volts are applied to the system. Since speaker systems can vary in impedance and current requirements, the voltage input is preferred over the wattage input in order to more closely reflect the real world conditions of a non-constant impedance load. A low sensitivity speaker will not play as loudly as a high sensitivity speakers when the same amount of power is applied to the system inputs. The industry average is approximately 87-88dB output measured at one meter distance with 2.83 volts applied. Each three dB increase or decrease in system sensitivity indicates the gain or loss of what would be half or twice the amount of power. Maintaining a 50 watt output capacity, switching from a 88dB speaker to an 91dB speaker would be the rough equivalent of switching to a 100 watt amplifier. Switching from a 88dB speaker to a 85dB speaker would be the rough equivalent of going from 50 watts to 25 watts. If you are looking for high volume levels, it is easier to buy high volume (SPL's) in your speakers than in your amplifier and you should look for the highest sensitivity speaker system you can afford. Sensitivity specifications are, however, quite liberally quoted and the on paper numbers do not reflect the "difficulty" an amplifier will face when asked to drive any particular speaker system. Low impedance loads are more difficult to drive than high impedance loads. Difficult phase angles are the result of crossovers with high inductance or capacitance and will make life more difficult in most cases for any amplifier. System sensitivity is a very broad number that can be far more misleading than helpful in many cases. After all is said and done, however, if someone tells you a speaker is "efficient", they probably mean it plays at high volume for any given amount of power. They are being very lazy and inaccurate in their choice of words but that is in all likelyhood what they are trying to say. http://www.enjoythemusic.com/audioterminology.htm#S . |
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Silver Member Username: StryvnPost Number: 480 Registered: Dec-06 | I think that's what wiley was trying to say, Jan. Naw. He's too stupid to strings those words together in that order. Instead, "when paired with the wrong speakers, the receiver will go into premature clipping." came out. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11298 Registered: May-04 | . LOL, LOL, LOL, etc., etc., etc., ROTFL! |
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Silver Member Username: SkeeterheadPost Number: 132 Registered: Jul-07 | There they go again.Using a million words to add nothing of substance-Jan and his band of idiots. |
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Silver Member Username: GavdawgUpstate, New York Post Number: 902 Registered: Nov-06 | Wiley... How 'bout you take a handful of quarters down to your local laundromat and take out your aggressive nature on the spin cycle...eh? Let me know if it helps. |
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Silver Member Username: SkeeterheadPost Number: 134 Registered: Jul-07 | You call it aggression a la Vigne. Actually, it's just common sense. Don't you think it's time to cut the apron stings, Gavin. Grow up. You don't need to hang on Vigne's every word like he is some infallible prophet. Use your brain, man. I know you still have a few wrinkles up there somewhere. Vigne hasn't totally smoothed them out, has he? Power to the people! |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11301 Registered: May-04 | . Dennis Michael Wiley Silver Member Username: Skeeterhead Post Number: 128 Registered: Jul-07 Posted on Tuesday, September 18, 2007 - 02:11 pm: Jan is correct. You can go now, wiley. . |
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Silver Member Username: SkeeterheadPost Number: 137 Registered: Jul-07 | Only when you do, Mr. Perfect. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11309 Registered: May-04 | . Eh, you're kinda funny, wiley. Very stupid but kinda funny in a stupid kind of way. You're sort of the Pauly Shore of this forum. You can go now, wiley. . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11310 Registered: May-04 | . Unless, of course, you're ready to explain, " ... when paired with the wrong speakers, the receiver will go into premature clipping." |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11311 Registered: May-04 | . Wiley - Are you the result of "premature" something or other? |
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Silver Member Username: Mike3Wiley, Tx USA Post Number: 702 Registered: May-06 | Jan that post you have of DMW on that other thread is spot on. Funniest one I ever read. Still LMAO. A classic. Should have posted it here too. |
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Silver Member Username: SkeeterheadPost Number: 143 Registered: Jul-07 | Jan has another disciple. Watch out!!! People are really attracted to bull. Of course, that would only be a certain type of individual. |
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Silver Member Username: DmitchellOttawa, Ontario Canada Post Number: 297 Registered: Feb-07 | Yet another thread gone off the rails... |
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Silver Member Username: GavdawgUpstate, New York Post Number: 921 Registered: Nov-06 | Yup... thanks to Wiley. I can see his new email signature now... "Stumped by Tom DeVesto, CEO Tivoli Audio" |
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Silver Member Username: SkeeterheadPost Number: 148 Registered: Jul-07 | Gavin, read the thread. You blame me for hijacking it. Do you even read your savior Jan's posts or just see his name and assume all is right with the world? |
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Gold Member Username: NuckPost Number: 8703 Registered: Dec-04 | No, but very accurate in audio. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11322 Registered: May-04 | . I can't save the world from the likes of you, wiley. I try though and hopefully one day I'll succeed. |
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Gold Member Username: ExerciseguyBrooklyn, NY United States Post Number: 1314 Registered: Oct-04 | http://www.eugenicsarchive.org/eugenics/list2.pl |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11327 Registered: May-04 | . I couldn't find a picture of wiley in there. Suppose his image doesn't appear on film? |
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Silver Member Username: SkeeterheadPost Number: 151 Registered: Jul-07 | "Or, if it's easier, just tell us about your gigantic Radio Shack speakers in your single wide mobile trailer. How's your Mom feel about having to push her walker and oxygen tanks around those suckers? Bet she yells at you, huh?" Jan Vigne |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11331 Registered: May-04 | . Yep, that's what I said. Did I hit a nerve? |
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Silver Member Username: SkeeterheadPost Number: 159 Registered: Jul-07 | Yep. You did. But not the one you were aiming at. Instead, you simply confirmed what we all already know about you. You're an insensitive self-righteous a$shole. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11336 Registered: May-04 | . Amazingly, we needed no confirmation of our suspicions regarding you. And, wiley, you know what? I don't care if I hurt your widdle feelings. As if you have any. Go away. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11337 Registered: May-04 | . Stop posting, wiley. You've ruined enough threads for one day. |
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Silver Member Username: SkeeterheadPost Number: 162 Registered: Jul-07 | And you haven't, of course. What a sap. |
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Gold Member Username: Thx_3417Bournemouth ... Post Number: 4550 Registered: May-05 | It would be interesting thou to take one of those DIY 1W amplifier and play a heavyweight film like "Apollo 13" dts THX laserdisc though to see if it can survive the brutal dynamic of chapter 13. |
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Gold Member Username: NuckPost Number: 8729 Registered: Dec-04 | With some very efficient JBL or Klipch speakers, chapter 13 'the launch' would be interesting. I would think a 3 watt amp would move more air. I pour all 800 watts into that one! |
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Silver Member Username: SkeeterheadPost Number: 166 Registered: Jul-07 | Why would that be interesting Cocoon? The answer should already be obvious to a reasonably discerning poster. Oh, I forgot. Sorry. |
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Gold Member Username: TapemanNew York City in-HD, NY Post Number: 1511 Registered: Oct-06 | I think Jan gave a very good accurate description. I like to echo what Jan and Wiley said in a simple definition. Efficiency: Efficiency rating of a speaker is how well a speaker converts Electrical Power (in Watts)to Acoustical Power. Most speakers have a very low. Efficiency rating is measured in Percent (%)usually between 1% to 10% Sensitivity: A sensitivity rating tells you how effectively a speaker converts Electrical Power (in Watts) to volume (in Decibels). The higher the rating, the louder of the speaker will play with a nominal Power amplification. Sensitivity rating is measured in dB 2 very similar aspects but different measurement. |
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New member Username: SobeeatchPost Number: 3 Registered: Sep-07 | Wiley and King have excellent and helpful responses. Thanks. |
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Gold Member Username: Stu_pittIrvington, New York USA Post Number: 2104 Registered: May-05 | The latest incarnation of one Dennis Michael Wiley? |
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Silver Member Username: StryvnPost Number: 497 Registered: Dec-06 | Hey johnson, Where did you find this "excellent and helpful..." response from wiley? wiley has never said anything excellent or helpful. Neither in this thread nor these forums as a whole. Period. Unless "when paired with the wrong speakers, the receiver will go into premature clipping." is what you'd consider excellent and helpful. In which case, you and wiley belong together. Someplace else. Go away wiley. |
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New member Username: SobeeatchPost Number: 4 Registered: Sep-07 | Stryvn, you are just plain wrong. I have read many of his posts in audio and video and have found them to be very straight forward and helpful. More than I can say for a lot of the posters you seem to admire and follow around like a dog in heat. |
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New member Username: SobeeatchPost Number: 5 Registered: Sep-07 | Oh by the way, a low powered receiver may very well clip when paired with low efficiency speakers that it is unable to push. Wiley's right again. |
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Silver Member Username: DmitchellOttawa, Ontario Canada Post Number: 317 Registered: Feb-07 | This is just silly. |
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Gold Member Username: NuckPost Number: 8765 Registered: Dec-04 | Same old Wiley. Cant we ban his IP? |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11361 Registered: May-04 | . JJJ- And just how do you know wiley said anything about clipping? Just what thread did you find this in? wiley, it doesn't matter what name you use. I'll get you banned once again. The administrator banned you yesterday, wiley, and if it takes another round of complaints, I'll get you banned again. And we'll keep this up forever if necessary. . |
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New member Username: SobeeatchPost Number: 6 Registered: Sep-07 | Vigne, what is this obsession you have with Wiley? |
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Gold Member Username: NuckPost Number: 8769 Registered: Dec-04 | It is to have him booted permanently from the forum, as he has no ability to explain any of his outlandish spurts of wisdom. When wisdom is involved. It is usually a post to knock Jan and people who agree... See, since you have an opinion on Jans input already, JJJ, you must have read a bit on the forum...right? If you have not seen yet how Wiley is only a slimy spamming useless knowzero skuzzball, maybe you should read a little more before sounding strangely like the shitforbrains I just described. Hows that sweetheart? |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11364 Registered: May-04 | . JJJ- And just how do you know wiley said anything about clipping? Just what thread did you find this in? I asked first. Answer, please. Which thread? . |
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Silver Member Username: Nickelbut10Post Number: 467 Registered: Jun-07 | I have a feeling that JJJ knows Wiley in human form. Or lack there of. |
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Gold Member Username: NuckPost Number: 8771 Registered: Dec-04 | Personal Saturday night at the movies for first right hand carnal knowledge. |
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Silver Member Username: Nickelbut10Post Number: 478 Registered: Jun-07 |  |
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New member Username: SobeeatchPost Number: 8 Registered: Sep-07 | Vigne, I must disabuse you of the notion that you can demand a response from anyone in this forum. I am not Nuck or one of your other followers who jumps when you snap your fingers. You're nothing but a shallow creature masquerading as a human being. I owe you absolutely nothing. |
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Gold Member Username: NuckPost Number: 8783 Registered: Dec-04 | Ignore button. I suggest you use yours too, Wiley. Just like you suggested on the other thread. Live it man.I dare you to ignore me. |
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Silver Member Username: Mike3Wylie, Tx USA Post Number: 733 Registered: May-06 | OK we all now know JJJ is just another reincarnation of previously banned posters. It was obvious from "1800 is too much" on the "Am I asking for trouble thread". Time to nip this in the bud. How about we all just do what Mike B. suggested? Getting JJJ banned is a waste of all our time and effort. Just do what Mike B. offered. PLEASE! There I said please too. |
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Gold Member Username: Frank_abelaBerkshire UK Post Number: 2376 Registered: Sep-04 | In my view, sensitivity and efficiency go hand in hand. If a speaker is made to be more efficient, this affects its sensitivity in a good way. If a speaker is made less efficient, it affects sensitivity adversely. As Jan pointed out, efficiency in its truest form is a measurement in percentage terms and almost all speakers range between 1 and 3% efficiency. Since a minor change in efficiency means virtually nothing in these terms, it's more helpful to use sensitivity. Sensitivity is measured in db/w/m. Typically it's how much noise do I get from a complete speaker (not just a driver) at a distance of 1 metre if I supply it with 1 watt of power in the form of a 1khz tone? An average sensitivity speaker is about 87db/w/m. i.e. if 1 watt of power is supplied to it with a 1khz tone and you stand 1m away from it, you will hear that tone at a volume of about 87db with is slightly higher than typical talking volume. However, this doesn't take into account the impedance of the speaker, which is why Jan is quite correct in saying you need to be a bit careful with this. If you supply the same tone to a speaker with a rated 90db/w/m, it should supply a sound of 90 db, but if this speaker has lower impedance (say 4 ohms instead of 8), then it may sound the same or even lower. This is because power is directly related to the load it is driving. I prefer to think of speakers in sensitivity terms whiole bearing in mind their impedance as a separate thing completely. To me, a 90db/w/m speaker with 4 ohm impedance is the SAME or possibly more difficult to drive than an 87db/w/m speaker with an 8 ohm impedance. Keep both numbers in mind. So what does this mean for someone with a 325BEE? Well, we know that the 325BEE is not a high end machine, but it is a good machine. If you wish to be kind to the amp, because you think (relatively correctly) that it would benefit from this, you could ensure that the speakers have an 8-ohm impedance rating. This guarantees that although the impedance may dip, it won't dip below 4-ohms (that's the usual criterion) which makes it easier to drive. If the rated sensitivity is higher than 87db/w/m, then that just helps things even more. FWIW, I have had good results with the new Focal Chorus 700V range with this amplifier. This range are higher sensitivity than most and have a benign 8-ohm load. If you like their presentation, they could be just the ticket. Regards, Frank. |
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Gold Member Username: PetergalbraithRimouski, Quebec Canada Post Number: 2031 Registered: Feb-04 | Frank said: In my view, sensitivity and efficiency go hand in hand. Exactly, except than Jan Vigne wrote: Efficiency and sensitivity are often interchanged and mistakenly used one for the other. They have little to do with each other and should not be used synonyms despite this common practice. How can they have little to do with each other? How could one double the efficiency and not raise the sensitivity at the same time? If a speaker became 100% efficient, it would have little but to produce a given SPL at 1m at 1W since there is nowhere else for the energy to go. David wrote: a 50W amp will drive any speaker. But if you mean drive loudly, even efficient speakers wont get too crazy. I beg to differ. Do the math. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11380 Registered: May-04 | . "How can they have little to do with each other?" How? Because there is no direct, consistent connection between raising one and having a specific rise in the other. They are tied together in a fashion similar to enclosure volume and frequency extension. You cannot alter one without changing the other but a given change in one does not imply a specific change in the other. They are tied together like voltage and current are joined. You can change one and still have the same amount of work done. You're arguing semantics and the choice to be lazy with words,PG. Most particularly the two are separate items when discussing speaker system efficiency. . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11381 Registered: May-04 | . "If a speaker became 100% efficient, it would have little but to produce a given SPL at 1m at 1W since there is nowhere else for the energy to go." And what would the sensitivity of that system be? . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11382 Registered: May-04 | . "David wrote: a 50W amp will drive any speaker. But if you mean drive loudly, even efficient speakers wont get too crazy. I beg to differ. Do the math." You can "differ" but there's not enough significant information about the amplifier or the speaker to do any real math. As written, the statement is about as true as many others. Take a cheap 50 watt HT receiver with limited current connected to a highly capacitive 1.5 Ohm load. Do the math and figure out how loud the system will get if the speaker is 89dB "efficient". Not every speaker has to be 104dB sensitive to be considered efficient, PG. . |
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Gold Member Username: PetergalbraithRimouski, Quebec Canada Post Number: 2040 Registered: Feb-04 | How? Because there is no direct, consistent connection between raising one and having a specific rise in the other. Quite the opposite, it would be quite hard to raise the efficiency significantly without raising the other. Hopefully you know this. You say that I'm debating semantics, but you were very quick to jump on this Wiley person on what appears to be the same sort of semantics. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11384 Registered: May-04 | . What part of "specific" don't you understand, PG? Surely you're not that slow. Did you show up here to argue about words you don't understand and wiley? I have no interest in either. |
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Gold Member Username: PetergalbraithRimouski, Quebec Canada Post Number: 2041 Registered: Feb-04 | And what would the sensitivity of that system be? I haven't worked it out. I suppose it depends on the dispersion angle of that energy, and perhaps to a small degree the density of air (so temperature and humidity). Does that mean that I was wrong? For a given dispersion pattern and air density, I would think that 100% efficiency translates directly to sensitivity. If that's true, then there is more than a little relation between sensitivity and efficiency, don't you think? Someone could read the definition and sensitivity and that of efficiency, notice that they are a bit different and don't even have similar units, and conclude that there things are not related. But a physicist thinks about it for a few seconds to conclude that they must be related. It's strange that you jumped on Wiley for not realising the difference between the two terms, yet you gave David Pannell, the first to reply, a free pass. Yet David managed to interject the difficuly of driving a low impedance load in the equation, which is unrelated in some of the way he meant. |
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Gold Member Username: PetergalbraithRimouski, Quebec Canada Post Number: 2042 Registered: Feb-04 | You can "differ" but there's not enough significant information about the amplifier or the speaker to do any real math. Here's what he said: a 50W amp will drive any speaker. But if you mean drive loudly, even efficient speakers wont get too crazy. Even efficient speakers... In your post, you said: Most consumer speakers average only about 1-2% efficiency. Let's say 1% efficient and an average of 88 dB sensitivity (you said that too). Going 100-fold more efficient from 1% up to 100% would mean 108 dB sensitivity. (That doesn't look high enough to me for 100% efficiency, bet let's work with that.) So efficient speakers should be in the ballpark of around 108 dB sensitivity, otherwise they are not efficient, right? I'd say 50W into a 108 dB sensitivity speaker is going to be loud. It's going to be as loud as 5000W in a 89 dB sensitivity speaker (if if could take it). On what planet doesn't that qualify as loud then? So yeah, I think there's plenty of information to do some basic math. I just did. Do the math and figure out how loud the system will get if the speaker is 89dB "efficient". Not every speaker has to be 104dB sensitive to be considered efficient On the contrary. Earlier you said that the average sensitivity was 87-88 dB, so I doubt anyone would say that 89 dB would be "efficient". I think that around 104 dB is what you need to be considered efficient, or have you already forgotten the difference between sensitive and efficient? That's strange because you got very upset by the difference earlier. |
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Gold Member Username: PetergalbraithRimouski, Quebec Canada Post Number: 2043 Registered: Feb-04 | What part of "specific" don't you understand, PG? Surely you're not that slow. Have to result to insults already? That was fast. I know what specific means. Let me repeat with different words this time around. I believe that one could write an equation relating the efficiency to the sensitivity if the dispersion pattern and air density are known. That, Mr. Vigne, implies a specific one-to-one relation. See, I didn't even need to insult you to write that. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11385 Registered: May-04 | . Goodbye, I'm not in the mood for a conversation with anyone so willing to prove they can't comprehend what they read and so rude as to show up long after a discussion and wish to begin trouble. Consider yourself called a name since you fantasize about that happening. |
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Gold Member Username: PetergalbraithRimouski, Quebec Canada Post Number: 2044 Registered: Feb-04 | I have no interest in either. That's great. I'm certainly not forcing you or anyone else to respond. I hope that you don't have to resort to big fonts if you reply. You tend to do that when you get upset. Resulting to insults is basically an admission that you have no counter-argument. It's best to say nothing. There's no need to worry. I'm just visiting this evening and perhaps won't be back in the speaker section tomorrow. It's pretty slow here these days (I wonder why), and I have replied to the topics where I could contribute. |
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Gold Member Username: PetergalbraithRimouski, Quebec Canada Post Number: 2045 Registered: Feb-04 | You posted while I was typing, but I'm quite happy with the outcome! Forum threads outlive the moment in these days of google, so it's always a good idea to correct prior mistakes even long after a discussion has slowed. If that weren't the case, then the forum admins would archive the subject or simply delete it. I agree that it is inconvenient when someone finally contradicts you. But the fact is that the thread was only two days old when I added to it; hardly very old. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11386 Registered: May-04 | . You didn't need to insult me but you did. There was no reason to be rude but you certainly are. You didn't need to get the math wrong on the receiver but you did. There was no reason to obfuscate "what would the sensitivity of that system be" with fuzzy math that didn't add up. But you did. 108dB?! LOL At least you realize you pulled that answer out of your @ss. You should have been able to comprehend system efficiency but you can't. In which of those do you hold an advanced degree? You didn't need to justify your existence ... oh, wait, you do need that one. Thanks for not being here when I wake up. . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11387 Registered: May-04 | . "I have replied to the topics where I could contribute." See the above post. |
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Silver Member Username: Rysa3Houston, Texas Post Number: 228 Registered: Nov-06 | Jan's September 18th 2007 7:26 PM post should be required reading for anyone interested in or selling speakers and amplifiers/receivers. Excellent and well presented information. Thanks |
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Bronze Member Username: SobeeatchPost Number: 25 Registered: Sep-07 | Peter, you will never convince Vigne of his fallibility. It's a personality flaw he has yet to acknowledge. But some of us appreciate your info and persisitence. |
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Gold Member Username: PetergalbraithRimouski, Quebec Canada Post Number: 2047 Registered: Feb-04 | You didn't need to insult me but you did. By implying that you are not a physicist? You got all wound-up much before I wrote that. You got all wound up as soon as I pointed out the flaw in your logic in my first post. fuzzy math that didn't add up. But you did. 108dB?! So increasing the power by hundred-fold doesn't add 20 dB of SPL? You are being way too vague about what is wrong in my simple analysis. Vague enough to keep the support of your followers I suppose. At least you realize you pulled that answer out of your @ss. No need to be rude yet again. It's called a back-of-the-envelope calculation. We scientists do that sort of simplified analysis all the time before investing time on a problem. You should have been able to comprehend system efficiency but you can't. Sure. Right. In which of those do you hold an advanced degree? I only hold a batchelor of applied science in engineering physics. My Ph.D. is in a natural physical science where fluid mechanics plays a large role. I'm sorry if that disqualifies me from pointing out that you are wrong when you say that efficiency and sensitivity have little to do with each other. The fact remains: if you do not change the dispersion pattern of a loudspeaker, increasing its efficiency by 10-fold results in 10 times the acoustic power output, and an increase of 10 dB SPL output, and therefore a 10 dB increase in sensitivity. There. There's a one-to-one relation between the two. Yet you maintain that there isn't and that I don't understand the concepts. Ah well, I've written enough that people can make up their own minds about whether I know what I was talking about or not. Consider yourself lucky that you have supporters like Mark. |
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Gold Member Username: PetergalbraithRimouski, Quebec Canada Post Number: 2048 Registered: Feb-04 | But some of us appreciate your info and persisitence. Thanks JJ. I guess it's one vote of support for me, and one vote of support for Mr Vigne. It's a good thing that you chimed in. ;-) |
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Bronze Member Username: SobeeatchPost Number: 29 Registered: Sep-07 | Well balance is generally a good thing. Can't let folks be railroaded by Nuck, Vigne, Wodeck and others who have personal axes to grind. What could be more ridiculous than to start a thread to ban a particular individual by a person who is the king of insults? |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11388 Registered: May-04 | . "You didn't need to insult me but you did. By implying that you are not a physicist?" PG, your lack of comprehension is matched only by your level of social maturity. However, your ability to pathologically hold a grudge would be nearly unsurpassed if not for wiley. Your rudeness is similarly so. A speaker system at 88dB sensitivity is considered 1-2% efficient. Speakers such as PG's Klipschorns are considered approximately 10-12% system efficient at a stated sensitivity of 104dB with an assist from the room providing the last fold of the bass horn and partially accounting for the slight variable in the final efficiency value. If your numbers are correct, PG, how do you then increase the system sensitivity by four decibles and arrive at a 100% efficient system? Where did the other 88% efficiency come from in four decibels? Your view of efficiency is limited to on paper viewpoints which do not take into account the real world condition under which almost any consumer loudspeaker operates. If that is your scientific approach, then you should reconsider your methods. Your math does not add up and yet you insist it proves me wrong. I'm not going to restate the fact over and over again for anyone who just doesn't care to consider anything at odds with their own set viewpoint, but all 85, 90, or 100dB sensitive speaker systems do not play at equal volumes. If you doubt me, go to a review magazine that challenges such numbers to see just how much difference there is in the manufacturer's number vs. the real world. Go listen to a few speakers and compare their volume potential with various amplifiers. This constant obfuscation and avoidance of basic real world facts has dragged this thread into a ridiculous area that is all about argument and not at all about discussion. If the fact that I made the statement is your basis for objection, I see no reason to continue this process. wiley has nothing to say that backs up any fact other than he is obnoxious and has been banned from the forum on numerous ocassions. In almost all cases here, the poster's dislike for me seems to be the the only reason for the discussion to continue. PG, dragging wiley back into this thread is an indication of your maturity and thought process. My comments to or about wiley have nothing to do with the meaning of efficiency or sensitivity. You know nothing about what has transpired with wiley and yet you wish to employ a tactic of "the enemy of my enemy". Consider just how siding with someone who has been banned from the forum twice and still defies the rules of the forum under another guise should make you look. If your reason for challenging my statement is based on the humidity in the room, I think your reasoning is vacuous at best, absurb at the most gracious. You can bring all the inane and inconsequential tidbits you care to into this discussion but it won't change the facts. You are argiung something that needn't be argued and doing a poor job of the task. This is what I said at the beginning of the thread speaking of efficiency and sensitivity, "They have little to do with each other and should not be used (as) synonyms despite this common practice." Please, read it again and try to comprehend the statement. I did not say efficiency and sensitivity are divorced from one another and your argument that I did is incorrect if not just plain ignorant. I did say they are not synonymous. That should be clear enough for anyone to understand and should end this argument over semantics. Argue what's on the page not what's in your mind. . |
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Gold Member Username: PetergalbraithRimouski, Quebec Canada Post Number: 2049 Registered: Feb-04 | your lack of comprehension is matched only by your level of social maturity. I wonder how an unbiased reader would see it. I only posted because you selectively and immaturely jumped on someone. A speaker system at 88dB sensitivity is considered 1-2% efficient. Speakers such as PG's Klipschorns are considered approximately 10-12% system efficient at a stated sensitivity of 104dB with an assist from the room providing the last fold of the bass horn and partially accounting for the slight variable in the final efficiency value. If your numbers are correct, PG, how do you then increase the system sensitivity by four decibles and arrive at a 100% efficient system? Where did the other 88% efficiency come from in four decibels? I never mentioned Klipschorns or any specific model. I worked from your own numbers. I arrived at 108 dB using the numbers given, and even stated that it didn't seem high enough to me (That doesn't look high enough to me for 100% efficiency, bet let's work with that.) If that is your scientific approach, then you should reconsider your methods. Your math does not add up and yet you insist it proves me wrong. Yup, I do. Dispersion remaining constant, going from 1% to 100% efficiency provides: 10*log(100) = 20 dB That's 20 dB of increased SPL and sensitivity. If you think that 1% and 88 dB are correct, then don't get upset that 88 + 20 = 108 dB. I didn't provide the initial number. You read somewhere that Klipschorns had 104 dB sensitivity and 10% efficiency, which doesn't match up what 88 dB and 1%. But you don't have the math skills to understand how these things are related, so you get upset at me. I'm just a scientist with bad methods and I'm surely unaware of all the real-world factors can come into play. Don't worry, I see that behaviour all the time on forums. As for questioning my scientific credentials and scientific method... It's funny, I could say something like that to a class of 100 undergraduates in engineering and they'd write it down. I'd say the same thing on an anonymous forum and suddenly salesman and HT installers assume they know physics better and get all upset. If your reason for challenging my statement is based on the humidity in the room, I think your reasoning is vacuous at best, absurb at the most gracious. You can bring all the inane and inconsequential tidbits you care to into this discussion but it won't change the facts. You are argiung something that needn't be argued and doing a poor job of the task. Air density is a function of pressure, temperature and humidity. Air density has an impact on the mechanical energy transfer efficiency between a moving diaphram and the air. My poor job has gotten you all wound up. This is what I said at the beginning of the thread speaking of efficiency and sensitivity, "They have little to do with each other and should not be used (as) synonyms despite this common practice." They have a whole lot to do with each other. They are very much coupled. They are not synonyms but yet are often used interchangely by the general audio population. You only get upset at that when someone you don't like does it. You didn't jump on david pannell in his first reply when he also misused it. You didn't jump on Stephen M. when he used it as the definition of sensitivity. You jumped on Wiley. You should get off your high horse of proper maturity and etiquette and look at your own behaviour sometime. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11390 Registered: May-04 | . So, it's true, wiley is your guiding light on this thread. It is your reason for continuing along this same path. Comsider the enemy of my enemy approach with someone who has been banned twice, PG. Why do you suppose he was banned twice? You are not in good company. If this is how you prefer to make an argument, that's your decision. It does not change the facts of the thread. It is common knowledge most consumer speakers operate in that 1-2% efficiency range. It is not my number. You never mentioned K'horns but I did. (I wouldn't dare mention K'horns any other time since you are so paranoid that I may not like your speakers.) It is well known the K'horns operate at 10-12% efficiency. I am not going to look up the fact. If you wish to dispute the matter, prove me wrong rather than making even more specious comments. Saying I am wrong is not worth the effort it takes to type such tripe when you won't prove your accusation. K'horns are 10-12% efficient. If you truly believe your speakers to be 88-90% efficient, prove me wrong. Otherwise, please tell me where the extra 88% efficiency comes with only a four dB increase. . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11391 Registered: May-04 | . If we are to pursue this matter further, let's discuss effiency and sensitivity in terms of real world and not just numbers on paper. Neither efficiency nor sensitivity can be divorced from the electrical component of the system. Without a signal to drive the speaker there is no sensitivity or efficiency. Therefore, ... 1) Can someone explain how the two statements below differ? And what they imply about efficiency and sensitivity? "88dB/1 watt/1 meter" "88dB/ 2.83 Volts/ 1 meter" 2) Can someone explain just how "sensitivity" is measured? And what the term means? 3) Anyone care to explain how raditation pattern effects in room "sensitivity"? Electrical efficiency? How a dipole or omni-directional speaker will differ in room compared to a conventional monopole? What does that say about efficiency? 4) Would anyone like to explain why system resonance will effect system "sensitivity"? If so, why would a sealed enclosure have a different system sensitivity than a reflex system? 5) How does system sensitivity vary with listening position? 6) What is the difference between a voltage based paradigm for loudspeaker measurement and a power based paradigm for the same? 7) If you have a 96dB sensitive full range single driver speaker system, will it play equally as loud at one meter distance as a four way, multi-driver system with fourth order passive crossovers when both are used with a 100 watt solid state, transformer coupled amplifier? 8) Taking PG's numbers of 108dB as an indication of 100% efficiency, if we have a speaker capable of 112dB, have we found a new way to generate energy? If you answer these questions, you will begin to understand why efficiency and sensitivity are not synonymous. . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11392 Registered: May-04 | . PG - Putting numbers on paper doesn't prove you have better math skills than I do. The numbers must be correct and your calculations are not. Ask a math student if that's not true. Let me say it one more time, efficiency and sensitivity are not directly proportional any more than bass extension and enclosure volume are dependent upon one another. What problem do you have understanding that? Do you also believe that bigger woofers are "slower"? K'horns use 15" woofers, you know. . . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11393 Registered: May-04 | . Finally, for now, my initial post came after DP's and SM's. It was meant to be a clarification of their statements. If someone had provided a proper answer, I wouldn't be on this thread at all. That I chose to refute their posts differently than I did wiley's is none of your business, PG. It is simply your dislike for me and a grudge that you have held for months that has spurred you to contribute. wiley can say what he wants to say without your assistance. If you wish to maintain an air of "maturity" and "etiquette" on this forum, consider your chosen company, PG. There is neither to be found in your present choice. . |
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Gold Member Username: PetergalbraithRimouski, Quebec Canada Post Number: 2050 Registered: Feb-04 | K'horns are 10-12% efficient. If you truly believe your speakers to be 88-90% efficient, prove me wrong. I never said I believed that. That would be silly. It's much more likely that the 1% figure is a gross over-estimate for typical 89 dB-sensivity speakers, and that horns are more directional than typical 89-dB speakers (thus increasing sensivity by focusing the radiated acoustic energy into a smaller space), don't you think? This is part of the reason that i didn't mention any specific models. Going from the typical 89 dB speaker to a Klipschorn changes more than just efficiency, it also changes the dispersion pattern. I've already said that this is a variable in the relation between efficiency and sensitivity. 8) Taking PG's numbers of 108dB as an indication of 100% efficiency, if we have a speaker capable of 112dB, have we found a new way to generate energy? You're being silly again. No, you haven't found a way to generate energy, you have found that changing the dispersion pattern of a speakers affects the sensitivity at the measuring point. Do people really take you seriously? You are either making up these biased questions to get a rise out of people (namely me, but it isn't working), or you don't understand basic physics. |
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Gold Member Username: PetergalbraithRimouski, Quebec Canada Post Number: 2051 Registered: Feb-04 | PG - Putting numbers on paper doesn't prove you have better math skills than I do. The numbers must be correct and your calculations are not. Ask a math student if that's not true. OOOh! AAAh! Ask a math student. Good one. Again, you are being vague. Where is 10*log(100) = 20 wrong? Let me say it one more time, efficiency and sensitivity are not directly proportional any more than bass extension and enclosure volume are dependent upon one another. What problem do you have understanding that? When did I say they are proportional? First, there a log in there, so that's a problem right there. Why is it that some people think that if two factors are not related if you can't draw a straight line between them? And you're worried about my math skills? Do you also believe that bigger woofers are "slower"? K'horns use 15" woofers, you know. Is this a demonstration of your argumentation ability? Is there a relationto the topic at hand? |
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Gold Member Username: PetergalbraithRimouski, Quebec Canada Post Number: 2052 Registered: Feb-04 | That I chose to refute their posts differently than I did wiley's is none of your business, PG It's everyone's business. You did it in a public place. You talk a good game about maturity" and "etiquette", but you are quite selective about who you practice it with. I posted because you were brash and demeaning towards others in your reply, yet managed to get things wrong yourself. At no point did defending Wliey specifically come into play. |
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Gold Member Username: NuckPost Number: 8824 Registered: Dec-04 | pass the popcorn. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11395 Registered: May-04 | . It's not your job to stand up for wiley, PG, public forum or not. It's obvious wiley could contribute his own "defense". It is your dislike for me that drives this plain and simple. I notice you have nothing to say to wiley regarding, "There they go again.Using a million words to add nothing of substance-Jan and his band of idiots." Why is that? He insulted everyone who isn't playing an enemy of my enemy game. Everyone, PG! That doesn't bother you? Please, do not say it's because I started this. That would only prove your total lack of comprehension about what has ocurred on this forum in your absence and only make your intrusion into this affair all the more rude. Just say you don't like me, PG. Then you can leave. I can see you have nothing more to add to the efficiency/sensitivity debate now that you've posted, "They are not synonyms but yet are often used interchangely by the general audio population." Remember when I posted, "They have little to do with each other and should not be used synonyms despite this common practice"? PG, this follows a common thread when you and I get involved in one of these stupid call outs of yours. The longer you try to defend what you said, the more I will show you that I am correct. Then you'll get all p!ssy and leave. Why not save us some time? "I posted because you were brash and demeaning towards others in your reply, yet managed to get things wrong yourself." I'm sorry, where have you proven me wrong?! If your math is not reliable, you have not proven me incorrect. If you only wish to think your speakers are 90% efficient, then you have proven nothing. Your into your evasion part of our debates, PG. Try answering a few of the questions I asked rather than ignoring them. Then tell me how I'm wrong, if you can. You ain't done squat so far, PG! "At no point did defending Wliey specifically come into play." Seems at odds with, "I posted because you were brash and demeaning towards others in your reply ... " Come on, PG, it can't be both. . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11400 Registered: May-04 | . PG - You might want to read this post again; King Tapeman Posted on Tuesday, September 25, 2007 - 09:47 pm. Which speaker do you suppose he's referring to as operating at 10%? Just thought I'd help you prove me wrong again. . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11401 Registered: May-04 | . Hey, PG! Read this. David Mitchell Silver Member Post Number: 297 Posted on Thursday, September 20, 2007 - 08:58 am: -------------------------------------------------------------------------------- Yet another thread gone off the rails... Gavin Silver Member Post Number: 921 Posted on Thursday, September 20, 2007 - 11:37 am: -------------------------------------------------------------------------------- Yup... thanks to Wiley. See, PG, the folks that have been around here know wiley and know who sends threads into the dumpster. They know who's "demeaning." Pssssssst, it's not me. So, how ya feeling about this "brash and demeaning" crap now? Seeing a trend that says wiley isn't the best enemy of your enemy you could have teamed up with? Peter! He's been banned twice! Say you don't like me and then go. . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11402 Registered: May-04 | . "Dennis Michael Wiley Silver Member Username: Skeeterhead Post Number: 166 Registered: Jul-07 Posted on Tuesday, September 25, 2007 - 11:01 am: -------------------------------------------------------------------------------- Why would that be interesting Cocoon? The answer should already be obvious to a reasonably discerning poster. Oh, I forgot. Sorry. " OK! Nothing demeaning here. Let's move along, folks. Nothing demeaning to be seen here, let's move. C'mon, c'mon, c'mon! Nothing demeaning. Nothin' demeaning ... Ooops, sorry. So sorry. That's really demeaning. I wonder if anyone else who hasn't been here for a year - a casual observer - would think that's demeaning too? Ooooooooh, I sure would. . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11403 Registered: May-04 | . "Dennis Michael Wiley Silver Member Username: Skeeterhead Post Number: 159 Registered: Jul-07 Posted on Friday, September 21, 2007 - 01:14 pm: -------------------------------------------------------------------------------- Yep. You did. But not the one you were aiming at. Instead, you simply confirmed what we all already know about you. You're an insensitive self-righteous a$shole." Yep, "@sshole" isn't brash or demeaning. No wonder PG didn't bother to defend wiley. . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11404 Registered: May-04 | . It was then that wiley got banned for (at least) the second time, PG. Actually, not for that response though. The administrator was willing to let that response go. So, you can imagine how un-brash and un-demeaning the one was that actually got him canned. Did I mention he was banned for (at least) the second time? And did you notice he came back in violation of the forum rules the very next day? Yep, I can understand why you chose me to call brash. I'm a stinker! . |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11405 Registered: May-04 | . Here's some speakers that must be - what? - 97% efficient? http://www.guerrillaaudio.com/store/GuerrillaGuidetoGreatSoundPart3.html |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11406 Registered: May-04 | . 112dB headphones, PG. Small but if we got enough of them, we'd be able to sell the electricity back to TXU. http://rongwangda.en.alibaba.com/offerdetail/57294380/Sell_In_Ear_Headphone.html |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 11407 Registered: May-04 | . http://en.wikipedia.org/wiki/Loud_speaker Looks like we're making energy here; "A horn loaded speaker can have a sensitivity as high as 110 dB @ 2.83 volts (1 watt @ 8 ohms) @ 1 meter." "Typical home loudspeakers have sensitivities of about 85 to 95 dB for 1 W @ 1 m - an efficiency of 0.5-4%. Sound reinforcement and public address loudspeakers have sensitivities of perhaps 95 to 102 dB for 1 W @ 1 m - an efficiency of 4-10%. Rock concert, stadium PA, marine hailing, etc speakers often have higher sensitivities of 103 to 110 dB for 1 W @ 1 m - an efficiency of 10-20%." Am I helping you any, PG? . |
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Bronze Member Username: WattsssupBarrie, ON Canada Post Number: 88 Registered: Aug-06 | Was away from the net today. Did I miss anything? |
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Silver Member Username: DmitchellOttawa, Ontario Canada Post Number: 330 Registered: Feb-07 | I think Nuck was making popcorn... |
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Silver Member Username: StryvnPost Number: 512 Registered: Dec-06 | Andre listened to the White Stripes. I jammed Amused To Death again. And George Costanza pulled a golf ball out of a whales blow hole. Other than that, not much. |
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Gold Member Username: StefanomVienna, VA United States Post Number: 1012 Registered: Apr-06 | " Here's some speakers that must be - what? - 97% efficient? http://www.guerrillaaudio.com/store/GuerrillaGuidetoGreatSoundPart3.html" One might note they also fudge the definition of efficiency. |
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Bronze Member Username: WattsssupBarrie, ON Canada Post Number: 89 Registered: Aug-06 | Not much happenin round here then... |
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Gold Member Username: PetergalbraithRimouski, Quebec Canada Post Number: 2055 Registered: Feb-04 | I'm sorry, where have you proven me wrong?! If your math is not reliable, you have not proven me incorrect. You keep saying the math is wrong but haven't told anybody what is wrong about it. Only vague accusations. If you only wish to think your speakers are 90% efficient, then you have proven nothing. I have never stated that. You made that up. In my previous post, I even explained it again. Your into your evasion part of our debates, PG. Who's being evasive? You keep repeating stuff I never said until people start believing I actually said it! "At no point did defending Wliey specifically come into play." Seems at odds with, "I posted because you were brash and demeaning towards others in your reply ... " Come on, PG, it can't be both. It's quite ironic that you tried to burn me over coals earlier over the use of the word specific (recall: What part of "specific" don't you understand, PG? Surely you're not that slow.) I didn't defend him specifically, as in I didn't jump in to save my buddy. I jumped in because I saw you were abusing someone again. Here's some speakers that must be - what? - 97% efficient? 106 dB sensitivity. Could be around 15 to 20% like other horn-loaded systems. 112dB headphones, PG. Small but if we got enough of them, we'd be able to sell the electricity back to TXU. Repeating a falsehood again so people start believing it? Tell you what, if those headphone really output 112 dB at 1m with 1W then I'll give you $1000. Canadian or US, doesn't matter anymore. What's that? Did the great JV make a mistake in thinking those headphones really put out 112 dB at 1m rather than the small confines of an ear? Could that be? -- Here's possibly what's got JV up in knots: - Typical speakers are said to have around 1% efficiency and 88-89 dB sensitivity. - I said that, without changing the dispersion pattern, there is a direct relation between efficiency and sensitivity. - JV apparently denies this is possible. - I said that, without changing the dispersion pattern, increasing efficiency 100-fold results in a direct relation to sensitivity showing an increase of 20 dB. - JV says my math is wrong but doesn't say where. - A speaker with 88 dB sensitivity changed to magically be 100% efficient would work out to 108 dB (88 + 20 = 108 dB). Is this math wrong? It's a simple addition. - JV knows I must be wrong because 108 dB sensitivity at 100% efficiency means that my 104 dB speakers would be impossibly efficient. He hunted the net for example of sensitivity greater than 108 dB and came up with headphone (hint: they are not measured at 1m distance). - But there is no contradiction to resolve. I pointed out multiple times that the dispersion pattern affects the density of acoustic energy, and therefore sensitivity. He seems to have missed that several times. I also pointed out that 1% is a rough number only. Let try to resolve the discrepancy. - Start with 89 dB instead of 88 dB (He said 88-89 dB) - Assume the Klipschorn has 12% efficiency, that's an 11 dB gain over 1%. Math again, where is it wrong? - 89 dB + 11 dB = 100 dB - Now change the dispersion pattern of the Klipschorn to beam the sound into an concentrated area, and you might get 4 dB out of that. - There you go: 104 dB. How hard was that? Did it really warrant JV ranting on about creating enrgy out of nothing? There goes your king fellas. He's not so good with actual numbers after all. Why do I bother? I'll tell you why. If I told JV he didn't know squat about selling gear and making a profit from it, he'd rightfully say he's been doing that as a career for years and knows how to sell. Well put the shoe on the other foot. Do you really think I need a "math student" here? I have credentials to teach at universities and I supervise M.Sc. and Ph.D. student. So I'm not going to take the little insults from Mr. Vigne when he doesn't have a leg to stand on. |
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