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New member Username: Sam_of_chicagoPost Number: 1 Registered: 02-2004 | All, The "running-in" or "break-in" or "burn-in", when used in the electronics industry, is simply to weed out any defective parts during design and development period of a product. It certainly does not improve the function of any electronic circuit. There is nothing mechanical about it even to the atomic levels. There is nothing like, 'run this motor and the gears, belts or shafts will get smoother and friction free on use!!!....LOL Engineers perform Temperature and Humidity tests on new products to see if they are robust enough to withstand various operating conditions. Electronics do wear, but it usually does not have any practical effect even over the long term. The one exception is LEDs, which will gradually get dimmer over time. However, even there, they reach half brightness after about 10 years of continuous use. If you do have antique stereo equipment (from the 60's and older), then you definitely do have to worry about the age of the capacitors. The early capacitors were very sensitive, and will blow if power is suddenly applied to them after a long period of disuse. They can be reconditioned, however, by applying a low voltage AC signal to them, and gradually increasing the voltage until you reach the working voltage of the cap. There is a lot of stuff on this on the web. BUT, none of this applies to modern electronics. So, in short, Receivers and DVD players should not behave any different after the so called imaginary "running-in" or "break-in" or "burn-in" time. These are inaccurate theories invented and developed by insincere or less knowledgable sales guys, who, I guess actually mean "comon dude, keep the device at home for some more time" (and narturally you'll start to like the stuff you own)!! However, video devices like TVs do get fainter and worse with aging and extensive use. A CRT (picture tube, TVs or computer monitors) is coated from inside. Electron beams project on them from the rear, creating a nice bright image. Upon long extensive usage (several years) the coating loses some of its properties and hence the brightness/sharpness falls to some degree. Many of us have observed this when using a old monitor and new one. Plasma TV screens have their own cons. When these TVs are on for long durations and if some part of the video is not moving (eg. channel logos at corners of the screen) it leaves a permanent ghost image in that area. It is highly RECOMMENDED to turn off plasma screen TVs when you are not watching. Bear in mind, electronic devices do deteriorate with age (unlike DeBeer's diamond's ad : " a diamond is forever" ..!!) but, that takes few decades. So, the way your electronics perform when new, will continue to do so for several years. Hope this puts an end to the misconception of "running-in" or "break-in" or "burn-in". And somebody please don't tell me that they learnt this theory in some class at some school. That can turn Einstein restless in his grave! |
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Nobody Unregistered guest | Just want to say that "diamond is NOT forever"!! As the crystal structure of graphite is more stable than diamond (well, they are basically just crystal of carbon anyway) on the Earth surface, diamond will "deteriorate" with time and change into graphite! Of course, here we are talking about millions of years. :p |
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Anonymous | Speakers definitely have a break in period. |
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Sam+Of+Chicago Unregistered guest | Yes speakers do. |
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Silver Member Username: John_aPost Number: 272 Registered: 12-2003 | Sam, great post. Yes, speakers. That is all. And because they are partly mechanical devices. There is a thread under accessories where someone is claiming you have to break-in speaker cables. I just don't know where you start with views like that. Faraday, let alone Einstein, would have seen instantly what nonsense it is. |
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Bronze Member Username: GoosePost Number: 48 Registered: 02-2004 | The amount of snake oil that is poured liberally around audiophile products and practices never ceases to amaze me. When I bought some speakers a while ago they threw in some speaker cables. They were grey and flat, probably 16 or maybe 14 gauge, and reminiscent of 300 ohm TV antenna cable, with about 1cm between the conductors (low capacitance, but high inductance). These cables had an arrow marked on them, which the salesman insisted should point from the amplifier to the speakers, or the sound would suffer. The best part was that there was no polarity marked, which, aside from making them a bear to hook up (I didn't keep them), meant that even if there was such a thing as directional wire, there were still two different ways you could hook them up, with opposite current flows! I regret to say that the name of a reputable electronics manufacturer was emblazoned on these cables (begins with R, ends in L, has a T in the middle). |
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Bronze Member Username: BilldashillPost Number: 65 Registered: 12-2003 | Amps, integrated amps and speakers need a break-in period. Its a fact. Receivers to a lesser extent. |
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New member Username: Sam_of_chicagoPost Number: 2 Registered: 02-2004 | Jeff, for people's sake don't provide inaccurate information. Amps or integrated amps too use solid state electronics and passive devices that do not need any break-in period. Be aware that this forum is visited by, written to and read from by a lot of people who seek correct and accurate info/advice. Irresponsible comments written just for the heck of it without proven theories have bad ripple effects. Some poor guy can take it as correct info and it passes on thru word of mouth. Again, speakers are basically membranes that virate at extremely high frequencies (Tweeter - highest ~ upto 30KHz, mid-range a little lesser and the subs between 10~150 Hz)to they tend to change a little over time by losing some stiffness/rigidness of the material. BUT, Amps or other electronics don't change much. I hope responsible readers would agree with my opinion. |
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Silver Member Username: John_aPost Number: 275 Registered: 12-2003 | Jeff, I do think Sam is correct on the point in question. Even with thermionic valve amplifiers there was no break-in period. They took a minute or two to reach operating temperature. Maybe that could change with time. But transistors are solid-state. There is nothing in an amp/receiver that doesn't work up to specification (or not) first time. Sam, You are right about speakers. I was doubtful about speaker break-in until I blew up the tweeters in my Kef Coda IIs (it was my own fault). The copper wire leading into the coil had just melted, like a blown fuse. A Kef-recommended servicing centre simply re-wound the coils. When I got the speakers back and tried them, I was so disappointed. They sounded dull and lifeless, like a cheap low-fi speaker, my wife agreed. I thought I'd wasted good money on an incompetent service, and regretted not throwing them away and buying new ones. I put them into storage. We moved house, and I eventually rigged them up as second speakers, not for music, just to listen to the news. Over some weeks they gradually came back to life. Eventually they were good as new, if not better. All the shine, detail, and sparkle returned. I use them now as surrounds for our HT set-up. Goose, That is a great story about the the arrows but no polarity on speaker cable. Of course it is absurd. On another thread, some months ago, I suggested a good rule of thumb was that you are paying too much for cables if the insulation has arrows on, to indicate which way the music goes. People got angry and told me the screening has to be grounded at the source: it says so on a "monster" web site. When asked how the electrons know which end is the source, they said "well it's my money, and if I like arrows, who are you to tell me what to do?" |
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New member Username: Sam_of_chicagoPost Number: 3 Registered: 02-2004 | Goose, There is nothing called "+" and "-" currents when you plug into an AC outlet or hookup wires between a receiver and speakers. Ofcourse there are "positive" (holes) and "negative"(electrons) charges and their flow but, it is not be mixed up with our HT discussions. VOLTAGE does have polarity, like the one you observe in all batteries. Use it incorrectly and you may screw up a device. Current flow is not bidirectional in any case. (let me not dig deep into unusually rare situations when it could) So, there is nothing called polarity of a cable. Even the colors of wires (red, white, black or anyother) is nothing but to make it easy for a user to know which wire you are hooking up and there are some worlwide standards to use RED for phase and usually BLACK as grounds. These are interchangeable as long as one know which is what. But this might for a second confuse another person looking for standard color convention. CABLEs do not have polarity. They are just a medium of transportation of electrons(current). I'll write more on this later. |
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Bronze Member Username: GoosePost Number: 49 Registered: 02-2004 | Sam, I understand that wires do not have an intrinsic polarity. My point was that the manufacturer was claiming that there was a preferred direction for their cables, which is ridiculous. Even if such a thing was true, you would still need to know which of the two wires in the cable to connect to the red terminal on the amplifier to ensure that the current flowed in the desired direction. The fact that the manufacturer did not so mark the cable only makes further mockery of their claim. |
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Bronze Member Username: JordiePost Number: 37 Registered: 12-2003 | http://www.odysseyaudio.com/setup_tweak.html what do you guys think? |
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Silver Member Username: John_aPost Number: 282 Registered: 12-2003 | adrian, Nice link. Thanks. I agree that amps and receivers need to get up to running temperature. Different component inside have physical properties that depend on temperature, but even for capacitors the tolerance is pretty wide, often something like -5 C to +110 C. Also, the running temperature is different according to what you are playing. Odyssey make a good case for leaving your amp switched on. However, I think they over-state things with 'There are several factors that determine the extensive length of "break-in", such as charging of capacitors, establishing the electron flow on the PC board, cables, soldering joints, etc.' Capacitors take only seconds to charge up. 'Establishing electron flow' is for all practical purposes instantaneous. If it doesn't happen immediately with cables and soldering joints it is never going to happen at all. Poor soldering joints can be broken with extreme temperature changes, and electrolytic capacitors can dry out and fail if over-heated or left idle for long period. I will agree that it is a good idea to leave a unit switched on. Yes, there may be some value in leaving it on for long periods especially in the first few weeks. One thing is there is usually an internal, re-chargeable battery, which has often become at least partly discharged in storage, and it is good to charge it up fully in the first session. But most of these things are ways of letting faults show up early, or safeguarding against components spending too large a part of their life running at less than optimal temperatures. If this is what we mean by "breaking in" then I will retract, but I am still sceptical about any audible benefits. Goose, I am with you. As I understand it, the signal, whether analogue or digital, is a rapidly-changing difference in electrical potential between the two cables. "+" and "-" are arbitrary - not so with DC. In any case it seems nonsense to have arrows. The current that flows is negligible, and, anyway, changes direction at high frequency. If you do not distinguish between + and -, then there can be no meaning in arrows to show which way the signal is being carried. The reason + and - are there is to maintain phase between different channels. That is important. It does not matter if you connect black to + and red to - as long as you do it consistently for all channels. "+ = red" and "- = black" is just convention, to help us remember |
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Bronze Member Username: GoosePost Number: 50 Registered: 02-2004 | Does the current change direction at all? I ask in ignorance here, but I always assumed that the signal starts at zero and goes "up" from there, corresponding to sound pressure excursions in the original signal that the speaker is trying to reproduce. Any current generated would then flow in one direction only. Or am I mistaken? |
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Bronze Member Username: PetergalbraithPost Number: 15 Registered: 02-2004 | The current/voltage looks like a wave with the zero at the middle. Half of the voltage is negative and the other half positive. Half of the current is in one direction and the other half in the other. |
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Bronze Member Username: GoosePost Number: 51 Registered: 02-2004 | I know that this is true of an AC signal, but is it true of the amplifier output? The sound pressure that the system is trying to reproduce is presumably strictly positive. Or do musical instrument produce negative sound pressure excursions as well as positive ones? |
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Bronze Member Username: PetergalbraithPost Number: 16 Registered: 02-2004 | Look at the woofer excursion... back (negative) and forth (positive). Look at vibrating strings (back and forth). My old Nikko Alpha 220 amplifier is a DC amplifier (freq reponse from 0 to 100kHz) and it has a "Normal/DC" switch on the back. On normal, the input signal is filtered to remove any DC signal prior to amplification. You get less signal manipulation (and presumably cleaner sound) when switched to DC where that circuit is bypassed, but be very sure you don't feed it a DC signal accidentally because it will amplify it (and god knows how the speakers will like that). |
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Bronze Member Username: GoosePost Number: 52 Registered: 02-2004 | I guess that's the answer. If the frequency spectrum of the output signal is band-limited to exclude DC, then the mean of the time-series output signal must be zero, regardless of the input. Thanks! |
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Silver Member Username: John_aPost Number: 284 Registered: 12-2003 | Goose, Peter is correct, I believe. When the signal goes "up" in one cable, it goes "up" relative to the other, where the signal can just as easily be said to go "down" relative to the first. That's my understanding. All one analogue interconnect (or speaker cable) does is connect two pairs of terminals, so the changes in electrical potential (Voltage) between the two terminals at one end are the same as those between the two terminals at the other. Minus a bit for the resistance of the cable. I am no expert. If there are subtleties I have missed, someone please say. But the arrows on the insulation are [words not allowed on this forum]. Your story about the R*t*l cable is great. Getting the phasing right is essential. If you get it wrong, it is because the two conductors in one of the cables have got twisted compared with those in the other. Reconnecting so that the arrows go in opposite directions would not make the slightest difference. If I recall correctly, cables are "isotropic": anything they do in one direction, they do just the same in the other. |
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Bronze Member Username: GoosePost Number: 53 Registered: 02-2004 | The main value of the arrows was using the fact that they were only printed on one side of the flat cable to help me remember which wire was which when hooking them up. Since these cables connected a sub and a pair of satellites, there were 8 connections to be made. I was renting at the time, too, and I moved around a bit, so disconnecting and reconnecting happened more often than what might be considered normal. It has been irrevocably etched into my brain to hook them to keep "red on the left with the arrow on top and pointing away". |
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Silver Member Username: John_aPost Number: 285 Registered: 12-2003 | Nice one, Goose. My personal mnemonic is the letter "R" stands for "red" and "right". Perhaps "red on the left" is easier if you are politically inclined, or know that a red light identifies the port (left) side of a vessel! |