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New member Username: HezekiahPost Number: 1 Registered: Dec-12 | I have put this thread in the speakers sub-forum as I think the problem I have is a speakers issue, but please move to the Receivers and Amps section if you think this is the wrong place. The XTZ speakers I own in my 5.1 setup are two 93.21 satellite speakers, two 93.23 loudspeakers, and one 93.22 centre loudspeakers. I also own a Pioneer VSX-K Receiver and a BK XXLS400-FF Subwoofer. The problem I have is that the receiver turns off on loud points during films and games - I'm talking about things like gunshots or explosions, or parts of films where the musical score significantly increases. This is particularly apparent on Blu-rays through my PS3. Lord of the Rings for example causes my receiver to turn off at less than -30 decibels. Its also happened during games such as Gran Turismo and Uncharted, but generally I can play games at -25 decibels no problem. It's also happened though my Sky HD box on the odd occasion, but I can generally watch tv up to -20 decibels no problem. Interestingly music doesn't seem to cause a problem - I've never played a track on the speakers loud enough for the receiver to switch off. Has anyone else had this problem happen to them? The issue isn't with the sub because the receiver is switching off even when the sub is off. Any help would be greatly appreciated because this issue is really annoying, and watching Blu rays is impossible. Thanks |
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New member Username: HezekiahPost Number: 2 Registered: Dec-12 | I should also point out that alongside testing the speakers with the sub switched off, I have also disconnected the speakers one-by-one - but the receiver still switches off withi seconds of Lord of the Rings. Also I sent my receiver to an official Pioneer dealership for testing/repair (costing me £60) and they confirmed there was nothing wrong with it. The specs say all three XTZ models I have are 4-8 ohms. The Pioneer receiver specs say impedance at output level 6 ohms. Could this be an issue? I don't know a great deal about audio so any help would be greatly appreciated |
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Gold Member Username: MagfanUSA Post Number: 2957 Registered: Oct-07 | How long has this been going on? Sounds like the amp is simply not going to properly run the speakers. Will it run a PAIR of the speakers.....disconnect the rears / center? Is the receiver in an enclosed space? It may simply be getting too hot. Heat KILLS electronics and will adversely effect its lifetime. Not to mention cause such shutdowns as you describe. With speakerss rated at 4->8 ohms and a receiver rated to only 6 ohms, I'd wager I'm at least on the right track. Is there a back panel impedance switch on your receiver? Such a switch will limit the power supply and allow the receiver to protect itself without the drastic measure of simply shutting down. |
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New member Username: HezekiahPost Number: 3 Registered: Dec-12 | For several months now. I didn't notice it at first, but then again I wasn't watching many, if any Blu rays. The receiver switches off with only one speaker connected at moderate volume levels, and having the sub off doesn't change anything. No impedance switch that I can see, and here's a pic of the back: http://www.pioneer.eu/images/products/avamplifierreceiver/pioneer/vsx-920-k-back _large.jpg |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 17583 Registered: May-04 | . Where'd you buy this system? Did you listen to the receiver driving the speakers before you made the purchase? Have you contacted the retailer for after the sale assistance? Did they recommend a four Ohm speaker be paired with a receiver which states it is not intended to drive a four Ohm load? Have you checked the speaker cabling for any stray conductors or possible frayed insulation which might create a short circuit? You say this problem doesn't occur with CD's, only on BluRays and games. What's your guess as to why this is only happening on the BluRays and games? What's different about them that wouldn't be occurring with a music CD? . |
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New member Username: HezekiahPost Number: 4 Registered: Dec-12 | Hi Jan, I bought the speakers at Audio Sanctum who sold XTZ products to UK customers- they've since ceased trading however so any assistance would have to come direct from XTZ. I already had the receiver when I bought the speakers so I didn't do any testing beforehand. As I said previously, I'm not an audiophile - a few weeks ago I didn't even know what impedance was. I've checked the wiring and rewired each speaker so I don't think there any fray wires. Earlier today I tried LOTR with the speakers set to OFF and as I expected the receiver remained on, even with the sub set to its highest base levels. I tried some CD's and Blu rays through my PS3 earlier and here were my findings: When playing some bass heavy tracks on CD I could have the volume set at -25 decibels, and could turn the bass to it's maximum no problem. When I reached around -23 decibels the receiver would switch off regardless of bass levels. When watching blu-rays, I can watch at -37 decibels without the receiver switching off. At -35 it will switch off on the odd really loud scene. -30 is out of the question, even with the sub switched off. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 17592 Registered: May-04 | . Receivers shutting down are commonly the result of the amplifier's power supply simply not being able to keep up with the demands of the speaker for high amounts of amperage (current). AC coming from your wall outlet is composed of both Voltage and Amperage. Voltage has the potential for work to be accomplished while Amperage accomplishes the work. For work to be done both Voltage and Amperage must arrive at the load in synch. The typical crossover network found in a consumer loudspeaker pushes the two components out of synch - this is known as "electrical phase angle" - and less work is being done under these situations. When less work is being done at the load, the amplifier will work harder trying to accomplish that work. More work from the amplifier typically results in more heat from the amplifier which is the enemy of good sound. With me so far? Impedance is composed of capacitance, inductance and resistance. Impedance is defined as "the resistance to work being performed". As impedance drops in the load more current is required in favor of less Voltage. As impedance rises, the opposite is true. Voltage is fairly easy for more amplifiers to produce but current is only found in amplifiers with stout power supplies. Therefore, lower impedance loads are more difficult for many amplifiers since they do not have the ability to deliver high current on demand or for sustained time periods. This is a very common problem with mass market HT receivers where the emphasis has been placed on the number of features rather than the quality of the amplifier. Pioneer, Sony, Panasonic, etc. all fall in the category of mass market recievers which have a reputation for not being able to adequately drive low impedance speakers. According to the specs you've provided, your speakers drop beneath the recommended impedance load for safe operation of your receiver. More current is being demanded by the speakers than the amplfiier can deliver. To protect itself from destruction the amplifier will shut down rather than implode as more current is drawn from an already depleted power supply. By increasing the amount of bass response from the amplfier you are making the situation worse as more bass equals more current delivery - which your amplifier struggles to acomplish as is. More than likely the difference between CD and BluRay is the higher dynamic range of the latter format. Higher dynamic range also asks for more current which must be delivered as quickly as possible. The amplifier reads this situation as a short circuit and quickly shuts down. How to solve this problem? One of several ways. If it is only the front speakers which cause the amp to shut down, you can buy new front speakers with a more benign impedance load. Or you can buy a speaker selector switch with a "protection" device switchable into the load. This isn't ideal but it is typically a less expensive option than buying a new receiver capable of driving your speaker's load. In the mean time, don't crank the bass when listening to DVD's and BluRay's. As leo has suggested, make sure the receiver has as much free air ventilation as possible. In some situations a small whisper fan set on top of the receiver to draw air through the chassis can help. I suspect your problems are not going to be solved by that particular "fix". It would certainly appear you have a mismatch of receiver capability and speaker load. The only permanent fix is to replace one of those two components; receiver or speakers. Lessening the demands on the receiver or adding the "protection" device can only get you so far. . |
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New member Username: HezekiahPost Number: 5 Registered: Dec-12 | Thanks for taking the time out to explain that to me Jan. Given the choice, I'd rather not replace my speakers. Would adding an amp to my setup work? Could I connect an amp to my receiver, or directly to the speakers? I'm wondering if something would something like this would do do the trick?: Superfi - ROTEL RA10 INTEGRATED AMPLIFIER The specs say 'Amplifier power (watts)/: 40/ channel (8 ohm, RMS)'. Is that a no-no then given my 4 ohm speakers? Also found this Marantz: http://www.amazon.co.uk/Marantz-PM60...7139053&sr=8-1 Also, my speakers are set to small. In terms of the crossover, I've always had this at 80Hz. Is that the standard setting for my type of setup, or is it something I should experiment with? Sorry for all the questions, finding this quite a tricky learning process. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 17601 Registered: May-04 | . Spending approx. $400 on an amp probably isn't your best option. The Rotel you linked to is an integrated amplifier which would mean you're doubling up on features and controls. (The Marantz doesn't want to show up on any search engine but by the model # I would guess it is also an integrated amplifier.) If you have $400 to spend, you would want to add a straight "power amplifier" to the system IF your receiver has "pre amp outputs". Most inexpensive HT receivers won't provide this option. Even with the outputs, inserting a power amp into a HT receiver isn't clear cut. There will be issues of set up and system balance. However, if you can try a power amp, then that's one option available to you. The better option, IMO, is to simply replace the Pioneer completely. Your $400 plus a bit should get you a Harman Kardon receiver capable of driving the load of your speakers. There are other options of course but, if you're interested in gaming and staying with a surround format system, an HK HT receiver would be a good place to start IMO. . . |
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Gold Member Username: MagfanUSA Post Number: 2960 Registered: Oct-07 | First, the sub connected thru the RCA 'sub out' will have NOTHING to do with the problem. It draws no power from the receiver. It may draw enough power from the wall to lower voltage to the system....and have an adverse effect. This is about 1% actually possible. You'd see the house lights dim on the loud passages. The XTZ speakers...depending on model can use some very hi-grade parts. SEAS makes great drivers and if integrated properly with crossover, other drivers and enclosure, potentially make a fine system. However, a SMALL fly in the ointment is that while impedance is important, especially since your receiver is NOT rated below 6 ohms, it that of Phase. If the speaker appears to the amplifier as mainly a capacitor or inductor, the 2 main 'ingredients' of crossovers, the amp will fall flat on its ar$e. Setting your main speakers to 'small' is about all you can do. As an experiment, DISCONNECT the sub. Even unplug it from the wall power. Than set the main speakers to large. This should make the problem worse......Much of the power needs from the amp occur at lower frequencies, which also happens to be where IF there is an impedance dip and a higher than normal phase angle, you'll have problems. Setting to 'large' will just be another confirmation. I looked at the back panel photo. NO amplifier outputs. So, if you really like those speakers, you need a more.....robust.....amplifier. An amp capable of driving such a load. And while the 8ohm rating of 110 watts / channel would ordinarily be encouraging, it is only at 1khz.....and only increases to 125 at 6 ohms. This is ONE chanel driven. Crank up a nice, effects-laden movie with a heavy draw on ALL channels at once and ZAP.....no sound at all! In the world of stereo, the most capable amplifiers are generally considered to 'double up' when impedance drops by 1/2. The 110 watts should go to 220 at 4ohms. I'd expect the Pioneer in question to do no more than 50 or 60 watts at 8 ohms.....with 5 channels driven to 'redline'. Jan's recommendation to simply replace the Pioneer is a sound idea, if you'll excuse a bad pun. I'd ADD that any proposed replacement should have PRE AMPLIFIER outputs so you can 'upgrade' the amplifier as need arises and spare the receiver. They almost ALL run hot, anyway, and moving the hot, amplifier function away can only make the receiver last longer. You could get a stereo amp and use it for the mains. An Emotiva as linked would work wonders......They are a tick over 400$. http://shop.emotiva.com/collections/x-series/products/xpa200 In the receiver line, Sure, HK is fine. Other makers do well, too, however, like perhaps Onkyo. All other things being equal.....seldom are, of course, simply buy the HEAVIEST receiver. That's the one with the biggest transformer and heat sinks. Watch out for all the goofy features you may or may not ever need. Let us know how this whole adventure pans out........ |
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Gold Member Username: MagfanUSA Post Number: 2961 Registered: Oct-07 | One other very minor point. Jan asks about speaker wiring and possible shorts. Good idea. However, I'd add to ask about wire SIZE. If you are cranking it up and using say.....18 ga or smaller (higher number) OR have especially long runs, you may simply be current limiting the amp. If you ARE using small gauge wire, try rewiring the fronts ONLY with at least 16 or perhaps 14, if the runs are say......20 feet or longer per speaker. Try it with the fronts only. IF that helps, rewire the works with some stouter wire. Save the wire for the next go when you buy a more....capable amp...... |
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New member Username: HezekiahPost Number: 6 Registered: Dec-12 | Thanks for your help guys. Do you know which of these would likely run 4 ohm speakers at a high volume?: http://uk.harmankardon.com/harman-kardon-products-uk/brand_harman_kardon/home_au dio/components/audio_video-receivers.html Even the high end 365 model says "Multichannel Power (all channels driven) 110W per channel, two channels driven @ 8 ohm 20Hz - 20kHz" - does that mean I should discount it? Other than the Harman Kardons, does anyone know of any other models I should be looking at? Thanks again. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 17604 Registered: May-04 | . Your link doesn't lead me anywhere, so I can't comment on any particular model. However, HK was one of the companies which, way back in the late 1960's, developed the idea of good sound being accompanied by a capable amplifier. "Capable" in HK world means, among other values, high instaneous current delivery. As we've noted, your speaker's impedance load would indicate a HK receiver should be a good match. We don't have any specific information about the XTC speaker's real world load characteristics - which is fairly common. Most manufacturers do not post enough information to tell you everything you might need to know about their product. At times contacting the manufacturer can lead to more information and a better sense of what equipment might pair well with the speakers. My experience with HK though goes back to the early '70's (I sold HK and I still have one of their 1970's receivers operating 24/7 in a secondary system). I would tell you they are as capable as any amp in their price range when it comes to driving low impedance loads. I would commment a bit here on leo's post. While certain speakers are seen by the amp as either an inductive or a capacitive load, these are fairly uncommon in mass market systems, in the lower price ranges or in what would be a "conventional" speaker system. And while low impedance is what we see in many speakers, low impedance alone does not disqualify a speaker from use with any amplifier. It's that phase angle that counts as this spec is what determines the severity of the impedance drop as far as the amplifier is concerned. For now I'd just be looking at a high quality amp that does not have any switches which are required to safely drive low impedance loads. If a receiver has a switch which must be engaged when driving less than 6 Ohm speaker loads, look elsewhere. I say that and you might actually find that switch on any receiver you can afford. Many manufacturers use such switches as safeguards for their equipment whether their amp is capable of driving low impedance loads or not. From experience I can tell you people do less than brilliant things and the manufacturers get tired of repairing what someone has blown up. Unfortunately, on paper specs alone are not typically a good way to judge equipment unless you can read between the lines. Manufacturers know how to make their gear look good on paper, whether the equipment can deal with the realworld is another matter. I generally do recommend weight as a decent judge for an amplifier. The power supply typically needs to be fairly heavy to deal with high current storage and delivery. There are a few exceptions to that in modern amplifier technology, but that's a decent place to begin making comparisons. As to wattage, again specs are misleading. Amplifiers are never tested in the same way in which they are used. If your requirement is high volume, then you may be making a mistake with your current speakers. For instance, using the same speaker but doubling the wattage output provides a barely noticeable difference in overall volume. Quadrupling the wattage is still not very likely to make most people happy. So from 100 watts to 500 watts, all things equal, those gains in wattage are not going to get most buyers what they expect. What is more important is the power supply of the amp which can provide sustained high volumes and the "electrical sensitivity" of your speakers. By buying an additonal 3dB in the speaker's sensitivity spec compared to your present speakers, you've essentially done the same thing as doubling the wattage of your amplifier. Not loud still but "louder". Buying 6dB more in your speakers will be a very noticeable improvement in clean volume levels for most listeners. Buying ten dB more in your speaker's sensitivity is the same as buying ten times as much wattage with the same amplifier and should be sufficient for all but the most ardent and determined head banger. Pushing any amplifier hard isn't good for the amp so it's certainly wiser to buy a speaker that makes more volume from the same number of watts. If volume is really important to you, you might check out the NAD line of HT receivers. How well they will work with your speakers is unknown since you have said you like higher than average volume levels. Both HK and NAD have customer support systems where you could ask your question regarding volume vs load. No manufacturer will tell you outright their product will certainly do loud volume at low impedance. No more than a Ford rep would tell you a Mustang can run at 180mph all day without problems. Most manufacturers tend to expect the user to have a certain amount of reasonability in how they use a product. High volumes and low impedance are seen by most amplifier manufacturers as abuse. Buying higher sensitivity speakers is one solution to volume restraints. Pushing the amp until it cries "uncle" is not. . |
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Gold Member Username: MagfanUSA Post Number: 2963 Registered: Oct-07 | Jan, I don't mean to 'pick off' here, but virtually ALL speakers are to some extent capacitive or inductive at some frequencies. These same speakers will, at the transition from capacitive to inductive....or reverse....be, for an instant purely resistive. The real question becomes one of compatibility. Some amps doing well with a resistor are less than stellar dealing with reactance in any form. The other part of compatibility, as you noted, is listening habits. The head bangers, as you put it, will destroy even amps on the capable side while toasting the speakers. I'd agree, however, that inexpensive speakers are designed with such reactive excursions kept to a minimum.....the intended user doesn't want or need 1200$+ worth of amp for 500$ worth of speaker. Your thought about reasonability IS reasonable. Intended use rules. My panels will only play so loud, regardless of amp, for example. I knew that going in. Ford recently marketed the '200mph Mustang'. Well, the testers could get it to the 190s. It was a warm (hot, really) day so they called it a 200mph car. The difference between say....195mph and 201mph is well north of 100hp, so I'm not seeing it happening. Maybe straight away in cool damp weather you could coax it to the goal? Pack the intake in ice, while you're at it...an old drag racing trick. Fastest factory Mustang ever? Yes. 200mph+? TBD. Besides HK? Well.....Onkyo or perhaps NAD. You can find fans of virtaully ANY equipment line. Yamaha? Marantz? Pioneer? Denon? All will have followers. I'd suggest a trip to the local retailer for a listen / look. You may get to the point of in-home demo or even draggin a pair of speakers TO the dealer to see how capable the amp in question really is....for YOUR use. |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 17605 Registered: May-04 | . "I don't mean to 'pick off' here, but virtually ALL speakers are to some extent capacitive or inductive at some frequencies." Yes, I know most speakers are not purely resistive loads, leo. We've been down this road together and we both know that. I also know most speakers are not seen by the amp as a "mainly" capacitive or an inductive load only. Or over a broad enough region of their bandwidth to shut down a well built, high quality amp. We both know it is the combined low impedance and high phase angle which makes life difficult for amplifiers. For reasons of legal liability, I can't see anyone at the local Ford dealership suggesting a customer "take 'er out and see if you can hit 200". I'd agree the Onkyo receivers are probably capable of driving the op's speakers to satisfactory volume levels. I've not looked at their products recently. IMO you're still paying for a bit too much gee-gaw ga-ga in features that aren't really needed on a HT receiver with most of the Onkyo line. Not a Sony but still Japanese by attitude. I could be wrong. Like I said, I haven't looked closely at Onkyo in many a year. Plus, I still think the NAD and HK have better sound quality than the last few Onkyo's I've heard. Cambridge might also be a consideration depending on the budget. . |
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New member Username: HezekiahPost Number: 7 Registered: Dec-12 | Cheers guys. Jan, in terms of HK's I've found three AVR's that vary from mid to high-end. I know I will need to test to be totally sure of the performance I can expect, but are you able to offer an opinion as to whether they would be good guys. Hopefully you can see these links!: http://www.amazon.co.uk/Harman-Kardon-AVR-165-230/dp/B0051EAITS/ref=sr_1_1?s=electronics&ie=UTF8&qid=1357256863&sr=1-1 http://www.amazon.co.uk/Harman-Kardon-AVR-265-230/dp/B0051EAIXE/ref=sr_1_4?s=ele ctronics&ie=UTF8&qid=1357256196&sr=1-4 http://www.amazon.co.uk/Harman-Kardon-AVR-365-230/dp/B0051EAJ2E/ref=sr_1_3?s=ele ctronics&ie=UTF8&qid=1357256196&sr=1-3 Sorry for all the questions, just would be great to get some expert advice as I narrow down my search. EDIT: In terms of weight, these three models seem to range from 9, to 11 to 12 kgs. These links to the official site say work if you have the will/desire: http://www.harmankardon.com/estore/hk/us/products/AVR-1650/AVR%201650_HK_US?searchMode=regularProductOnly http://www.harmankardon.com/estore/hk/us/products/AVR-2650/AVR%202650_HK_US?searchMode=regularProductOnly http://www.harmankardon.com/estore/hk/us/products/AVR-3650/AVR%203650_HK_US?searchMode=regularProductOnly |
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Platinum Member Username: Jan_b_vigneDallas, TX Post Number: 17606 Registered: May-04 | . HK is fairly consistent in their sound quality from model to model. The least expensive receiver has so little difference in rated output that you'll never know the difference between it and the two higher rated amps. The top two receivers are both said to have 35 amp current delivery. That would make either of those two my preference for your needs. It's rather diffcult to say you would notice an audible improvement by going with the highest priced receiver. Look at the features offered on each model and don't over buy on gee-gaws. Many of the video and audio enhancements are never going to be used by most buyers. How many surround fields do you need? I need, maybe, two. So it would be a waste for me to buy a HT receiver based on the number of surround fields it has included. All things equal, the more money that has gone into features, the less money is available for quality. If you're budget can stretch to the two higher priced models, select which best suits your actual needs and give that reciever a try. Of course, it's best to actually audition the product before you buy. Many brick and mortar shops will still allow you to bring your own speakers in for the audition if you're courteous enough to schedule some time on a slow weekday morning or afternoon. Lacking that, I'd say contact HK and just ask a few questions about their receiver and your speakers. HK also has their own store - or, at least, they used to have their own store - where you can buy refurbished gear at a slightly reduced price. But if you find a shop that will let you audition the gear, don't screw them over just to save a few bucks. Local dealers need to be supported or else there will be a day when there are no more local dealers. And there is always a benefit to having a local dealer who can provide after the sale service and advice or even some set up assitance. Take your time and don't buy just to buy. Make sure you have the receiver you think is best going to suit your needs for the next half dozen years at least. I've owned my two main power amps for thirty years because I knew they were high quality components built to last and sound good for all these many years. IMO a good deal is when you are still happy with your decision to buy a component many years after the actual purchase. . |