JasonJCarney Posted August 12, 2011 Share Posted August 12, 2011 I was over at Brunts house today. I heard the sound. It's not natural! Actually scared me. High pitched screech is a better way to describe it then popping sound. It was horrible. I told him to call the manufactorer as well. That will damage the speakers if not fixed. I also advised him to get an XPA-3 or 5! Lol Quote Link to comment Share on other sites More sharing options...
Brunt Posted August 12, 2011 Author Share Posted August 12, 2011 If you get no cracking unbridged...... You either need to run them as 50wpc single; or yeah.... different amps. (Or accept the possibility of damaging speakers). I seriously would contact the manufacturer........ OK...Just got off the phone with Audiosource. They told me to try unhooking RCA's from amps and then powering them on to see if I get noise. While that might be the only thing I haven't tried, he claims it will show whether or not the issue is my preamp signal or the amps themselves. Now, I HAVE tried powering them up with the AVR off and even unplugged, so I don't think it will matter. Here's where it gets interesting... The gentleman told me that this particular amp does NOT have relays in place to prevent any signal noise or backlash from whatever is causing the interference/noise to happen when powering up or down, just some sort of silicon thingy. From what he said, it sounds as if he is backing up my suspicion of lower end electronics being the culprit...thoughts? Quote Link to comment Share on other sites More sharing options...
Ironsave Posted August 12, 2011 Share Posted August 12, 2011 Brunt, I suspect you have found the culprit.... Quote Link to comment Share on other sites More sharing options...
Beechnut Posted August 12, 2011 Share Posted August 12, 2011 That's a great idea. Makes me wonder if there is any signal faulting to ground to cause it. Can you get a refund if that doesn't work? Quote Link to comment Share on other sites More sharing options...
Brunt Posted August 12, 2011 Author Share Posted August 12, 2011 That's a great idea. Makes me wonder if there is any signal faulting to ground to cause it. Can you get a refund if that doesn't work? Well, I will call again on Monday. I hope they offer some sort of refund. It sucks in a way because they seem well built and they sure make my frontstage sound impressive, but I guess at this point it might be time to try to recoup some cash and grab a better quality amp like an Emo or something. Quote Link to comment Share on other sites More sharing options...
MikeFord Posted August 12, 2011 Share Posted August 12, 2011 The gentleman told me that this particular amp does NOT have relays in place to prevent any signal noise or backlash from whatever is causing the interference/noise to happen when powering up or down, just some sort of silicon thingy. From what he said, it sounds as if he is backing up my suspicion of lower end electronics being the culprit...thoughts? I can only think of a handfull of older amps that disconnected the outputs while powering up, nothing modern comes to mind. Something like 30 years ago most amps made the transition between AC or capacitor coupled designs and DC coupled, and for a few years some of those needed the outputs disconnected until they stabilized. Some Crown amps were like that I think. Turn on pop is often a ground reference issue, how are they bridged? Are they designed to be bridged? Quote Link to comment Share on other sites More sharing options...
JasonJCarney Posted August 12, 2011 Share Posted August 12, 2011 Mike, this is not what anyone would consider a pop noise. It's a high pitched screech that feels like it's gonna rip your eardrum apart... And that was before he powered up the onkyo! Quote Link to comment Share on other sites More sharing options...
Brunt Posted August 12, 2011 Author Share Posted August 12, 2011 The gentleman told me that this particular amp does NOT have relays in place to prevent any signal noise or backlash from whatever is causing the interference/noise to happen when powering up or down, just some sort of silicon thingy. From what he said, it sounds as if he is backing up my suspicion of lower end electronics being the culprit...thoughts? I can only think of a handfull of older amps that disconnected the outputs while powering up, nothing modern comes to mind. Something like 30 years ago most amps made the transition between AC or capacitor coupled designs and DC coupled, and for a few years some of those needed the outputs disconnected until they stabilized. Some Crown amps were like that I think. Turn on pop is often a ground reference issue, how are they bridged? Are they designed to be bridged? Yes they are designed to be bridged and have a switch designating such a function. I've read somewhere one way to avoid ground loop issues is to make sure every single av component is plugged into same outlet(I have a power conditioner). This true? How could I fix it if it was a grounding issue? Quote Link to comment Share on other sites More sharing options...
Brunt Posted August 12, 2011 Author Share Posted August 12, 2011 Mike, this is not what anyone would consider a pop noise. It's a high pitched screech that feels like it's gonna rip your eardrum apart... And that was before he powered up the onkyo!Correct! Quote Link to comment Share on other sites More sharing options...
Brunt Posted August 13, 2011 Author Share Posted August 13, 2011 plugged everything into power conditioner and plugged that into a different outlet...same problem. Must be amp electronics I guess... Quote Link to comment Share on other sites More sharing options...
MikeFord Posted August 14, 2011 Share Posted August 14, 2011 Try what the customer support guy suggested, disconnect everything from the amp inputs and cycle the power. If they make noise something is wrong in the amp, if they don't, more likely a problem in one of the other items. Add them back one at a time until the noise shows up (if it wasn't just an amp issue), then disconnect everything except the offending item to see if its that item or an interaction between it and some other one. Quote Link to comment Share on other sites More sharing options...
Brunt Posted August 14, 2011 Author Share Posted August 14, 2011 Disconnected rca's...and got same results. Its an amp issue for sure. Time for a good 3 or 5 channel amp I guess...sh*t. Quote Link to comment Share on other sites More sharing options...
Beechnut Posted August 14, 2011 Share Posted August 14, 2011 So frustraighting [] Look forward to hearing about the new amp that you get. Quote Link to comment Share on other sites More sharing options...
Brunt Posted August 15, 2011 Author Share Posted August 15, 2011 Oddly, I hooked one Audiosource amp up to my Klipsch speakers in my business in stereo mode and the sounded good and had no sound whatsoever when powering up or down...VERY strange. Quote Link to comment Share on other sites More sharing options...
cornfedksboy Posted August 16, 2011 Share Posted August 16, 2011 Did you ever try them at home unbridged? Quote Link to comment Share on other sites More sharing options...
Brunt Posted August 16, 2011 Author Share Posted August 16, 2011 Did you ever try them at home unbridged? They were unbridged when I moved them to a different setup. I never tried them unbridged on my front stage because I figured it didn't matter, I needed the bridged power. Quote Link to comment Share on other sites More sharing options...
MikeFord Posted August 16, 2011 Share Posted August 16, 2011 Disconnected rca's...and got same results. Its an amp issue for sure. Time for a good 3 or 5 channel amp I guess...sh*t. No Warranty? Bridging usually changes the impedance the amp likes, something that drives 4 ohms in each stereo channel needs 8 ohms when bridged. Maybe that is a factor? I need a reciever myself and plan to hit the two low end stores in town tomorrow, Goodwill and SA, so I can do some testing in my garage. Quote Link to comment Share on other sites More sharing options...
pite Posted August 17, 2011 Share Posted August 17, 2011 Yeah...Try them unbridged. Not going to harm, unless you know for sure that you need that 'bridged power'... Quote Link to comment Share on other sites More sharing options...
JasonJCarney Posted August 17, 2011 Share Posted August 17, 2011 Just for clarification..... the OP tried them "un"bridged and the noise went away. He needs 150watts for his front stage per speaker so he has no use for them in the unbridged state. Looks like it's time for and XPA... Quote Link to comment Share on other sites More sharing options...
T.H.E. Droid Posted August 18, 2011 Share Posted August 18, 2011 I didn't notice that anyone had asked the question about the operating class of these ampliers. A high pitched screeching sound implies some kind of oscillation which is heard only when in bridged mode. Is it possible that the amp stages are Class D or Class T units that produce audio frequencies as they power up and before their circuits stabilize? Because bridging increases the total available gain, this may be something you only hear when bridged. There might also be a bit of interaction between the speakers and amp that might change if speakers of different impedences where used. A lot of the modern electronic devices use these digital amps because they can produce large outputs with only moderate distortion and without large, heavy components. However, it's a good design practice to decouple the speakers when powering up or down (or switching modes) because these amps can produce some severe noise when unstable. My Pioneer A/V receivers have this feature, and you can hear the relay that protects the speakers clicking on and off. I suspect that Audiosource left out this protection mechanism to help keep the cost low on their amps. My Adcom 5500 power amp also lacks this feature, even though it was their most costly 2-channel amp when it was produced. I'm sure the also didn't add relay protection to help keep the cost down. I have an Adcom speaker selector switch that I can disengage when turning the system on and off to keep transients from reaching any of the speakers. Cheap and effective, you might try simply adding a 3 pole, single thow switch into your speaker connects to disconnect the speakers when powering up or down. You can also buy time-delay relays that will do the same job automatically. Quote Link to comment Share on other sites More sharing options...
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