posted
Well, after an hour on the phone with tech reps at Xtant, I had the tech reps completely baffled as to what has been causing the noise in my car. So, they sent my call over to engineering, and I talked to the guys that actually designed the Xtant amps. Anyway, I have a condition in my system known as "heterodyne". What it is is that the power supplies on these amps are supposed to be 33 khz. However, due to the slight variance that is inherent in electronic components, one of the power supplies is just different enough to cause what is called a "beat frequency". This beat is what I have been hearing and the only way to get rid of it is to change one or both of the amps. I have no warranty, so I am feeling totally screwed. I have Xtant, OZ subs, and Focal Utopia's and they are totally useles due to this one unlucky break. Damn, this sucks!
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Posts: 232 | From: Coeur d' Alene, ID | Registered: Jul 2000
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posted
That bites. Over the years a couple of different companies have offered 'master and slave' connections on their amps so that the 'master' controls the switching speed of all the rest. I thought it was a bunk feature up until now....
------------------ Blow your mind - PORT your box!
posted
Did the tech say the noise was being transferred through the power wires or rca cables...... It seems to me you could seperate the two amps from power with an isolator (you would lose .7v, but if it worked.....) or if it was over the rca cables you could isolate it with some type of preamp, maybe an eq, that has very high isolation between its outputs...There has to be a way around this???? Audiophyle??? Maybe this is one for Wayne????
PS Did the techs at Xtant remember the problem with ringing torroids???(having to press on them to get them to stop)... They are the ones that told me how to fix it, but that was on 3300s and 3150s mainly...
posted
It isn't the torroid. I tried it. It is definitely a beat frequency. I am hoping that moving them farther apart will solve it. The EMI of one amp is corrupting the other, so it doesn't even need RCA's to do it.
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Posts: 232 | From: Coeur d' Alene, ID | Registered: Jul 2000
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quote:Originally posted by 300ZXNA: It isn't the torroid. I tried it. It is definitely a beat frequency. I am hoping that moving them farther apart will solve it. The EMI of one amp is corrupting the other, so it doesn't even need RCA's to do it.
Oh, I wasn't trying to say it was the torroid, just asking if they remembered having that problem??
posted
Well, they did say that sending them in may be the only way. Problem is that I bought both amps used, thus no warranty. Also, the way the engineer explained it to me, matching them exactly would be no small feat, considering the problem could be from all sorts of components. Replacing one if not both of the amps is the only way to fix it.
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Posts: 232 | From: Coeur d' Alene, ID | Registered: Jul 2000
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------------------ HU- Pioneer Premier PEH-P720 80hz & up- Pioneer Premier 6x9's Sub Amplification- Kenwood KAC-428S amplifier 80hz & down- Memphis PowerBass 15" sub in a ported 3.0 cubic ft enclosure
Quit telling people what your "going to do" and do it.
WILLING TO PAY $$$ TO ANYONE WHO HAS VIDEO OF THORS' SMOKING POWERBASS INCIDENT
posted
Screw warranty - there is nothing that could have been done to the amp(s) to cause them to be like that. They left the factory that way.... Manufacturing flaw - they should be happy to get them back in to search out the cause...
------------------ Blow your mind - PORT your box!
posted
still working on it. Through talking to the engineers, I was able to get the noise to stop, only it induced massive alternator whine! AAAAAAAAAAAAAAAAAAAAARRRRRRRRRRRRGGGGGGGGGHHHHH!!!! If it is not one thing, it is the other.
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Posts: 232 | From: Coeur d' Alene, ID | Registered: Jul 2000
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posted
I've been on vacation... Have you tried grounding the RCA cables at the amplifiers?
Have you tried grounding the heatsink of the amplifiers? I've seen instances where that works, although generally it's NOT the way you want to do things.
Have you tried physically separating them in the car? Hey, here's an idea.... go get 2 caps of equal value. I'm talking like 1/2 farad each, then wire them up and ground them in different places. I've seen switching noise go away using these, in fact, my first Nak amp had noise till I used a cap.
I'm in agreement with Dukk, I think I'd be happy to get them in if I were the engineer at xtant!!!
------------------ Ron Hawkins
Sometimes the majority only means that all the fools are on the same side.
Use your ears to judge components, NOT your wallet! K.I.S.S.
posted
I have tried all that you suggest. The double edged sword is that when I can get rid of the heterodyne EMI, the alternator whine finds a way into the signal. When I get rid of the whine, I get the heterodyne. Anyway, I am getting very frustrated. Replacing one or both amps may be the only way.
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Posts: 232 | From: Coeur d' Alene, ID | Registered: Jul 2000
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posted
Try a different amplifier before you go buy one. See if a local shop will let you borrow one and figure out exactly which amp is making the noise....
------------------ Ron Hawkins
Sometimes the majority only means that all the fools are on the same side.
Use your ears to judge components, NOT your wallet! K.I.S.S.
posted
well, after talking to the engineers at Xtant, they know without a doubt that it is heterodyne noise. The bad news is that it is a bitch to get out. So at least I know what the problem is (the clocking of the power supplies are slightly out of sync causing a beat frequency). I might be getting a job at a stereo shop soon, and then I would have all sorts of goodies to play with and find out what is giving me such a hard time.
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Posts: 232 | From: Coeur d' Alene, ID | Registered: Jul 2000
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