Noisy power with DAC-ah question
Mar 1, 2006 at 10:02 PM Thread Starter Post #1 of 5

randyruiz

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Ok I just got my DAC-ah and the noise floor is high and it just sounds like crap because of it. Compared to the DAC-ah my revo 7.1 is absolutely black in between the notes. (My PC has an expensive aftermarket regulated power supply) So my question is if I were to plug my DAC-ah with its crapy power transformer into a good line conditioner would this be as good as upgrading the DAC-ah's transformers?
 
Mar 1, 2006 at 10:03 PM Post #2 of 5

Jahn

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whoa - i have zero problem with the noise floor on my DAC-ah. on the other hand, one of the first things lan did with it was improve the power stage (somehow, i dunno how, hehe). i usually run mine from a monsterpower pc1000, so something like that couldn't hurt.
 
Mar 1, 2006 at 11:26 PM Post #3 of 5

Firam

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Try this straight out of the Pacific Valve DAC-AH manual:

Sound is hissy and there is considerable hiss:

You may have connected and reconnected the digital cable and low jitter clock is unable to sink.

1. Turn the DAC-AH off
2. Disconnect all the digital cables
3. Turn off the digital source
4. Wait 5 minutes
5. Plug the digital cables back in
6. Turn unit on

Edit: I should have put down the whole thing. Don't bite my head off I'm only trying to help. How do you know it is the power stage? I have no hiss what-so-ever unmodded.
 
Mar 1, 2006 at 11:34 PM Post #4 of 5

randyruiz

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Quote:

Originally Posted by Firam
Try this straight out of the Pacific Valve DAC-AH manual:

1. Turn the DAC-AH off
2. Disconnect all the digital cables
3. Turn off the digital source
4. Wait 5 minutes
5. Plug the digital cables back in
6. Turn unit on



Your kidding right? The noise I hear is very much a AC hum. How would a DAC "cold reboot" fix this? I think improving the power stage is the way to go. The question is what would this involve? Replacing the transformer for two new ones that are linear/regulated in nature? replacing output caps? changing resistors? This almost sounds like a question for the DIY section. Thoughts?
 
Mar 2, 2006 at 12:22 AM Post #5 of 5

Samgotit

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I just posted a thread about the ps on the DAC-AH in DIY.
http://www6.head-fi.org/forums/showthread.php?t=166545

Mine has virtually no noise unless my amp is turned all the way up. I then hear something that could be AC, but I can't be sure. My amp alone has no noise floor. I suspect a ps upgrage could be good for the DAC-AH.

I can hear the caps discharge when I turn it off with the amp on.

My caps and resistors are stock, except the coupling caps, they are Black Gate.

Sam
 

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