[briano]

I just purchased a supreme, and it has a little strangeness in the right hand channel that has me wondering if it is a unit defect.

What I first noticed is that in quiet passages I am getting a static sound ONLY in the right hand channel whenever I cross the halfway point with the volume knob. It only happens while the knob is moving, and is also accompanied by a little jump in the gain.

I sent it back to headroom and they replaced the volume pot, but I got it back and it still does exactly the same thing. The left channel is beautiful, but the right has this annoying muffled static.

To avoid having it be related to my equipment, I powered off the amp and disconnected the source cables. Then, when I switched on the amp with the gain switch set on high, the left channel did exactly what I expected: very quiet 60Hz hum that gets louder as you turn the volume all the way up. The right channel would have the same hum up to the halfway point, then static intrudes (even when the knob is stationary) and the static gets louder and louder until about the 3/4 point at which time the right channel goes silent (no hum either).

Has anyone else noticed that the two channels \behave so differently like this?
The amp is back at headroom, but I don't want to waste their time (and mine) chasing something that is just a design feature...

To be fair, if I leave the volume knob below halfway, this amp is the best thing I have ever heard!

Any help appreciated.
btw, I listen with ER4S and HD580s.....

 

[fredpb]

I would say if I had your Supreme it will stay at Headroom until it was fixed. If you can reproduce the problem constantly, tell them about it. They should be able to reproduce it too. If you get it back defective, start screaming.

 

[FCJ]

I noticed a similar problem with a Cosmic. After calling and finding out it was normal, I returned the unit for a refund. It didn't interfere when music was playing, but it bothered me nonetheless.

 

[briano]

Today I got the answer to my own question, it was NOT normal. They sent me a new one and it is much better. There is still very slight noise on the upper half of the volume, but I found an explanation on this web site mentioning that they made a design trade off where they do not put damping capacitors in the circuit path to stop the volume change noise. They assume you won't change it a lot while you are listening. It is MUCH more subtle now and the same in both channels. The funny noise in the right channel is not present. Overall great sound!

 

[FCJ]

Quote:

Originally posted by briano Today I got the answer to my own question, it was NOT normal. They sent me a new one and it is much better. There is still very slight noise on the upper half of the volume, but I found an explanation on this web site mentioning that they made a design trade off where they do not put damping capacitors in the circuit path to stop the volume change noise. They assume you won't change it a lot while you are listening. It is MUCH more subtle now and the same in both channels. The funny noise in the right channel is not present. Overall great sound!

That explains the problem I was having. Which, I guess, wasn't a problem at all, but it did bother me enough to return the amp. Glad you got a replacement. Headroom's service is top notch.