strangelove
100+ Head-Fier
- Joined
- Feb 9, 2002
- Posts
- 364
- Likes
- 10
Hello all. I just bought a used Woo Audio 4 Upgraded amp from a fellow headfier. It's a very lovely sounding amp, I really like it a lot. However I noticed a low level static hum that seems to be getting louder. To describe it:
there is a low level static hum in both the Lt and Rt channels that is noticible when there is no sound playing (even when no source is attached) or very soft passages. It's not loud enough you can hear it when music is playing. There's a high/low impedance switch and it occurs with either selected. There is also a louder intermittent fluttering static noise that only occurs in one channel. I tried switching all the tubes from left to right (there's two each of three different tube types). I narrowed it down to the static sound flips from Lt to Rt when I switch the location of the largest of the tubes (not sure which number it is). This makes me think that part of the problem may be from a bad tube. The rest I'm not sure of.
I emailed Woo Audio but didn't get much help. Jack said the amp should be dead silent at rest and thought it could either be bad tubes or something with the amp. The previous owner claims it worked upon shipping so maybe something happened in transit. Another problem is the previous owner sold it to me claiming there were two sets of tubes included (which now he says he was mistaken about). In fact there was only one set of the 6C19 and EZ80 and two pairs of ECC82 and one pair of ECC88 (which I don't know which one they are a replacment for).
So I'm kind of at a loss where to proceed from here. Looking on Ebay replacement tubes are probably going to cost around $50-60 bucks which stinks because I bought it believing it was going to come with the extra set of tubes I'd need if anything went wrong. Then if I get new tubes and still have the problem I'll have to send it off to get fixed which I'm sure won't be cheap because the shipping alone will be $40-50 each way.
Anyone have any ideas what the problem may be and where to go from here?
Also, can using the amp in this condition make the problem worse? I'd imagine so, so I've stopped listening to it as the noise seems to be getting louder.
there is a low level static hum in both the Lt and Rt channels that is noticible when there is no sound playing (even when no source is attached) or very soft passages. It's not loud enough you can hear it when music is playing. There's a high/low impedance switch and it occurs with either selected. There is also a louder intermittent fluttering static noise that only occurs in one channel. I tried switching all the tubes from left to right (there's two each of three different tube types). I narrowed it down to the static sound flips from Lt to Rt when I switch the location of the largest of the tubes (not sure which number it is). This makes me think that part of the problem may be from a bad tube. The rest I'm not sure of.
I emailed Woo Audio but didn't get much help. Jack said the amp should be dead silent at rest and thought it could either be bad tubes or something with the amp. The previous owner claims it worked upon shipping so maybe something happened in transit. Another problem is the previous owner sold it to me claiming there were two sets of tubes included (which now he says he was mistaken about). In fact there was only one set of the 6C19 and EZ80 and two pairs of ECC82 and one pair of ECC88 (which I don't know which one they are a replacment for).
So I'm kind of at a loss where to proceed from here. Looking on Ebay replacement tubes are probably going to cost around $50-60 bucks which stinks because I bought it believing it was going to come with the extra set of tubes I'd need if anything went wrong. Then if I get new tubes and still have the problem I'll have to send it off to get fixed which I'm sure won't be cheap because the shipping alone will be $40-50 each way.
Anyone have any ideas what the problem may be and where to go from here?
Also, can using the amp in this condition make the problem worse? I'd imagine so, so I've stopped listening to it as the noise seems to be getting louder.