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Hello,
I've got a legato directly coupled to my AMP using the volumite as a volume control.
On the right channel I get a lot of clicks and pop noise, I can barely hear it from my listening position, but it is a lot louder than the left channel, which is almost totally quiet.
I've replaced all of the active components in that channel, even replaced some caps, but it almost seems if the pop noise is burried inside the pcb. I can't get rid of it.
What to replace next?
Emile
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Are you certain where the issue lies?
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Hello Russ, Pretty sure the problem lies in the right channel of the legato. I have switched the internal wiring (output SE) left and right, the problem switched from the right channel to the left channel. I've tried the balanced output, same problem. (even using only the pos or neg side of the balanced output) Also have inserted the buffalo so that the left buff connected to the right legato channel. Switched back to the ivy i/v stage, dead quiet, no noise at all. It's just a tiny signal, on my scope (5mv/div) I can barely see it, about 0,5mv to 1mv of distortion noise, with little peaks/spikes. Tried to make a video recording of it, but you can hardly see it, I could try to make a recording of it using my soundcard if that would help. Emile Edited by user Wednesday, September 29, 2010 2:58:41 PM(UTC)
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A very interesting situation you have there emile.
If i had to guess i'd say a dodgy electrolytic cap might be causing your grief. Was C16 one of the ones you swapped out? Or even C6,C7, you could probably take the output before those, and use some other caps, just to see if they're the issue without having to desolder them.
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Dingo,
I've replaced C3, C4, C21 and C22, even replaced C16.
I'll try to measure or bypass c6 and c7, and if that helps. (and try to make a recording of the legato using a soundcard...)
Emile
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I've made a recording of it. The left channel has just a tiny bit more noise than de base noise from the ADC. The right channel has all sorts of spikes and noise. The recording was amplified (digitally) about 50db. Emile http://www.mediafire.com/?bxyjn7vegrngm9jEdited by user Wednesday, September 29, 2010 2:58:19 PM(UTC)
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Are you using the output buffer? If so try omitting it.
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No I'm not using the buffer Russ, are the legato's that you have quiet on both channels, or haven't you tested it so far down? (btw you can barely measure it on a normal scope)
I do think most of the legato's are used with a preamp, then you would probably only notice it when the volume knob is >2/3 I think.
Emile
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Clicks could be a resistor related problem, are any of the R's (very) hot?
Have you got sufficient cooling in general?
I can recommend electronic cooling spray, that's often a wonder tool in chasing failures.
Cool one component at the time while playing/measuring, this could reveal the faulty part/joint.
Good luck.
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Mine are completely silent. I always run directly into a power amp. Both channels are the same in any case so its a bit odd it's only happening on one channel for you. Edited by user Thursday, September 30, 2010 3:02:05 PM(UTC)
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Guess what, mine has evolved the same behaviour. The one channel is silent, the other clicks and pops. It's faint, but it's there. It sound as Steamerzone has recorded. I'm running it directly into a LM3886 without the buffer. It can't be heat related it pops right after cold start. The faulty channel plays distorted when playing silent. Edited by user Thursday, October 7, 2010 11:11:58 PM(UTC)
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What voltage do you have your bias set at?
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Hello avr300, welcome to the party. :-)
I've spend a lot of evenings trying to pinpoint the problem to some component or whatever...last week I took a week off, and just enjoyed the music coming from it.
Only at night when it's very quiet outside I can hear it from my listening position. (pretty powerfull amp)
Sad for you, but alas I don't feel so alone anymore...
Emile
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This could be your I/V stage picking up some EMI. Check carefully your wiring routes.
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I'm running it at +-13V. Quote:"This could be your I/V stage picking up some EMI. Check carefully your wiring routes" BII and Legato ?? Not much wire involved, is there ? And why only the left channel ? I might add, I have been testing without the BII attached (not even powered), because I remember having a similar problem with the BI when used stacked on top of the IVY. The sound is somewhat similar to then, only then the problem was the BI radiating into the IVY. It was cured by increasing the distance between the two. But thats not the cause now. The Legato runs open wire at input upon test. This is a puzzle. Could it be power supply related - not really, since I only have the problem in one channel. Steamerzone - have you tried it without the relay ?? Edited by user Friday, October 8, 2010 1:18:56 PM(UTC)
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No not without the relay yet...but I did remove R11 and R12 at one time, just to be shure it wasn't pop noise from the opamp. Also removed R3 and R4 (one at a time) but no dice, couldn't rule out the + or - side....seems to be something in 'common' of the + and - side. Emile Edited by user Friday, October 8, 2010 1:28:45 PM(UTC)
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I replaced the opamp yesterday (a bitch to unsolder) - no difference. Who do the relay ? edit - newer mind the relay, the problem also exists at the balanced pins, long before the relay. Edited by user Friday, October 8, 2010 1:31:39 PM(UTC)
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avr300,
Is it also the right channel for you that has the noise?
Emile
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Nope. Left.
The strange thing though is, it has been working perfectly.
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I think mine has done it from the beginning. But I'm not sure about that. One day I just noticed some very strange noises from the right speaker, which first led me to investigate the amp that I recently modified. But it turned out to be the legeato, especially when warming up, it sometimes can get pretty loud, and then evens out a bit. quote of the day? The CFPs are high gain and can be finicky. Edited by user Friday, October 8, 2010 1:57:13 PM(UTC)
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