millett problem
Feb 25, 2006 at 3:37 AM Thread Starter Post #1 of 16

dhp

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the sound that comes out is only through the left channel. There is no sound coming from the right side, but sound that should be coming only from the right side is smushed all into the left side. Any possible solutions for this problem with my millett? There are no solder bridges (hard to do on this board!).
 
Feb 25, 2006 at 6:01 AM Post #2 of 16

pipp

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Try turning the right channels buffer around
wink.gif
 
Feb 25, 2006 at 6:28 AM Post #3 of 16

dhp

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hmm... switching it around didn't do anything... im using the OPA551, could it be possible that it's the way im shorting out pins 2 and 6?

rawr.jpg


is it shorting out the same way no matter how it's oriented? whether upside down or right side up?
 
Feb 25, 2006 at 6:45 AM Post #4 of 16

pipp

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I where using the buf634 when I fist buildt it and had the exact same problem as you, turned the buffer and everything worked fine. Im not familier with the opa though. The right and left buffer should be different ways. If you have them the same way now, turning the right one, you have to reconnect pin 2 and 6 as they change when you turn the buffer. You might have tried this already just a thought if you havent.

I assume you have adjusted the bias of both rails ?
Checked that all resistors are correct/soldered properly ?

If you have tried all, im out of ideas right now...
 
Feb 25, 2006 at 7:09 AM Post #5 of 16

dhp

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well, there is sound from the right side, it just appears only in the left side. right side sound is mashed into oblivion, then dropped into the left side. Dunno if you're familiar with the song Astronomy Domine by Pink Floyd, but it starts off with beeps in the right side only. When I play it through my amp, its very distant sounding in the left side only. In that case, i don't think the bias would matter, beause if right side bias was really low, then it'd sound distant in the right side, not the left
 
Feb 25, 2006 at 9:33 AM Post #6 of 16

dhp

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after over a freaking hour of desoldering, i desoldered 2 alps 50k rk27 pots and put a different pot into my millett, and still no luck. so the pot isnt the problem... i think
 
Feb 25, 2006 at 11:07 PM Post #7 of 16

gsteinb88

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Were i you i would take your multimeter, and start checking resistances across different parts of the circuit, until you find one that doesnt match up like it should.
Basically, there is a short somewhere, in all likelihood, and probably at a point where the right channel hasnt been amped yet, or is running through some extra resistance. Check if it is shorted to the ground.
-g
 
Feb 25, 2006 at 11:25 PM Post #9 of 16

n_maher

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Please double check the value of your output resistors and report back, is the left channel (the one getting amplified) really getting amped or is it just producing sound. It sort of sounds like you might have the old 22k output resistor instead of a 22ohm resistor.

Also try swapping tubes from left to right to see if the problem follows the tubes.

And be sure to check the wiring of your inputs and outputs.

Nate
 
Feb 26, 2006 at 5:06 AM Post #10 of 16

dhp

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hmm... R5R is giving me 454 ohms... not 1000 ohms... even though the marking on it clearly states 1001F. that's really fruity


but it didnt solve the problem


hmm, the resistor measured at 1k ohms, but while soldered into the circuit, it measures at 460 ohms...
 
Feb 26, 2006 at 4:33 PM Post #11 of 16

n_maher

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Quote:

Originally Posted by DieInAFire
hmm... R5R is giving me 454 ohms... not 1000 ohms... even though the marking on it clearly states 1001F. that's really fruity


but it didnt solve the problem


hmm, the resistor measured at 1k ohms, but while soldered into the circuit, it measures at 460 ohms...



Did you check R4L/R?

Nate
 
Feb 26, 2006 at 9:28 PM Post #12 of 16

gsteinb88

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Quote:

Originally Posted by DieInAFire
hmm... R5R is giving me 454 ohms... not 1000 ohms... even though the marking on it clearly states 1001F. that's really fruity


but it didnt solve the problem


hmm, the resistor measured at 1k ohms, but while soldered into the circuit, it measures at 460 ohms...



That is because there is a 454 ohm way to get from one side of that resistor to the other. Your short is situated in that part of the circut. I dont know the millet setup, but it sounds like that resistor is shorted to another that connects to a common rail on both sides. Thus, the short exists there.
-g
 
Feb 26, 2006 at 9:59 PM Post #14 of 16

diredesire

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Doubt this will solve your problem, but I accidentally mis-soldered my 1/4" jack due to it being my first time working with it. I accidentally soldered the ground to the right side of my amp, and had a similar response to yours, i had a "mono" type sound in the left ear, and a "cross-feedy" sound in my right.
 
Feb 26, 2006 at 10:09 PM Post #15 of 16

n_maher

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Quote:

Originally Posted by DieInAFire
hmm, the resistor measured at 1k ohms, but while soldered into the circuit, it measures at 460 ohms...


I just checked a working Millett for you, that resistor should measure at 1K even in the circuit so something is definitely wrong there. I think it's high time to post a picture (clear, detailed) of the top and bottom of the board. If you can get the board on a flatbed scanner and scan it at a decent resolution.

Time to start hunting for the short.

Nate
 

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