New crack - right channel slightly quiet Voltage different but in range

ryanppax · 486

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Offline ryanppax

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Hi all,
First up is the audio symptom. At the very lowest audio level you can here more sound from left channel. And switch the amp off during playback, youll hear the right channel fade first before the left. At higher volumes it sounds great, and honestly just being nitpicky

Finished up my crack yesterday. Went thru all the resistance checks and they passed.
Started testing voltage, and found no/low voltage on terminal 5. and 1 LED failed.

Upon further review I found I soldered 1 wire/resistor to 5U and the 5U >  tube wire wasn't soldered.
I soldered that in, and did my voltage checks again.

Measuring voltage on the channels again. My Right channel is reading a steady 90v T5 and 90vT9.
The left channel was slightly higher (cant remember exact value). Terminals 2 and 4 were reading equal.

The only thing I notice could be wrong would be the resistor body is touching T4 if that matters. Googling says not likely.



Offline ryanppax

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:facepalm:  I guess I should have read the  sticky first.
Seems like my issue... But will I increase the noise level by doing this?
Im using 300ohm HD660s2

3.  I can barely turn my Crack up at all before it's far too loud, what do I do?

Disconnect the white wire at the pot that originated at the left RCA jack.  Install a 75K resistor between this wire and where it connected on the pot.
Repeat this step for the red wire coming from the right RCA jack.
Attach and solder one 33K resistor between each outer pair of lugs on each level of the volume pot and the ground lugs on the pot.
Resistor wattage is unimportant, 1/10 Watt or greater will work nicely.

See the photo at the end of this post for how these resistors are attached to the pot.

4.  I have some channel imbalance in my volume control at lower levels, what should I do?

The solution to #3 will also solve this issue.



Offline Paul Birkeland

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Yes, I would try adding the resistors to the volume pot first. 

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man