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Laney VC 50 Issues

9/27/2003 1:31 AM
Brad	Laney VC 50 Issues I have a few questions I'm hoping you can answer in relation to the above model amp. 1) I've added a 1 ohm resistor to the cathode circuits for the output tubes to assist in setting the bias of the amp and the default setting was for 11mV(11mA) per tube. This would seem to be a bit on the cold side to me - I would have expected to see 20 - 30mV for 5881's. What would be the preferred idle current per tube for this amp? 2)The reverb appears to be very weak on the amp on both channels. I've tried a known good reverb pan and it was the same. Are there any known problems with the reverb? 3)I've noticed that there appears to be times when the amp will switch channels randomly (not often) - is there any known modification to prevent this from occurring? I have a schematic for this amp - let me know if anyone else needs a copy. regards, Brad

9/27/2003 1:31 AM

Brad

Laney VC 50 Issues

I have a few questions I'm hoping you can answer in relation to the above model amp.

1) I've added a 1 ohm resistor to the cathode circuits for the output tubes to assist in setting the bias of the amp and the default setting was for 11mV(11mA) per tube. This would seem to be a bit on the cold side to me - I would have expected to see 20 - 30mV for 5881's. What would be the preferred idle current per tube for this amp?

2)The reverb appears to be very weak on the amp on both channels. I've tried a known good reverb pan and it was the same. Are there any known problems with the reverb?

3)I've noticed that there appears to be times when the amp will switch channels randomly (not often) - is there any known modification to prevent this from occurring?

I have a schematic for this amp - let me know if anyone else needs a copy.

regards, Brad