Bottlehead Forum

General Category => General Discussion => Topic started by: aragorn723 on October 23, 2014, 04:39:03 PM

Title: channel imbalance problem
Post by: aragorn723 on October 23, 2014, 04:39:03 PM

Hi,

I have been searching the forum for a solution to the channel imbalance issue on the stock pec pot (I have the Quickie).  There seems to be a strong following for the Alps Blue Velvet stereo rk27, and some think that a stepped attenuator is the only way to go.  A third option is some kind of resistor mod.  Would changing to the Blue Velvet or stepped attenuator make a big difference in sound quality as well as the imbalance?  Thanks,

Dave 

Title: Re: channel imbalance problem
Post by: Paul Birkeland on October 23, 2014, 05:11:32 PM

Is there strong channel imbalance at all levels, or just in the first 1/8 of a turn or so?

Title: Re: channel imbalance problem
Post by: aragorn723 on October 24, 2014, 01:40:35 PM

Paul,

just the first 1/8 or so.  If the volume is on 0, then is gradually raised, one channel plays, and then you have to turn a bit more to get the other one to turn on.  Most of my listening is relatively volume; so the goal is to be able to have control in that volume range and have both channels play.

Dave

Title: Re: channel imbalance problem
Post by: Paul Birkeland on October 24, 2014, 02:52:55 PM

The resistor mod will work for you. Try 75k resistors from the selector to the pot and 33K resistors between each pair of outside lugs on each level of the pot.

Title: Re: channel imbalance problem
Post by: aragorn723 on October 24, 2014, 03:18:07 PM

Paul,

Right now there are 100K resistors going from the left and right output of the selector switch to the inputs of the pot to attenuate the input signal.  Does anything for the channel imbalance mod change since these are in place?  Thanks,

Dave

Title: Re: channel imbalance problem
Post by: Paul Birkeland on October 25, 2014, 02:09:14 PM

Yes, replace the 100K resistors with 75K resistors, add the 33K resistors.

What speaker/amp combo do you have?

Title: Re: channel imbalance problem
Post by: aragorn723 on October 25, 2014, 04:31:20 PM

Paul,

The amp is an Inter-m R500, and the speakers are Definitive Technology BP6Bs.  Thanks,

Dave