Bottlehead Forum

Bottlehead Kits => Stereomour II => Topic started by: crgolfer on April 14, 2018, 01:57:56 AM

Title: Single input power amp
Post by: crgolfer on April 14, 2018, 01:57:56 AM

I only need one input and don't need a volume or balance control.  So I an thinking that I would only install one set of RCAs, leave out the input selector, balance and volume controls and then run the RCAs directly to lugs 8 10 and 11.  Since I am leaving out the 100K volume pot it looks like that I would then have to connect 100K resister across each RCA.

Is all this correct?

Title: Re: Single input power amp
Post by: Paul Birkeland on April 14, 2018, 05:32:39 AM

That's the jist of it.  The balance control is still useful with zero feedback amps, as there can be some small channel imbalance. 

Title: Re: Single input power amp
Post by: crgolfer on April 14, 2018, 06:44:03 AM

Thanks for confirming my thinking.  I am not concerned about some channel imbalance as I will be running it from my dac which has volume and balance controls.

Is 100K the right value for the resistors or should I go to 133K to account for the resistor in the existing balance circuit?

Title: Re: Single input power amp
Post by: Paul Birkeland on April 14, 2018, 07:08:52 AM

Any resistor value between about 47K and 470K is going to do the job.  The stock volume pot/balance pot/resistors present something a bit more than 50K IIRC.

Title: Re: Single input power amp
Post by: crgolfer on April 14, 2018, 09:09:37 AM

Ok, thanks.