Tube amp bias adjustment advice

@mmporsche 

you are biasing 'the first' set of tubes?

so new amp, or just new tubes in amp you have used for some time?  no channel imbalance before as you have been using this amp?

you need to clarify these critical contextual parameters to get any useful advice

You do not measure from the back of the speaker to the wall behind it. You measure from the front of the speaker to your nose at the sitting position. 

@needfreestuff I am following the instruction from the manufacturer.  I have single point source drivers, Voxativ 9.87.  I am centering myself between the speakers so the distance is the same so I am confused by your statement.  I find myself needing to sit about 2 feet to the right for it to sound balanced.  Both speakers have about 7' to the outside side walls.  

This is a second set of tubes, had the same issue previously so I am thinking it may be room acoustics. 

I will try swapping the speaker cables L to R and see if I notice any change.  

@mmporsche The first step is to swap the interconnect cables left for right at the inputs to the amplifiers so that you can determine if the amps are at fault. It could be something upstream.

If the problem stays put => amplifier problem
If the problem moves => problem upstream
If the problem stays put, swap the input tubes, not the power tubes. In this way no bias readjustment is needed. Most of the gain in the amp occurs in the input tubes so this is the most likely area to have a gain issue!

The bias will not affect the gain unless its a mile off! It affects *distortion* and usually at higher power levels.


Keep us informed of your progress.

"This is a second set of tubes, had the same issue previously so I am thinking it may be room acoustics. "
Had the same problem with center image staying in the center until I did room treatment. Problem solved.