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    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Audio Research Ref 75

Hello - I have an Audio Research Ref75se (stereo) and I'm thinking about getting another one and using just one-channel in each amp. This will allow me to get the amps closer to the speakers and have backup components and tubes for the long run. I don't have a circuit diagram but I would think that removing the input tube and output tubes on the channel I'm not using would be fine. If there is a connector/fuse from the power supply for each channel that would also be disconnected. Anyone have experience/thoughts on this. Thanks
 
Take out 2 power output tubes?

Unless the B+ is regulated, B+ voltage will increase.
And, before the B+ the regulator input, the B+ voltage to the first and second filter caps will increase; what are their voltage ratings versus the new higher B+ voltages to the caps?
Will the B+ regulator like the increased B+ voltage at the regulator input?

Unless B+ is regulated, it will increase the voltage to the remaining input tube.
Will it operate with the same linearity?

Or, IF there are two completely separate power supplies on one stereo amplifier, the above answers do not apply.
Just disable one of the two power supplies.
You said there are separate fuses, the question is, are they in the power mains circuits of separate power supplies?

Common filament supplies? If so . . .
The filament voltages to the remaining tubes will increase.
Will it be in spec. for the remaining tubes?

Just my concerns.
 
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Hello - I have an Audio Research Ref75se (stereo) and I'm thinking about getting another one and using just one-channel in each amp. This will allow me to get the amps closer to the speakers and have backup components and tubes for the long run. I don't have a circuit diagram but I would think that removing the input tube and output tubes on the channel I'm not using would be fine. If there is a connector/fuse from the power supply for each channel that would also be disconnected. Anyone have experience/thoughts on this. Thanks
You just might be better off purchasing a pair of dynaco MkIII and use for that purpose, save the AR ( or sell it)
 
Depending on the WAF (Wife Acceptance Factor), put one stereo amplifier at the back wall, in the middle between the 2 speakers.
The 2 speaker cable lengths are only 1/2 of the distance between the speakers.
I saw that at Consumer Electronics hotel "show rooms" all the time.
And, you have a spare stereo amplifier if one needs to be serviced.