This is from your owners manual:
"Stereo Home Theater Pass Thru
The PrimaLuna DiaLogue Premium Integrated Amplifier is equipped with a home theater pass thru that
allows you to enjoy your stereo source material and the 2 main channels of your separate home
theater processor.
This is a true pass-thru circuit. Most integrated amps that advertise having home theater pass thru
circuits are only “unity gain” circuits. This means the volume is set at a pre-determined level, but the
preamp section is still active and can introduce unwanted noise and coloration to the sound. The home
theater pass thru of the DiaLogue Premium Integrated Amplifier completely removes the preamp
section from the signal path. This is a “direct-line” circuit that results in a lower noise floor, and less
coloration."
So it sounds to me like you can plug another preamp into your Home Theater Bypass inputs.
I would have the preamp and Primaluna turned off when you hooked them up and the volume on both preamps set to zero. Turn them on and slowly increase the volume on your separate preamp.
If you want to hear from someone who knows for sure, call Upscale Audio or another Primaluna dealer.
"Stereo Home Theater Pass Thru
The PrimaLuna DiaLogue Premium Integrated Amplifier is equipped with a home theater pass thru that
allows you to enjoy your stereo source material and the 2 main channels of your separate home
theater processor.
This is a true pass-thru circuit. Most integrated amps that advertise having home theater pass thru
circuits are only “unity gain” circuits. This means the volume is set at a pre-determined level, but the
preamp section is still active and can introduce unwanted noise and coloration to the sound. The home
theater pass thru of the DiaLogue Premium Integrated Amplifier completely removes the preamp
section from the signal path. This is a “direct-line” circuit that results in a lower noise floor, and less
coloration."
So it sounds to me like you can plug another preamp into your Home Theater Bypass inputs.
I would have the preamp and Primaluna turned off when you hooked them up and the volume on both preamps set to zero. Turn them on and slowly increase the volume on your separate preamp.
If you want to hear from someone who knows for sure, call Upscale Audio or another Primaluna dealer.