WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
Building, troubleshooting and testing of these amplifiers should only be
performed by someone who is thoroughly familiar with
the safety precautions around high voltages.
I have an integrated tube amp which does not have a set of subwoofer outputs. Could I use Y-adapters on the chassis mounted line in RCAs which I currently connect to my CD player, and use that signal to my subwoofer plate amp? Will this work?
It will probably work if you are controlling the volume via the CD player. If not, you will be feeding an unattenuated (full loud) signal to the sub. You'd also want to check that the input impedence of the sub amp in parallel with the input impedence of your main amp is ok for your CD player.
I think many sub amps can take a speaker level input. Check to see if yours will.
I checked both my amps and one of them does indeed show speaker level inputs ( and line level input) whereas on the other amp has it labelled "high level in" as well as having line in. I assume that high level input actually means speaker level input. Anyway I will try what you suggested and see how it works.