Anyone ever use a Dynaco Quadadapter QDP-i

I just picked up one of these old Quadraphonic simulators and I wonder how best to use it. How much power can it handle? How does it effect  impedance when using four speakers? How much does it degrade performance and does it matter?


It is a very simple circuit.  Basically you run a wire off of each channels positive output and run it through one or two rear speakers (in series) and throw on a volume control.   You need the rear channels placed as far back as you can to add some delay.  Used it once 20 yrs ago for "home theater" off of my two channel system.  I was quite surprised at how natural it sounded if you can set it up right.  I would guess the added demand on the amp is minimal.

I owned and used one when they were new- maybe 1977 or thereabouts. I recall from the user manual the recommendation that all 4 speakers have similar efficiency and impedance ratings. And- the powering amplifier must have (or use) a common ground between channels. Most do, but it is important to verify!

I really enjoyed my time using the qd-1, especially with certain albums. At the time, I was using Dynaco speakers. I may still have the original owners guide…