Kenwood/Sony Quadraphonic Setup Help Needed

[Cdemeo1]

Hey all. I'm trying to hook up my father's vintage quad stereo system. I'm home for the weekend and trying to wrap my brain around integrating the decoder. Probably overthinking it. Here is what he has:

• Kenwood KA-7002
• Kenwood KA-4002
• Sony SQ Decoder 100
• 4x JBL L100 (in-line version)

So how can I hook this thing up to get all speakers working in tandem? THANKS!!

- Both amps have pre-out/main in jacks.
- The KA-7002 has 4-Channel Inputs/Outputs
- The KA-7002 has two Tape Inputs/Outputs
- The KA-4002 has one Tape Input/Output
- The Sony Decoder back panel is shown below.



Ps. I joined the Quad forum but have been waiting for them to approve my request.

 

[1tumbleweed]

From deteriorating memory:

Follow the labels, left to right - REC OUT from tape out on 7002, TAPE IN to tape in on 7002, TO BACK AMP to any line level input on 4002 (aux is fine). No need to fool with the stuff to the right of the DIN connector (for now). Should work, but no guarantees!

Be aware, this won't do a whole lot unless you have some SQ-encoded quad LPs.

 

[Cdemeo1]

Well, I got it all working. Thanks for your help! Unfortunately there is a constant buzz coming from within the KA-7002 (not out of the speakers). And smoke started rising from the front of it. Good thing he just paid to have it "serviced" last fall. Haha.

It's an old amp and I know these components fail but I heard the buzzing when I was briefly home last winter. I tried to warn him back then to bring it back to them but being an older Viet Nam vet, he can't hear it. I know none of my techs back in SF would have never sent it out of their shops with that buzzing. Oh well. Going to see if he can take it back to them even though I'm sure they will say it's out of warranty.

 

[1tumbleweed]

First thing I'd look for with an internal buzz is the power transformer - although that doesn't square with "smoke rising"!

One thing I should have mentioned, with the tape monitor switch in normal position you're hearing the undecoded front channels; to hear the decoded front you need to have the tape monitor switch engaged. The back channels should always have the decoded back channel signal.

 

[tcdriver]

Hey all. I'm trying to hook up my father's vintage quad stereo system. I'm home for the weekend and trying to wrap my brain around integrating the decoder. ...

Congratulations on trying to get your father's quadraphonic system up and running. That sounds like a really nice system. I hope that you can get the amplifier repaired without too much trouble.

Once you get your amplifier repaired, you are in for a world of quadraphonic fun. Even if you do not have any SQ quadraphonic records, you can play ordinary two-channel stereo records through the decoder/system and get a synthesized pseudo - quadraphonic sound that can be quite pleasing.

 

[Doug G.]

I agree the buzzing sounds like an overloaded power transformer and the smoke may be from whatever is overloading it, if not from the transformer, itself, although that's probably unlikely.

Doug