Please educate me on vintage Marantz Quad gear...

adamp

New Member
I've had lots of vintage Marantz gear over the years, but have yet to dabble in 4-channel stuff.

There's a decently-priced (in my opinion) Model 4415 here at a local shop. It does not have the SQ decoder card thingy in the bottom of it.

Aside from the obvious 4 speakers and some quad records (another local record shop has a decent selection of used 4-channel records), what do I need to run this thing in quadrophonic mode? Does this require a special turntable, the SQ decoder, etc?

I understand there are different types of Quad records also, can someone explain the differences? I did a quick search of the forum on this model and didn't find anything.

Thank you,

Adam
 
A quick course in quad:

Discrete - via reel to reel or 8 track. 4 individual tracks, start to finish.

QS or RM - basic quad encode/decode format, does not require a special turntable. Will synthesize from stereo recordings with variable results, from adequate to "holy cow!".

SQ - The Columbia/CBS version of the above. Inferior, IMHO, to QS. YMMV.

If you never own an SQ LP, then you don't need the decoder.

CD-4 - "compatible discrete", developed by JVC. Requires CD-4 records, a turntable with low capacitance wiring and a CD-4 capable cartridge. Excellent, when it works. (sarcasm intended)

Your 4415 is a decent receiver, even without the SQ adapter. No CD-4 capability. 15w/ch, so not a lot of power. Nice as an example of classic Marantz, not so much as the best example of quad capability. What's "decently priced"?

Cheers,
Larry B.
 
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Thanks for the crash course, Larry!

So if I bought this 4415 and hook up 4 speakers to it, I can run a Marantz 6100 turntable into it using QS or RM LP's?

"Decently priced" in this case is $250 Canadian plus 13% sales tax for a total of $282.50, but the store owner said to make him an offer on it. I suspect if I waved $200 cash at him, it would come home with me. It's "reconditioned", but we all know that can mean anything from one or two burned lamps replaced and the controls deoxit-ed, to a full recap. I don't know exactly what work has been done to it, but the guy does have an experienced tech that works there full time so that's a decent sign.

Adam
 
Well, we're not supposed to discuss value anywhere other than "Dollars and Sense", but the lower figure sounds a whole lot better.

Bear in mind you'll need efficient speakers since you won't have power to spare.

QS and RM are essentially the same thing. QS is Sansui's trademark for their surround synthesizing algorithm, RM just means regular matrix, for companies that didn't want to give Sansui credit.

One of the fun things with QS surround is experimenting with LPs that aren't specifically encoded; the format depends on phase differences present in most stereo recordings. The more mics that were used in the original recording, the more likely surround effects are to be there. One of the best examples is ELP's Brain Salad Surgery; phenomenal sound in QS. Lots of other examples, too.

Have fun, and report back on your experience!

Cheers,
Larry B.
 
using QS or RM LP's?
the 4415 doesnt have a QS decoder. what it has is vari-matrix which simulates quad sound, using this you can play stereo records, QS, SQ, CD4 records and it will play them as quad but it will not most likely decode the quad albums the way they were recorded, if you want to play quad lps the way they were meant you will need the different decoders, the SQ plug in , a sansui QS decoder which would be a separate box/amp, for playing CD4 a CD4 demodulator and quad turntable and cartridge. probably a big reason why quad failed was too many formats. ive listened to my vari-matrix a few times and it does a pretty good job of simulating and sounds pretty good. i have a lot of quad LPs in all formats but i havent really tried to compare vari-matrix to SQ etc. with the same albums so i dont really know if there is a difference. maybe some day i will have time. i do think i like the CD4 format the best from what i hear though.

Love the meters like 4 smiley faces

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the 4415 doesnt have a QS decoder. what it has is vari-matrix which simulates quad sound, using this you can play stereo records, QS, SQ, CD4 records and it will play them as quad but it will not most likely decode the quad albums the way they were recorded, if you want to play quad lps the way they were meant you will need the different decoders, the SQ plug in , a sansui QS decoder which would be a separate box/amp, or a CD4 modulator and quad turntable and cartridge. probably a big reason why quad failed was too many formats. ive listened to my vari-matrix a few times and it does a pretty good job of simulating and sounds pretty good. i have a lot of quad LPs in all formats but i havent really tried to compare vari-matrix to SQ etc. with the same albums so i dont really know if there is a difference. maybe some day i will have time. i do think i like the CD4 format the best from what i hear though.


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Er, not quite. The 4415's quad circuits are virtually identical to QS in everything but name; they're not as sophisticated in terms of steering logic and separation, but they employ QS principles nonetheless. All matrix formats - QS, SQ, RM - are essentially "simulating" 4 channels, they're not discrete.

QS decoders can be found built-in to many receivers, not necessarily a separate box; a QRX9001 has as good a decoder as that format ever got. The QSD-2 was essentially the same in its own box.

IMHO, SQ responds the worst to decoding with anything other than their own - QS/RM OTOH does quite well. And of course CD-4 comes the closest to 4 discrete channels...when it works.

As always, just my opinion, YMMV.

Cheers,
Larry B.
 
I have three quad units, a Marantz 4270 that is being repaired now, a Kenwood KR-9940 and a Sansui QRX-7001.

The Marantz only does discrete quad, no built in decoder.

I *think* (I haven't seen it in a while, it's busted) that the Kenny does SQ/QS and has an optional CD-4 decoder card.

The Sansui has all formats built in, out of the box.

Other than CD-4 you don't need special low capacitance tonearm wiring or a special cartridge to get quad from a turntable.
 
The 4270, like the 4415, has Vari-Matrix (essentially QS/RM) built-in, with provision for the SQ box.

The Kenwood came standard with all three - SQ, RM and CD-4 - just like the 'Sui, although of course the QRX matrix decoding is superior to the Kenwood.

Cheers,
Larry B.
 
I'm not going to argue with you but my memory is that the manual for the Kenny listed it as an option, and it does plug into a slot in the back of the unit, as if it were user installable. Now they might have made a decision to sell all units with the decoder board built in.

The point that I was trying to make, of course, was the same as you stated, the Sansui in my opinion is superior, and can often be found for less than an equivalent Marantz (although the 8001 and 9001 are finicky and have double sided boards which often need to be "pinned" to work reliably) which is why I sought it out. The Kenny was a thrift store find, and the Marantz was given to me by a friend and I plan on using it for 2 channel when it comes back as it does not have the SQ board (you can bridge the amps and turn it into a 75WPC stereo receiver)
 
No argument. Indeed, the owner's manual and the Buyers' Guide contradict each other - the manual says it's an option, the Buyers' Guide says it was standard.

So, no worries, you may be correct - although one would think that for nearly $1000 in 1975 dollars it would have included the CD-4 board.

I'll stand by my statement that nothing - NOTHING - beats a properly functioning Sansui QRX series for decoding of all formats.:music:

Cheers,
Larry B.
 
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