Lafayette LR-4000, JVC VL-5 CD-4 and SQ setup

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jsetche

New member
Joined
Aug 10, 2004
Messages
7
Location
Advance, NC
I am setting my quad system that my grandfather purchased in the early 70s. I have found myself quite confused and need help. I have a Lafayette LR-4000 receiver, a JVC VL-5 CD-4 turntable with a JVC 4MD-20X cartridge, and a JVC 4DD-5 CD-4 demodulator. I also have on order a Pro-Ject 1Xpression Carbon Classic turntable with a Hana MC low output Shibata cartridge. I am fairly certain I need a preamp for the Pro-Ject table. My questions are: Will it work properly if I connect the pro-ject table to a CD-4 demodulator? Do I need a preamp for either turntable and if so, where in the chain of connections does it go? Any advice on how to best hook up all this gear is genuinely appreciated. I also have a Lafayette RK-48A 8-track player and an Akai GX-280D-SS reel-to-reel but those seem a bit more straightforward. Pix included of most of the gear. Thank you for your help!
 

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First, if you haven't already verified that everything is functional, please do so. Non-functional pieces will likely need capacitors replaced at the minimum. 4DD5 is likely to need work.

LR-4000 has an internal MM phono preamp. It will also has an SQ decoder and will decode other matrix systems, as well as synthesize Quad from 2 ch. It can be set for magnetic (MM) or ceramic (cheapo) cartridges. Although it was only sold by Lafayette, it garnered sparkling reviews in the hi-fi magazines. It features a full-logic wavematching SQ decoder which was one of the reasons it got high marks. It was their flagship model.

As to phono cartridges, the JVC is a standard output cartridge. It will need no additional preamplification through the 4DD5 or LR 4000 phono input.

The 4DD5 has an internal phono preamp. The 4DD5 Quad output is preamplified. The switch next to 2 channel direct out will allow either a 2 ch pass through WITHOUT preamplification OR WITH preamplification, depending on the setting.

Hana model SL is MC w/Shibata low output. Both models E & S are available as high or low output. SL will need a transformer or pre-preamplifier to boost the signal. Likely you knew all this.

BOTH cartridges should be able to reproduce extremely high frequencies for CD-4 demodulating.

Here's what David at Audio Karma had to say about the turntable:
Watch the tracking on that model. I sold them back when new. There was a run of them that had binding tonearm bearings. You'd notice it as the arm tracked across the LP.

In this case, the stylus would 'walk' out in front of the cartridge. That is, the tonearm would not follow the stylus in the groove and eventual mis-tracking would occur.

This was due to the bearing race at the bottom of the tonearm being too tightly bound. You'd have to remove the tonearm, break the sealed double-lock-nut and then retighten the nut on the bearings. We had a number of them returned until JVC USA figured out what the problem was. They never issued a service bulletin, though.

Got a fair amount of warranty money once I figured out what the problem was, too.
 
Wow! Thank you Quad Linda for your thorough response.

So if I were to use the pro-ject table with the hana MC cart to play CD-4 LPs, would I connect the turntable to an MC preamp and connect that to the 4DD5 and then to a 4 channel aux input on the LR4000?
 
You're welcome.

The transformer or prepreamp needs to pass a very high frequency for CD-4 to demodulate properly. Something like 40,000hz. I have an Ortofon MC prepreamp that actually has a CD-4 setting on the front. It's called MCA-76. I got it in '79. It is an active device that needs 110 to power it.

If you're taping in 2ch off a CD-4 record, you'll probably want to turn it's multiplex (mpx) filter on if the tape deck has one. Otherwise, the tape might record the CD-4 carrier which will be audible. How audible? It depends on the high-end frequency response of the deck.

And get a CD-4 adjustment record. It will make it easier to adust.


Wow! Thank you Quad Linda for your thorough response.

So if I were to use the pro-ject table with the hana MC cart to play CD-4 LPs, would I connect the turntable to an MC preamp and connect that to the 4DD5 and then to a 4 channel aux input on the LR4000?
 
You're welcome.

The transformer or prepreamp needs to pass a very high frequency for CD-4 to demodulate properly. Something like 40,000hz. I have an Ortofon MC prepreamp that actually has a CD-4 setting on the front. It's called MCA-76. I got it in '79. It is an active device that needs 110 to power it.

If you're taping in 2ch off a CD-4 record, you'll probably want to turn it's multiplex (mpx) filter on if the tape deck has one. Otherwise, the tape might record the CD-4 carrier which will be audible. How audible? It depends on the high-end frequency response of the deck.

And get a CD-4 adjustment record. It will make it easier to adust.

Ok got it. And thank you. So assuming all things work properly, would it make most sense to connect JVC table to demodulator and to LR-4000. And then connect pro-ject with hana to a MC preamp and then to LR4000 for SQ/QS formats?
 
Got most of everything connected. Stopped short of connecting JVC Cd-4 when I got massive hum and an overpowered right channel. Determined it was preamp so that is on it's way back and being replaced with a Musical Surroundings Phonomena II+ Phono Preamp. Pix below. And thanks again.
 

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Just wondering if you got the system to work! To get it to work properly I hope you got your hands on the JVC setup disk!
 
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