CD-4 Test Record

[Stiffgriff]

I finally have my CD-4 quad system working. Now I’m ready for a CD-4 test record to calibrate properly. I see there’s quite a few differently branded test records on eBay. My set up is all Marantz (4270, 6200, CD-400B). Does it matter which one I buy or do I need specifically a Marantz (the most expensive obviously) one? Thanks!

 

[J. PUPSTER]

I finally have my CD-4 quad system working. Now I’m ready for a CD-4 test record to calibrate properly. I see there’s quite a few differently branded test records on eBay. My set up is all Marantz (4270, 6200, CD-400B). Does it matter which one I buy or do I need specifically a Marantz (the most expensive obviously) one? Thanks!

Hello again Stiffgriff!

Your Marantz should have come with a calibration disc like these-

https://www.discogs.com/release/5251789-CD-4-CD-4-Calibration-Disc

I also like this Lou Dorren LP-

https://www.discogs.com/release/154...-4-Quadradisc-4-Channel-2-Channel-Test-Record

probably a good idea to call up some other experienced guys here on CD-4 for rec's.

@fredblue and @Doug G.

 

[par4ken]

I finally have my CD-4 quad system working. Now I’m ready for a CD-4 test record to calibrate properly. I see there’s quite a few differently branded test records on eBay. My set up is all Marantz (4270, 6200, CD-400B). Does it matter which one I buy or do I need specifically a Marantz (the most expensive obviously) one? Thanks!

You can use any CD-4 test record. The CD-400B has an automatic carrier level so requires no adjustment there to complicate things. You just have to do the separation adjustment. In the service manual they are using the JVC test record.

 

[Stiffgriff]

You can use any CD-4 test record. The CD-400B has an automatic carrier level so requires no adjustment there to complicate things. You just have to do the separation adjustment. In the service manual they are using the JVC test record.

Thanks! I’m looking at this one on eBay currently. Should be fine?
https://www.ebay.com/itm/3872506948...IKoaZeWTRa&var=&widget_ver=artemis&media=COPY

 

[Doug G.]

I have several CD-4 test records. The Harman Kardon (made by RCA) is my favorite but they all work. The Lou Dorren/Brad Miller disc is great but be aware of some errors on it.

And, congratulations on your CD-4 system. It's a great format.

Doug

 

[jwb474]

Hello again Stiffgriff!

Your Marantz should have come with a calibration disc like these-

https://www.discogs.com/release/5251789-CD-4-CD-4-Calibration-Disc

I also like this Lou Dorren LP-

https://www.discogs.com/release/154...-4-Quadradisc-4-Channel-2-Channel-Test-Record

probably a good idea to call up some other experienced guys here on CD-4 for rec's.

@fredblue and @Doug G.

Shoot, I would just buy a Marantz CD-4 Cal disc from one of the Discogs sellers. That way you have a official disc to compliment your setup.

 

[gvl_guy]

I found that one of my favorite CD-4 test records was this one. And, you can often find it for around $20 on eBay. Two things: it's 33 1/3 rpm, not one of those crappy 45s. And Warner included lots of great songs on the album with some awesome quad effects. A win-win.
https://www.discogs.com/release/445...Present-CD-4-Channel-Demonstration-Quadradisc

 

[Doug G.]

Yeah, that's a good one and has what I consider the best quad cover, ever.

I forgot to mention I like the 33 rpm records better, too. As gvl_guy indicated, the 45 rpm records are usually poorer. They are usually warped and generally, just don'e track as well.

Doug

 

[Owen Smith]

Since all actual CD-4 content is at 33rpm, I'd have thought it makes sense to calibrate with a 33rpm record anyway even if there weren't problems with the 45rpm records warping.

 

[par4ken]

Since all actual CD-4 content is at 33rpm, I'd have thought it makes sense to calibrate with a 33rpm record anyway even there weren't problems with the 45rpm records warping.

This might just be a false memory but I seem to remember a test report where they were able to get the "radar" light to come on steady using a regular stereo cartridge with the 45 rpm test record. So perhaps the higher speed allowed for more ultrasonic output from the cartridge. That might make initial adjustment easier, but would it match with tone levels from an actual 33.3rpm CD-4 album?

I suspect that the real reason they supplied a 45 test record is that it fit into the smallish CD-4 demodulator box, an LP would have to be supplied separately.

 

[fredblue]

I found that one of my favorite CD-4 test records was this one. And, you can often find it for around $20 on eBay. Two things: it's 33 1/3 rpm, not one of those crappy 45s. And Warner included lots of great songs on the album with some awesome quad effects. A win-win.
https://www.discogs.com/release/445...Present-CD-4-Channel-Demonstration-Quadradisc

isn't this one of those 33's with wooooooshinggg white noise rather than the usual woowoowoowoo warble tones of the setup 45's?

if so, i found it harder to really nail front to back separation with the white noise wooshy woosh than the wah wah warble warb!

great track selection though!

 

[Owen Smith]

I suspect that the real reason they supplied a 45 test record is that it fit into the smallish CD-4 demodulator box, an LP would have to be supplied separately.

You are probably correct.

Best audio quality for a CD-4 test record would be a 12" single ie 45rpm, but I'm not aware of any.

 

[Doug G.]

The speed of the actual record doesn't matter if the same material is engraved into the grooves. The frequencies seen by the stylus is the same. It's just that the 45s didn't seem to be manufactured as well.

The Warner record does, indeed, use white noise instead of a steady tone (Harman/Kardon) or warble tone (Popular Science) and I agree, it's harder to use when just listening to it to adjust separation. The SH-400 has a meter so it doesn't matter with that demodulator.

I agree that the reason for the 45 rpm records included with demodulators was because of size and also, cost.

Doug

 

[kfbkfb]

I use headphones to adjust the F/B separation - LF to (stereo) L and LB to (stereo) R, adjust until the stereo effect seems good (may not result in the highest separation though) and do the same for RF and RB.


Kirk Bayne

 

[par4ken]

I use headphones to adjust the F/B separation - LF to (stereo) L and LB to (stereo) R, adjust until the stereo effect seems good (may not result in the highest separation though) and do the same for RF and RB.


Kirk Bayne

I have done that as well, but if you try it with music instead of a test tone it is difficult to tell the proper setting. Adding too much of the difference signal makes the sound image sound bigger (widder) via phones! I prefer a steady test tone for adjustment. Also I feel that with every test record stereo or CD-4 the tones are usually of much too short a duration.

They could have easily made an adjustment record with a tone that covered almost the full side of the LP that would have given you plenty of time to fine adjust the setting and you could easily check/adjust the operation/performance on those troublesome inner grooves as well. They could have even done left on one LP side and the right on the other!

 

[gvl_guy]

The worst part about ALL of them (well, most) is that the tones don't last long enough for the adjustment.

And the 45s must be pressed crappy because they all seem to crackle and pop more than Dad's old Mitch Miller records.