ELP Turntable - Ask Me Anything!

[fredblue]

Which one Freddie, a Shibata on a AT440Mlb?

i found the 440MLb (MicroLine) the most consistent out of those i've used with CD-4, relatively few discs go really awry with it.

the AT15S (Shibata) is great on certain CD-4 discs but quite a few of my favourites trip it up and wow is it a heavy cart (and irrational as it may seem that extra weight worries me!) compared to all my other plasticky cartridges its a chunky beast (got 4 headshells on the go at the min., 7 carts in all but the 2xellipticals and 1xconical don't get used at all now).

the JVC 4MD10x i concluded was nigh-on useless unless i tracked it at +2g and i wasn't prepared to do that.

oh and i couldn't get the Denon DL-110 that someone suggested works for CD-4 to work properly (it would often lose the 30kHz carrier on discs the 2xAT's never did).

 

[gvl_guy]

I never had CD-4 issues back in the day. I was using a Shure M24H, Technics turntable and a demodulator in a Pioneer QX-949a. No problems. After my receiver died, lots of moves in life, and putting my turntable in mothballs for many years, I'm back at it! I purchased a Sansui QRX-7001. Same turntable, same cartridge, new stylus. Nothing but issues. Even bought a NOS JVC 4MD-20x cartridge. Similar issues. Bought a NOS JVC demodulator to try. (It's being serviced now as it wouldn't power on. ). Frustrating. Some albums sound ok. Others are pure garbage.

 

[MidiMagic]

Might check to see if the damping lubricant (if any) in the arm bearings or the velocity trip has gotten stiff over the years.

I had to relube many Garrard turntables from the '60s and '70s because of this problem.

Another thought is that the cantilever support in the stylus (NOS) has become stiff with age.

Were the albums played with a stereo pickup during that dormant period?

 

[gvl_guy]

I had the turntable worked on, lube, etc. Seems okay. No, I never really played the albums much when I put them away. So it shouldnt be that. Some used ones I recently purchased I can understand the issues, but not with my own. I was always super careful. It's just frustrating. I'm actually liking the matrix albums better. Even some stereo ones sound amazing using the Sansui "synthesize" mode.

 

[Jerfo]

Hey guys!

I wanted to give you a quick update on my progress with CD-4 LPs using the ELP. I've hit a few roadblocks. Most notably, the right channels on my JVC 4DD-5 demodulator aren't working properly. I can get them to output identically (basically a mono sum of both right channels), but no amount of separation adjustment gets them to give me their individual output. I had a look through the service manual, but I didn't find any immediate answers and I don't have the spare time right now to dig through the schematic and start some systematic troubleshooting. So, hardware demodulation testing isn't an option for me at the moment. If anybody is selling a working demodulator, shoot me a note.

I've shifted my efforts to the software side. I purchased a full copy of the PSpatial Stereo Lab software, which has a couple of software-based CD-4 demodulation options. My results have been mixed. My 24/96 rips from the ELP all appear to be showing a strong carrier signal and they sound great in stereo, but somewhere in the process (probably in the anti-RIAA VST I'm using) I'm losing carrier strength and/or general audio fidelity. I'm going to try using Stereo's Lab's own anti-RIAA filter to see if that's an improvement. I'll keep you guys posted. I'm determined to make this square peg fit into this round hole.

On a more positive note, I'm currently listening to the Pharoah Sanders LP "Black Unity" on the ELP running through the Surround Master and...holy smokes it sounds amazing. If you aren't familiar with the album, there are parts that are very dense with jubilant squawking brass instruments. The ELP / Surround Master combo is unfolding everything into its own space and it's like sitting on stage in the middle of all these musicians. Just awesome.

 

[winopener]

I've shifted my efforts to the software side. I purchased a full copy of the PSpatial Stereo Lab software, which has a couple of software-based CD-4 demodulation options. My results have been mixed. My 24/96 rips from the ELP all appear to be showing a strong carrier signal and they sound great in stereo, but somewhere in the process (probably in the anti-RIAA VST I'm using) I'm losing carrier strength and/or general audio fidelity. I'm going to try using Stereo's Lab's own anti-RIAA filter to see if that's an improvement. I'll keep you guys posted. I'm determined to make this square peg fit into this round hole.

May i suggest a different approach?
I see that the Basic has both LINE OUT and PHONO OUT available, of course the LINE OUT does carry the internal RIAA processing you're trying to avoid.
So, connect the PHONO OUT to the two MIC IN of your soundcard or to a 2- CHANNEL MIC AMPLIFIER that is similar about impedance in order to raise the level to a value acceptable for your sound card, and sample it that way.
THEN, in software, you can apply the needed Riaa eq and pass it to the cd4 software demod. IIRC the Pspatial site has also a pair of schematic of a modded phono stage for that purpose (raise level without the riaa eq).

 

[Jerfo]

May i suggest a different approach?
I see that the Basic has both LINE OUT and PHONO OUT available, of course the LINE OUT does carry the internal RIAA processing you're trying to avoid.
So, connect the PHONO OUT to the two MIC IN of your soundcard or to a 2- CHANNEL MIC AMPLIFIER that is similar about impedance in order to raise the level to a value acceptable for your sound card, and sample it that way.
THEN, in software, you can apply the needed Riaa eq and pass it to the cd4 software demod. IIRC the Pspatial site has also a pair of schematic of a modded phono stage for that purpose (raise level without the riaa eq).

That's the current gen model. My model doesn't have the option of switching between the two.

[Additional edit for clarity - the LT-1LRC model only has a single set of RCA outputs. Most of them are phono-only, but mine happens to be a line level output. It was a special-order option when this was the current gen model. There's no switch for going back and forth between phono and line level.]

 

[Jerfo]

Another quick update for y'all:

I'm still waiting on my passive anti-RIAA filter to show up. In the meantime, I've managed to get my hands on a new-to-me CD-4 demodulator: a Marantz CD-400B. I've cobbled together a testing setup by doing the following:

1. Digitizing a CD-4 album from the laser turntable at 96/24.
2. Applying an inverse RIAA filter in my DAW
3. Feeding this output back into the CD-400B

It works brilliantly! I've tested it on my CD-4 calibration record, Flora Purim's "Stories To Tell," and FZ's "Apostrophe." Each one of them gives me a nice solid RADAR light on the CD-400B, with beautiful channel separation and none of the CD-4 artifacts that we've all grown to...um....appreciate over the years. I wish that I could get such nice results from the Stereo Lab software, but that's a problem to tackle another day.

I'm in the middle of working on a YouTube video about the turntable. I'll share the link here when it's available.

 

[fredblue]

Another quick update for y'all:

I'm still waiting on my passive anti-RIAA filter to show up. In the meantime, I've managed to get my hands on a new-to-me CD-4 demodulator: a Marantz CD-400B. I've cobbled together a testing setup by doing the following:

1. Digitizing a CD-4 album from the laser turntable at 96/24.
2. Applying an inverse RIAA filter in my DAW
3. Feeding this output back into the CD-400B

It works brilliantly! I've tested it on my CD-4 calibration record, Flora Purim's "Stories To Tell," and FZ's "Apostrophe." Each one of them gives me a nice solid RADAR light on the CD-400B, with beautiful channel separation and none of the CD-4 artifacts that we've all grown to...um....appreciate over the years. I wish that I could get such nice results from the Stereo Lab software, but that's a problem to tackle another day.

I'm in the middle of working on a YouTube video about the turntable. I'll share the link here when it's available.

wow that sounds amazing!!!!

does the 30kHz tone on your calibration disc have a mellifluous 'rounded' sound or a harder-edged "meep"?

also, on channel check material, is total separation achieved in each channel or does some faint trace of another channel remain?

 

[Jerfo]

does the 30kHz tone on your calibration disc have a mellifluous 'rounded' sound or a harder-edged "meep"?

I couldn't tell you. My hearing tops out at like 28kHz these days.

Wise cracks aside, I honestly didn't pay much mind to how the tones on the calibration disc sounded and was just happy that they were bleeping out of the correct speakers. I'll give it another listen after work and attempt to describe using my best audiophile verbiage.

also, on channel check material, is total separation achieved in each channel or does some faint trace of another channel remain?

This one I did make a note of: there was surprisingly a trace of the other channels even after making my level adjustments. I've gotten my hands on another calibration disc and I'll see if the results are similar.

 

[MidiMagic]

I have never seen any quadraphonic system that could totally null out a channel. I can't even do it with a mixer. There is always a slight residue.

You don't need an inverse RIAA filter. Use a graphic equalizer.

 

[fredblue]

I couldn't tell you. My hearing tops out at like 28kHz these days.

Wise cracks aside, I honestly didn't pay much mind to how the tones on the calibration disc sounded and was just happy that they were bleeping out of the correct speakers. I'll give it another listen after work and attempt to describe using my best audiophile verbiage.


This one I did make a note of: there was surprisingly a trace of the other channels even after making my level adjustments. I've gotten my hands on another calibration disc and I'll see if the results are similar.

haha!! tbh the pilot tone questions a leading one because i have had that 30kHz tone nigh-on ringing like a bell and the demodulated results were shall we say "inconsistent".. and then i've had it meeping and squawking and screeching and the same discs demodulated better/with less or no distortion.

kooky old system CD-4, just when you think you've got it sussed something rears its ugly head!

 

[JediJoker]

Yes! I've ripped the first side of the album "Better Than Live" by Larry Coryell and The Brubeck Brothers for your listening pleasure. It was a direct to disc recording from 1978 that has never been re-released and it's unlikely that it ever will, so I don't feel too terrible about sharing it. You can download them from my OneDrive link here: ELP Rips . The sounds clips are 24/96 and completely unedited - no click removal, no normalization, no limiting, etc.

Wow... Aside from a few instances of surface noise, I would not have guessed this was a vinyl rip. Sounds great! Does the ELP have quartz lock?

 

[Jerfo]

Does the ELP have quartz lock?

That's an interesting question! There's no button for it like you'll see on certain turntables. That said, I'm not sure what it's doing underneath the covers to ensure accurate and consistent rotational speed. If and when I open the turntable up again, I'll search the PCB for a quartz oscillator.

 

[abby normal]

could you post the other side of that album por favor? i am NOT going to get that level of audio purity from my setup.

 

[Plan9]

could you post the other side of that album por favor? i am NOT going to get that level of audio purity from my setup.

I came here to ask the very same thing!

 

[abby normal]

I came here to ask the very same thing!

great minds think alike

 

[kfbkfb]

I was wondering if the ELP turntable is able to play the "problem"
CD-4 titles without as much distortion (the laser may be able to
retrieve the instantaneous carrier frequency correctly, this post
shows the problem):

https://www.quadraphonicquad.com/fo...software-demodulator.24900/page-7#post-432375

Kirk Bayne

 

[Jerfo]

could you post the other side of that album por favor? i am NOT going to get that level of audio purity from my setup.

As long as the mods / admins don't mind my doing so. It's technically copyrighted material, but it's also something that hasn't been re-released for 40+ years. I don't think I'd be depriving the artists of any profits by posting it.

 

[JediJoker]

As long as the mods / admins don't mind my doing so. It's technically copyrighted material, but it's also something that hasn't been re-released for 40+ years. I don't think I'd be depriving the artists of any profits by posting it.

I would say: don't post the full album here in this thread.

Anyone who's interested in hearing the rest: send @Jerfo a private message.