Combination DMM, LP-45 and CD-4 QuadraDisc.

[diamone]

Since there's no forums on here exclusive to DMM, exclusive to audiophile 45-LP or exclusive to CD-4 we decided to post this in Experimenters - even though the research is pretty much complete on it:

If anybody is serious about wanting to sponsor a new combination DMM LP-45 CD-4 project -

My colleagues and I have been researching this for about the past seven years or so - and we think either with one of the latter-day (1977) 2/3rd speed CD-4 cutterheads Greg Bogantz worked with - or the Ortofon prototype they made exactly six of in Scandanavia in 1979 -

we could have them converted to DMM -

get a VMS-82/84 lathe and in the process become the only commercial mastering house in America (besides Scientology) to even HAVE DMM in the FIRST place even for NORMAL cutting (which could also help raise money for the CD-4 DMM project) - and then

Attract the non-CD-4 audiophile market as well with cutting at 33 to play back at 45 the same way that both covers the same guys that would buy Half-Speed-Masters (if they made them) as well as the Super-Sonic 45-RPM formats that split a single LP over 4 sides.

But with DMM we wouldn't HAVE to split it up over two discs, so then it would keep the cost down to a reasonable amount since DMM can give you a side length of up to 35 mins for 33 without MUCH loss of quality - at least for which the 45 RPM speed wouldn't make up in one fashion or the next - which means roughly 23 minutes at 45 - enough time for the vast majority of single-disc LP's.

The reason we think the Ortofon would be the better choice of the two if we could get the tech drawings and all the final engineering designs - is because the Ortofon half-speed-masters on LACQUER in the 70's were so much clearer sounding than those made on either the Westrex or Neumann - partly because the bass contour effect - while there - is about half that of the Neumann or Westrex heads - at least according to a handful of engineering testimonials we found.

After re-setting the NAB and RIAA curves - if you play back a 15 IPS master on a MUZAK machine (that we already have in an all-tube 350AG) at 11-1/4 IPS we cut at 33 for 45 playback to avoid having to use more non-standard equipment than we have to and waste money.

The speed percentage (74.0740740... and 75.00) is not much different than the speed between US 45's (45.00) and 78's (78.26) and those made in 50Hz/220V countries which are 45.45 and 77.92. Which if guys thought there was that big of a difference, since presumably they'd all be on audiophile turntables with pitch adjust - we could put a strobe around the edge of the label with the exact speed - and then have the first disc be full of test tones and generic music that we give away.

AND the 2/3rds cutting speed that was already proven successful in 1977 before CD-4 died, (in this case pushed up slightly from 66.6666% to 75% speed) eliminates or greatly minimizes the bass contour effect inherent in half-speed mastering.

And then the Seeburg background-music jukebox people we know want to use DMM to re-cut all the Seeburg, Rowe (CustoMusic) and AEI 16-RPM nine-inch discs with the two-inch-hole - and the 7-inch 16-RPM Chrysler Highway Hi-Fi, and the Auto-Com 16 RPM flexidiscs and on and on and on people - all of whom want it pressed onto colored vinyl that matches the original label color - that they all need for their specialized custom players that they keep running 30 years after the format was withdrawn - like the 78 RPM re-issues Len cut for Rhino back in the 90's for ``jukebox use'' even though nobody with a brain actually used `em thereon.

And we also found out that even though the DMM mechanical chatter is around 30KHz - which means even if you COULD cut CD-4 in real-time on DMM - the chatter would wreak havoc with the carrier wave. but again - the law of mathematics comes to our aid here as well because according to our various math geniuses - the 30KHz chatter would still be 30KHz matering at 33 for 45 playback as it would be for 33 for 33 playback.

Meaning your 30KHz mechanical DMM chatter would not only NOW be 45KHz but it would also be DOWN 10 or 20 dB as well compared to 33 for 33 playback - and the 30 KHz CD-4 tone being recorded would now be 22-1/2KHz - supposedly well out of the way of one another.

So there IS a market for it - we just need more than one sponsor - and we need to get all the sponsors all on the same page to

get the DMM lathe in the first place -

get the drawings to the Ortofon head -

pay Len Horowitz or Flo or whoever to re-design it to match or exceed the six prototype heads from 1979 -

do the same for the Quadulator -

pay a couple of the few remaining DMM engineers in the world
to come work with the few remaining CD-4 engineers in the world
to come work with the few remaining half-speed-master guys

and then go ``on the air'' and understand that we'd be using the thousands-of-sides from the CustoMusic etc libraries as training grounds to A) raise money and B) get a good handle on the process, tweaking as we go before we start doing the DMM CD-4 33-for-playback-at-45 records.

So like I said - if anybody can help with sourcing equipment, documentation or sponsorships and is serious about wanting to sponsor some new DMM/CD-4/45-LP technology - drop us a line.

[diamone]

Most of the research-to-date can be found here:
https://lathetrolls.com/viewtopic.php?f=15&t=4350&p=27603#p27603
Other related research is scattered in other threads.

[flozki]

well a lot of things to reply.
i like people freaking in different directions. althought i think most people on this forum know my opinion about dmm. but i like to support where i can.

a few real problems. especially if you want to do the project in usa.

1. blanks. big big problem. at the moment i dont know any source of constant high quality blanks. sometimes they are useable. sometimes not. most of the inhouse dmm blanks might be quite good. but they are good if produced. freshly used in the cutting room in the same location and then immediately taken to the the galvanics.
i think those blanks are easy to make.
i had the luck to work with last batches of original teldec, nordorf blanks.and then they stopped or someone took over i dont know the actual status. we experimented at that time with all kind of alternatives. there where about 3-4 alternatives. but they never came to same quality.
and i think its not better today. the heavy dmm users do all inhouse, non stable cooper. the smaler studios have to take what they get. as far as i kno its only MPP in germany producing dmm blanks right now. and quality is from great to whatever. so difficult.

2. to get a dmm lathe back to usa. i dont thinkg that is possible.
maybe easier and cheaper to go to one of those balancer stores of the CHURCH and ask for a membership.....

3. the speed problem is not a problem. the issue of 45 and 45.xx whatever in europe was only the case for lyrec motors.
most professional studios in europe use technics motor or a vms80/82 where all is quarz locked.

4. good news about dmm stylii. there is a new high quality german source. so no problem there.
what i heard was that this one was recently tested on a real dmm machine with blanks...with great results.

so let me know if you get the plans. i definitely can get it produced by prototype mechanics. we have them all around.
and do all the winding and testing.
i am not really fan of ortofon design. it might include expensive tools for the coil producing. but lets see the drawings first.
and also i wondering how the ortofon stylus holder looks like. this is a key issue. hopefully they used the same as neumann. but i dont think so.

[diamone]

well a lot of things to reply.

Many of your responses were themselves responded to in the other thread here: https://lathetrolls.com/viewtopic.php?f=15&t=4350

i like people freaking in different directions. althought i think most people on this forum know my opinion about dmm. but i like to support where i can. a few real problems. especially if you want to...

but one of the reasons we want to do this is to EVENTUALLY

do the project in usa.

Obviously that's not in the cards for awhile at least - so we have to take whatever help and advice we can get from wherever we can get it.

1. blanks. big big problem. at the moment i dont know any source of constant high quality blanks. sometimes they are useable. sometimes not.

There's a place in ultra-rich Marin County just across the bridge to the north where a guy who's a big DMM fan of the pressings says he can get his medical equipment suppliers to provide consistent high-quality blanks - although they're never going to be two-sided as on a lacquer - making it expensive to `blow a side'

But be that as it may - as we continue to explore the medical-equipment-supplier vein of this (as well as whatever other avenues we find), we'll have to see how ``reliable'' they are vs trying to use the ones used by GZ which are yes cheaper (not counting the horrendous shipping charge - another reason for making them in the Bay Area)...

most of the inhouse dmm blanks might be quite good. but they are only good if produced, freshly used in the cutting room in the same location and then immediately taken to the the galvanics.

Which is another reason we already know about - same as lacquers are best if around a month old (gives them time to set up) and then cut and plated within hours of one another.

i think those blanks are easy to make. i had the luck to work with last batches of original teldec, nordhorff blanks.and then they stopped or someone took over i dont know the actual status. we experimented at that time with all kind of alternatives. there where about 3-4 alternatives. but they never came to same quality.
and i think its not better today.

Yes, we found that out the hard way - but like you we got lucky a couple of times with the LAST batch of experiments and got a couple of leftover blanks that were ``below standard'' for I can't remember now if it was EMI or The Exchange or whatever - but we got like five donated to us a couple of years ago - shipped over in cold packs - and then (at the time) we were able to get Scientology to run some tests on `em - even though we ourselves weren't allowed on Gold Base in Hemet CA where the mastering lab is - they were able to take our normal stereo material and cut on these five donated European discs and at least grade them in case we could afford to buy `em sometime in the future.

Well they were all passable according to the mastering engineer there, but three were music-worthy and two were not i.e. they'd have used them for mastering LRH speeches but nothing else.

the heavy dmm users do all inhouse, non stable copper. the smaller studios have to take what they get. as far as i kno its only MPP in germany producing dmm blanks right now. and quality is from great to whatever. so difficult.

Mm. And I suppose even if somebody could afford them and the shipping, unlike lacquer suppliers - they probably don't give credit for poor quality blanks.

2. to get a dmm lathe back to usa. i dont think that is possible. maybe easier and cheaper to go to one of those balancer stores of the CHURCH and ask for a membership.....

[LOL]

3. the speed problem is not a problem. the issue of 45 and 45.45 whatever in europe was only the case for lyrec motors. most professional studios in europe use technics motor or a vms80/82 where all is quartz locked.

Interesting.

4. good news about dmm styli. there is a new high quality source from germany so no problem there.

not to mention our buddy opcode66 in chicago - like to know how they're testing it out with no dmm in america....

what i heard was that this one was recently tested on a real dmm machine with blanks...with great results.

So I read on the other thread.

so let me know if you get the plans. i definitely can get it produced by prototype mechanics. we have them all around. and do all the winding and testing.

Perfect. We have it on pretty good authority that we're going to get an anonymous philanthropic grant sometime next year to do the limited-edition run of 16 RPM real-time-cutting DMM-mastered color-vinyl pressed of all the Seeburg BMS 1000 type background music discs produced from the 50s to the 80's - so like I said that'll serve as test material since there's like 100 titles produced per year times 30 years per publisher (meaning another hundred from Rowe and another hundred a year from CustoMusic and on and on)...and we figure onmaybe ramping up transfer and mastering production after NEXT Christmas i.e. around the first quarter of 2015. So that gives us roughly a year more to find all the head drawings and specs, get the rest of the grant money and do all the transfers for the Seeburg project.

i am not really fan of ortofon design. it might include expensive tools for the coil producing. but lets see the drawings first.

If we can even FIND em. That project in ITSELF is still ongoing.

We're still trying to find some of the retired Scandanavian engineers who worked on it back in the day to see if anything remains - although with a big company like ortofon - they SHOULD have something. but I guess we'll just have to keep researching and see what we get.

and also i wondering how the ortofon stylus holder looks like. this is a key issue. hopefully they used the same as neumann. but i dont think so.

No - it's different to be sure as is the tip style - but if we can get our hands on the designs - maybe we can petition for a second grant to pay our buddy over here to make us some Ortofon DMM cutting styli.

Do YOU know anybody over at Ortofon? or can you fish around from over there being you're at least on the same side of the planet as them?

Or - being opcode66 already making his own Neumann replacement styli - maybe HE can research the ortofon tips for the DMM heads they had six experimental versions of back in the 80's and see if THAT'S even worth pursuing or not.

Granted the whole Seeburg project was chosen for the specific purpose of being noncommercial (i.e. beyond the thousand sets produced to pay the guys back for lending us their discs - and selling the remainders online) - if we're LUCKY we break even on THAT project - but then we're going in EXPECTING that - so there won't be any rude shocks later.

And on a COMPLETELY different topic - we inherited a two speed (19/9.5 CPS) Tefifon Stereo Schallbandspieler - (KC-4Z) which we've never heard of either - only the KC-4 stereo 19CPS versions have we seen, so we're also vying with a couple other only-marginally-interested people - to transfer and restore all the Tefifon Schallband ever made - including the few stereo bands made in the early 60's before it went out - and including the half speed 9.5 CPS talking books for the blind produced on the format in Germany Switzerland and Czechoslovakia.

So we're gradually collecting Tefi schallbands until we have at least one good copy of every schallband ever produced - including the talking books if we can find any. And since there was blank schallband produced - if anybody ever heard of anybody recording on a Tefifon for their own home use - we'd like those as well just for ha-ha's.

And the Schaub-Lorenz 5CM and 10CM wide multitrack tape recorders that used to be inside of a 5001, 5005 or the 6000 stereo version - for the same reason - preservation of odd formats.

But the Schaub and Tefi projects are on the WAY back burner. Just to give you an idea where we're heading and what we expect to be able to do with the results of one experiment compared to funding the next few.

[TimDog73]

Hi Diamone,

We are working on a software based CD-4 demodulator project and wondered if you might be interested to help us out?

I have posted the topic here: https://www.lathetrolls.com/viewtopic.php?f=15&t=4523#p27711

I look forward to hear from you.

Kind regards,
Tim

[diamone]

We are working on a software based CD-4 demodulator project.

Two things:

http://www.plangentprocesses.com

1. You should see if http://en.wikipedia.org/wiki/Jamie_Howarth has time to give you his input - because he's using +/- the same frequency to recover from speed errors from when analog* tape was first recorded - using the bias tones impressed thereupon when the session tape was first recorded.

* Because the original bias tones don't get superimposed on the dubdown - the process only works on the original session tape though - if you try it on safety dubs and mixdowns and etc all it does is erase the most-recently applied speed errors from the most-recent dubdown.

You should check out the CD-4 threads on the QuadraphonicQuad forums being there's other design and fabrication engineers working on the same as you over there and maybe you could team up and/or avoid re-inventing the wheel by sharing ideas and pitfalls.

But I'd be happy to help you as a reviewer when it's all done being that's not my area of expertise.