View Full Version : Direct drive unit ideas please
Hi All,
I have been out of tough with the Hi-Fi forums of late, mainly due to a depressing lack of funds & employment!
Thing have turned around now, and I have the urge to upgrade....
Below is my current DIY TT, using a DC motor, VPI scout platter & bearing, home made CLD plinth, Rewired SME3, AT33PTG and CA640P.
http://i732.photobucket.com/albums/ww322/evozero7/DIY%20TT/DIYTurntable007resized.jpg
http://i732.photobucket.com/albums/ww322/evozero7/DIY%20TT/P10409282resized.jpg
I am very happy with the sound of the deck, but it has one really annoying problem, speed drift.
It's effected by temperature, and friction, belt tension etc. Normally i just use the KAB strobe before a session and it runs fine, but the next day it will be out again.
So I was think of going direct drive and would like some suggestions on what route to take.
I have seen standalone drive units like JVC, Denon, Technics etc but they appear to hold their value, would a SL1200 motor unit be a good idea for re plinth, I hope to reuse the Walnut, rubber, granite again.
Thanks
Ian
A battered but functional SL12XX would probably be an ideal donor, I would have thought. Housing all the 'gubbins' that go along with the motor could be an issue though...
I agree with the SL route, especially as there is an upgrade path regarding the PSU and bearing.
But the ease of a self contained drive unit is also very appealing.
All ideas gratefully received.
Cheers
Ian
Nice looking tt shame about the speed drift
The other option is get the sds fot the VPI motor its quite a big upgradde and while quite ostly by the time you get the 120 up to the same standards may well be the better bargin
Just my view having owned a Superscout Master Also it you really want to go to towm get the heavy platter that should sort out the speed issues
I know its not what you were asking but well worth considering.
The even better option would be slightly redisgn the plinth put a heavy platter on and get a Teres Verus drive now that will boggie Expensive but very serious performance
The Vinyl Adventure
26-08-2010, 17:25
the difficuly you will have i would have thought, would be cutting the right shape out of wood and the minimal amount of screws affixing the parts of the techie into wood without jepodising function.
where the main board (contating the motor) is affixed to the plinth and the bearing would be a point of issie... firstly the position of the three long screw would be close to the edge of the cut of wood. also you would have to get the mounting holes it dead vertically true ... i have no idea how hard that would be
this is a picture of a stipped down to basics 1210 under the hood
http://i728.photobucket.com/albums/ww282/hamish_gill/P1010504.jpg
the bearing is recessed into the centre and 3 screws go through the motor, through the bearing and into the plinth... it might be doable, but this bit would b the hardest...
this is under the main board next to one with one in place
http://i728.photobucket.com/albums/ww282/hamish_gill/P1010505.jpg
you can see the 3 holes right at the edge of the indent for the bearing
also if you succeed i might make you make me one too .. just so you know :)
The Vinyl Adventure
26-08-2010, 17:29
another point in its favour this time... the pitch fader and stylus light can easily be diabled and removed and the buttons could be mounted in a separate box... in fact i have a chap making me such a box so i can ea over the holes and have a flat topped top bit
Don't forget about mounting the switches, strobe, pitch control etc.
Could the extra 'gubbins' be mounted in an external box to keep the actual deck clean and uncluttered, I wonder? :scratch:
The Vinyl Adventure
26-08-2010, 17:32
Don't forget about mounting the switches, strobe, pitch control etc.
Could the extra 'gubbins' be mounted in an external box to keep the actual deck clean and uncluttered, I wonder? :scratch:
yes eassily.. most of the gubbins as i said can be got shot of
The Vinyl Adventure
26-08-2010, 17:33
sory if my posting is even more barly litereate today i have a corkin head ache
sory if my posting is even more barly litereate today i have a corkin head ache
I'm working on one for tomorrow! :cool: :eek:
Reid Malenfant
26-08-2010, 17:39
Hamish, can i ask a question here? It looks to me as though part of the motor is attached to the platter, is this the case?
As i say, this is how it looks to me :scratch:
If that is the case there may well be better direct drive motor system that could be used as there will also be big problems getting the part that looks like it's attached to the Technics platter to be in presice alignment on the arcylic platter of Ians turntable :rolleyes:
An Aiwa AP2600 has the direct drive motor all of a piece, when the platter is removed (heavy git that it is) the motor is completely seperate ;)
The Vinyl Adventure
26-08-2010, 18:01
the magnet for the motor is part of the platter yes, but thats it... i doubt it would cause an issue really
Hi All,
Hamish, thank for the photos and info, it does make for a reality check and how difficult the task may be. But if it works out i'll build you one ;)
What is the plinth made of? The reason I ask, would it be possible to cut round the circular part of the plinth, to contain the mounting points of the drive system / bearing?
I guess another option would be asking an engineer to make a mounting plate with the screw holes accurately set and mount this on / in any plinth you like?
Or use a self contained drive unit as mark suggests, what would be the choices here?
Thanks
Ian
This guy made a very nice job here:
http://theartofsound.net/forum/showpost.php?p=31745&postcount=28
Giovanni, that is a great link.
The guy done good, and has the tools / skills for the job.
Cheers
The Vinyl Adventure
27-08-2010, 11:46
Indeed, I thought I had seen that somewhere but had pretty much convinced my self it was a dream as I couldn't find it ...
One thing to bare in mind is that one of the major upgrades is the baring, you would want to make sure that the centre hole, however you make it/have it made is big enough for the larger better bearing not just the techie one... But that wouldn't be to hard as long as you modle the hole directly on the techie one!
I thought myself a lot about rebuilding the plinth of the SL 1200, mainly because I would like to install a 12'' tonearm.
Well, my naive idea is to build a wooden plinth taking the place of the lower rubber of the stock SL 1200 and then placing the upper alu section (along with electronics, platter and so on) on or inside it. In other words I'm not going to change anything of the original electronics and mechanics.
The final effect should be, let's say, the same of the Lenco L 75.
Some good ideas here, but i think for me its a case of either modifying a SL12, fitting my SME, time step etc and keeping the standard plinth or fitting a motor unit to my existing plinth and arm.
Does anyone have something like a JVC in the loft they can sell me cheap please?
Cheers
Ian
Hi Ian,
How are you? I hope all is well :)
Just a quick one... Could you add your basic geographic location details to your profile, as this is now part of the membership requirements for AoS.
Cheers, buddy! :cool:
Marco.
Reid Malenfant
01-09-2010, 13:10
Does anyone have something like a JVC in the loft they can sell me cheap please?
Cheers
Ian
Hi Ian, are you after a quartz locked direct drive TT?
Hi Marco,
I am well thank you, Just getting back into the AOS again, I love it, but it always costs me money!
I have some paid work at last, so taking the chance to sort a few issues out while i can.
Like finding a motor unit for my TT. I need to update the forum on my open baffle, H frame speakers, Ill get the camera out....
Mark, I am looking for a quality DD motor unit, but will take advice on quartz locked etc.
I thought JVC units were good and came up cheap every now and then?
All the best
Ian
Hi Ian,
Thanks for that. Good to hear that things are on the up :)
Enjoy the forum and get stuck in - I look forward to hearing all about your latest projects (with pics) :cool:
Marco.
Reid Malenfant
01-09-2010, 13:42
Mark, I am looking for a quality DD motor unit, but will take advice on quartz locked etc.
I thought JVC units were good and came up cheap every now and then?
All the best
Ian
Yeah, that's what i thought ;)
I happen to have a couple of JVC turntables both of which are quartz locked direct drive just like the Technics 1200/10. One i'm not sure about selling as it's a rather expensive bit of kit with an all electronic pickup arm etc etc. Model number would be QLY5F if i remember right.
However i do have another that i can't remember the model number of :doh: This has variable speed similar to a Technics & is quartz locked & direct drive etc. I'd be willing to part with it for a reasonable sum (read cheap) ;)
If you are interested i'll dig it out & check it all works properly (no cartridge) & you can either make me an offer or i'll chuck in a suggestion :)
Mike_New
02-09-2010, 08:00
Hi Evozero,
I have not been keeping absolutely up to date with the various posts re SL1200s and what people would like to do with them. I have I believe what you could be looking for however. I have, over the last 6 weeks, been working with a number of people mainly in the US, on my rather radical upgrade to the Sl1200. this is the 'Bearing Base Plate', which greatly increases the rigidity of the SL1200 chassis.
The point is, for your requirements it is a large 125mm diameter 6mm thick plate Laser cut from milled-plate-steel. It is equiped with five 5mm fixing holes and is designed to clamp to my bearing with three 4mm tensile bolts.
You could use this to transplant the motor/coil/PCB assembly into you own plinth if you wish.
Hi Mike,
How's it going? I hope all is well! :)
I have, over the last 6 weeks, been working with a number of people mainly in the US, on my rather radical upgrade to the Sl1200. this is the 'Bearing Base Plate', which greatly increases the rigidity of the SL1200 chassis.
Sounds intriguing! Don't ignore us on this side of the pond, as we're just as interested in these things as your American friends ;)
So tell us more about the Bearing Base Plate - exactly what it does, what sonic improvements you perceive with it fitted, and cost and availability to folks in the UK.
AOS is the home of 'serious' SL-1200/1210 enthusiasts/modifiers, so please always keep us informed of your new products :cool:
Marco.
Mike_New
02-09-2010, 12:00
Marco,
Whats this about the other side of the pond!! I am at the bottom of it in OZ!!!
I have posted a short resume' of the new Base Plate upgrade, under the title of Base Plate upgrade, I have been reluctant to do so before until I had resolved all the installation issues.
I guess it was 'Evozero's enquiry about transplating a SL1200 DD system that prompted me to respond to his request for help.
Hi Mike,
LOL... Thanks for the update. I've just had a quick look at the other thread - sounds very interesting!
I've made it into a 'Sticky' thread, as I think this is a significant refinement to your (already excellent) platter upgrade.
I'll comment more there later :)
Marco.
P.S I've moved the Bearing Base Plate thread into the trade area, as I feel that's where it is best represented. Members are welcome to ask any questions they may have there :cool:
Mike_New
02-09-2010, 12:29
Marco,
Thanks for you support
dale kid
02-09-2010, 18:47
Well the Golden Oldie sticks nose in once again as (to my mind at least) the amusement continues regarding modifications for "that" turntable!
If I may be permitted to rumage through my thoughts (born of distant memories and experience) about the item under discussion in this post and mull over some of the statements made (no offence intended by the way and I do hope none will be taken!).
If anyone feels my thoughts should not be posted here would the forum admin please move to a more appropriate section (or new thread).
First thought goes to the statement about the chassis being "very thin metal" and having "little real positive mechanical support"
Hmmm, methinks would it be possible to take the metal casting and place this at ground level with some on supports at both short ends and allow a person of average weight to stand on the casting? Deformation? Instant collapse of very thin metal?
Second thought goes to the statement about CAD analysis showing that with a new heavy platter the "chassis not doing justice"
Well I would have thought the obvious here. The chassis forms part of the production design concept with the specification optimised for the most effective performance as part of the complete chassis/platter/bearing interface.
Introducing a heavy platter into the equation is the antithesis of the original design parameters with the chassis now stressed beyond design limits. Chassis resonance control and structal integrity now out of the window so to speak!
Surely no surprise then that it is now necessary to apply a" band-aid" to fix this introduced chassis resonance/structal integrity problem and so on ad infinitum with the next fix.
Third and final thought goes to the statement about using a substantially heavier platter than was "envisaged by the designers of the sl1200"
Please see my previous rambling on the subject of motor design with particular reference to the point about the introduction of a heavier platter only into the motor loop not allowing or ever allowing for optimum performance with this motor design.
To the contary the original design team did indeed envisage and test many platters of differing weights and moments of inertia (please see my previous rambling on the subject). Using a heavier platter in the final design was dismissed as an option as better performance was more easily obtained with a lower platter weight and a corresponding increase in the number of motor
poles.
May your days be long and peaceful, Dale
Hi Dale,
Thanks for your erudite views on this matter, which are obviously born from considerable experience.
Constructive criticism of products is always welcome on any level, but normally such discussions are reserved for other areas of the forum.
However, on this occasion I'll leave it up to Mike whether he thinks that this discussion is best served here or on a separate thread in the Analogue Art section of the forum. If it's the latter, then I will move it later.
Incidentally, when you say:
To the contary the original design team did indeed envisage and test many platters of differing weights and moments of inertia (please see my previous rambling on the subject). Using a heavier platter in the final design was dismissed as an option as better performance was more easily obtained with a lower platter weight and a corresponding increase in the number of motor
poles.
...is this 'inside knowledge' (i.e. did you used to work for Matsushita Electric), or if not, where did you obtain that information? :)
Marco.
Reid Malenfant
02-09-2010, 20:09
...is this 'inside knowledge' (i.e. did you used to work for Matsushita Electric), or if not, where did you obtain that information? :)
Marco.
This might be slightly out of the ordinary, but Hornby locomotive models generally used 3 pole motors in their models. Much better & vastly smoother performance of the engines could be had by increasing the motor poles. Going to 5 or more resulted in a much smoother start & run in general.
I learnt this when i was less than 16 ;) I'd suggest it has nothing to do with insider knowledge & more to do with sensible design :) You'll get more & closer together pulses feeding the platter in the case of the 1200/10 which will result in smoother running & less need for a high mass platter to give flywheel effect.
Just imo of course...
E2A:- think of it like a car engine :eyebrows: A V8 is much smoother than 4 cylinder inline.
dale kid
02-09-2010, 20:56
Marco, my past sins include an association with Matsushita in the very early 1970's and in less distant years with what is now known as PEDE (Panasonic Electronic Devices Europe).
All the original Osaka design teams have long become a relatively distant memory. The shift away from the original Matsushita design team heritage and the eventual close down of the brand was spread over some years.
Even so a model of turntable from a certain Osaka plant continues to be produced in sporadic batches. The question remains, for how much longer?
dale kid
02-09-2010, 21:04
Mark (Reid Malenfant), it can be said motors are often designed to achieve maximum torque at higher rotational speeds and that faster motors can be made smaller with fewer poles.
Conversely turntable motors are more often designed to run at slower speeds and therefore need to be physically larger. With certain designs of direct drive motor the flywheel effect is not really an issue.
Of much more importance is the ability to precisely control rotational speed. Small voltage variations on a high speed motor can often be ignored or be unoticeable. Again conversely in a direct drive motor small voltage variations will directly affect rotational speed and be highly noticeable.
Hi Dale,
Marco, my past sins include an association with Matsushita in the very early 1970's and in less distant years with what is now known as PEDE (Panasonic Electronic Devices Europe).
Ah, I suspected from the way you wrote that you had some form of involvement with Matsushita :)
So that's what the company is called now, PEDE...... I didn't know that.
All the original Osaka design teams have long become a relatively distant memory. The shift away from the original Matsushita design team heritage and the eventual close down of the brand was spread over some years.
That's interesting... Any other snippets of historical info would be gratefully received, as I (and I suspect others, too) are very interested in this whole subject.
Even so a model of turntable from a certain Osaka plant continues to be produced in sporadic batches. The question remains, for how much longer?
I presume you're referring to the SL-1200/1210 - if so, why "sporadic" (I thought they were still selling like hotcakes to the DJ fraternity)? Are you saying that there are plans to stop production?
I've heard this rumour before but didn't really afford it much credence.
Marco.
dale kid
03-09-2010, 08:12
Mike New, oh dear! Never my intention that my thoughts would provide a source for such rumbles! Before I return to the comfort of my armchair and slippers I would like to make a comment that the thoughts (ramblingss?) I previously expressed were only intended as a non offensive rebuttal for some of the negative comments expressed in the first post.
Perhaps some cynicism (self directed and none directed such as you have done in reply) but please read again and nary a reason for saying it cannot be done. Perchance those managers in the past may have been trying to tell you something?
Read my thoughts with more care and perhaps you may see my intention is not to dismiss willy nilly but to provide a defence of the original concept (which has worked rather well over 34 years or so and some three million plus sold) and offer an alternate opinion that the nature of these so called upgrades does not always provide the instant nirvana we all seek by means of tweaking and tuning. As you have discovered and appear to be learning by trial and error as you go along there is more to it than first appears.
Kudos to the attempt you make but there is a rapidly approached limit as to how far you can go without upsetting the whole design concept (god forbid that we should stop to consider the fundamental design principles in this case before we even start the attempt).
Perhaps controversial but my own opinion is that I feel there is a sad lack of real experience and true understanding of the design principles being shown by some concerning the application of upgrades to the turntable in question. But we live in an open society and people are free to spend their money as they feel fit, never mind the old adage , something to do with "easily parted".
Hi again everyone,
I am really enjoying all the input and banter, all very interesting reading.
Mike, would you mind hinting at approximate costs, it does sound like a well engineered solution, my only reservations are adding up the costs of the SL route, used deck, bearing,psu, platter etc. I have no doubt it would sound fantastic, but a used motor unit or TT would probably work out a lot cheaper.
Can you guys suggest some good motor units or DD turntables to look out for, sleepers that can be bought cheap, I have been told to look out for JVC's but they don't come up often?
Cheers
Ian
I've understood that for many years now, the SL1200 series decks were made in "occasional batches" of a couple of week's production every year or so, the lines used for other things in the meantime. You may find that a very large number of SL12**'s can be made in a fortnight perhaps.........
topoxforddoc
06-09-2010, 20:17
Ian,
I've come in quite late into this. It looks like you're using tape rather than belt or linen thread for the drive from your DC motor. Some people swear by tape drive as it can be better than rubber belt or thread; however if the tension goes off, you'll get speed drift. Before you go into another major project, have you tried either a normal rubber belt or a piece of linen thread?
Best wishes,
Charlie
www.charlie-chan.co.uk
Spectral Morn
06-09-2010, 20:58
Ian,
I've come in quite late into this. It looks like you're using tape rather than belt or linen thread for the drive from your DC motor. Some people swear by tape drive as it can be better than rubber belt or thread; however if the tension goes off, you'll get speed drift. Before you go into another major project, have you tried either a normal rubber belt or a piece of linen thread?
Best wishes,
Charlie
www.charlie-chan.co.uk
Can you please pop into the Welcome section of the forum. Say hello to us, tell us about your system and the kind of music you like.
Regards D S D L
Mike_New
06-09-2010, 23:16
Ian,
To answer your question regarding prices of the various upgrades for the SL1200 go to the 'Trade Impressions" section and access the sticky thread Bearing Base Plate at the top.
Hi all,
Charlie, thanks for the advice, I have tried cotton thread. But i will try some surgical thread if i can find anywhere to buy some.
I do believe direct drive will have better stability, but sound better than my current setup, I don't know?
I have a "want to buy" ad here;
http://theartofsound.net/forum/showthread.php?t=7599
Just need you guys to dig around your attics and cupboards!
Cheers
StanleyB
09-09-2010, 11:03
Also look at braided fishing line. They don't expand and can land a 2 ton fish;).
topoxforddoc
09-09-2010, 21:46
Hi all,
Charlie, thanks for the advice, I have tried cotton thread. But i will try some surgical thread if i can find anywhere to buy some.
I do believe direct drive will have better stability, but sound better than my current setup, I don't know?
I have a "want to buy" ad here;
http://theartofsound.net/forum/showthread.php?t=7599
Just need you guys to dig around your attics and cupboards!
Cheers
Ian,
Having re-read your OP, does the speed just drift from day to day or actually whilst playing? If it's the former, that's a pain, but hardly the end of the world. If it's the latter, then that's a significant issue. If it is the latter, then it must be due either to fluctuations in your Battery/Controller DC supply, problems with your motor bushings etc or drive 'belt' tension. Usually it's the latter.
Best wishes,
Charlie
www.charlie-chan.co.uk
Hi All,
Charlie, thanks for your input. The speed drift has always been an issue, probably mostly due to my skills in perfecting a turntable. I have been successful with the plinth, arm and cart part, just keeping it spinning accurately. I think it could be a problem with any or all of your suggestions, but direct drive solves the puzzle and may even be an upgrade.
What really appeals is being able to forget speed instability on a daily basis.
I am not expecting this to be the best turntable in the world, just on a realistic budget.
Charlie, i have changed back to cotton thread after you suggested this. I think rumble has dropped from mag tape, but i still have to adjust the speed before each session.
While i am waiting for a DD solution to appear, i will persevere.
Cheers all
Ian
Have you thought about the Papst EDS1000 motor from a Dual 701 (also found in the Goldmund Studio)? This a very solid and robust piece of engineering with all it's electronics built in, so easy to incorporate into a home-built plinth, just needing a hole a little over four inches in diameter.
They come up on ebay quite frequently at reasonable prices, as here, in mint cndition with Shure V15 which puts this one right at the top of the price range http://cgi.ebay.co.uk/VINTAGE-DUAL-701-AUTO-TURNTABLE-SHURE-V15-3-MINT-ICON-/290468002937?pt=UK_AudioTVElectronics_HomeAudioHiF i_Turntables&hash=item43a13dfc79.
I have one built into a slate plinth, as here:
http://www.thepippin.plus.com/Fakedeck/DSCF0313.JPG
http://www.thepippin.plus.com/Fakedeck/DSCF0314.JPG
Sadly my DIY skill do not match yours!
All the electronics are built in, so you only need to make a housing for the mains transformer and arrange something a bit clever for the power and speed switching.
The turntable I removed this from was extremely battered and cost me about £35, but the motor is very robust and was in perfect condition. Good old German engineering...
Hi Shane,
Looks interesting, but i think might introduce the same problems of setup, like perfecting belt tension, temperature causing speed fluctuations.
Still looking out for a good DD unit.
Cheers
Ian
Not sure you got the point there, Evozero. This is a direct drive motor. It hadn't occurred to me before that it looks just like the sub-platter of a belt-drive TT! In essence, it is a cylinder about 4" in diameter and about 3" high, the top of which spins round all by itself! :)
Here is a pic of the motor with the rotor removed (courtesy of Vinylengine). If you look back at my first picture, you can see the three nuts and bolts through the mounting lugs shown here.
http://www.thepippin.plus.com/Fakedeck/Dual_701_Direct_Drive_Motor_Stator.jpg
and a cutaway of the whole motor/platter assembly. The platter just sits on top, needing a 16mm hole to fit over the spindle boss.
http://www.thepippin.plus.com/Fakedeck/701%281%29.JPG
PLEASE don't buy a classic deck to botch the motor out of. A standard 701 betters the standard Techie IMO and gives a fair measure of what's there on the vinyl and in the right proportion.
If you do decide to buy a 701 as a bitser (thanks Shane for the remains of yours ;)), the remaining parts should be easy to sell on, as so few get broken up.
http://i132.photobucket.com/albums/q8/DSJR_photos/DSCF0341.jpg
http://i132.photobucket.com/albums/q8/DSJR_photos/DSCF0414.jpg
I didn't realise that was a direct drive, looks cool.
But i still want to go for a high ish end Japanese unit. I feel the aesthetics of these would work with the plinth better.
Thanks for the ideas, please keep them coming.
Or should I just buy a whole new deck, I keep drooling over my keyboard when browsing the HiFi Do website.
Any recommended sources from these Japanese machines?
Cheers
Ian
I mentioned on the other thread regarding the technics SL120mk1 motor. It's like the Papst/Dual one, but maybe higher torque and with impeccable dynamic performance despite not being quartz locked (the torque is still high enough and it doesn't speed-hunt at all). A decent power supply is all it would need.
directdriver
04-07-2011, 16:42
evozero: "I didn't realise that was a direct drive, looks cool. But i still want to go for a high ish end Japanese unit. I feel the aesthetics of these would work with the plinth better."
You are missing out. I will say this: the Dual 701 motor is the best direct drive motor I have ever heard. It sounds better than anything by Technics to me. And I have owned many Technics turntables including SL1200Mk2, SL1300Mk2, SL1400Mk2, SL1500Mk2, SL150Mk2, SL1600Mk2, SL1700Mk2, SL1800Mk2, SP15, SP25, SP10Mk2. I sold them all and never look back. Let me just say Technics DD tables are simply not my cup of tea. I much prefer models from other Japanese brands such as JVC, Kenwood, Sony, Pioneer, Yamaha, Denon, etc.... and I have owned over 50 of them. I totally agree with Shane; the Dual motor is simply superb and placing that on a new plinth will surpass anything by Technics.
The Dual is "high-ish end" enough for me.
The Grand Wazoo
04-07-2011, 16:52
Hi,
It looks like you've been a member a while, but this is your first post!
Would you mind stopping by at the Welcome section & starting a new thread to introduce yourself to the fold please?
It'd be good if you could tell us a bit about yourself, your system & your taste in music. It is also now a requirement to display your real name either by filling it in your profile details (along with a basic location) or by showing it in your signature.
Thanks a lot and a belated welcome.
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