TT Motor Controller

GGA · « **Reply #40 on:** 3 Jun 2009, 12:55 am »

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At the moment, trying to imagine all of the interactions / impedance / EMF etc. between motor, tranny, wiring, and amplifier.

Wouldn't it best to design the controller for a specific modified motor, which you would also sell? This might also simplify your design? It seems critical to remove the caps in an AC motor for best results. The Walker retails for $1500 but is still limited by the caps in the motor.

Perhaps you could also offer a second "universal" verson for those who wish to keep their motor.

bigfishe · « **Reply #41 on:** 9 Jun 2009, 12:35 am »

I love my Oracle as much as my Cuss t em Sparta broadcast aaTT

SoundBound · « **Reply #42 on:** 26 Jun 2009, 09:02 pm »

Has anybody heard of or seen any DIY turntable projects that make use of old reel-to-reel motors?

I have come across an old Sony reel-to-reel, that is not not working, all the rubber idler wheels are worn and useless and it's not a great unit anyway. Well, it has an excellent AC motor which is very powerful and quiet too. I thought this might make a great motor for a DIY turntable, belt driven.

It would need speed regulation and I am hoping that this TT controller project would be just the ticket. It looks like a multiphase AC motor as there are 3 wires going to it and there is a capacitor associated with it (phase delay?) .

If anyone has any experience with this or heard of any projects using this, I would be curious to find out. If it's feasible I would salvage the motor in hopes of being able to use it when Jim reveals his controller to the world.

Motor is a 100 VAC 50/60 Hz

tubesforever · « **Reply #43 on:** 27 Jun 2009, 05:54 am »

It might be dangerous to simply speculate here, but generally speaking the motor will have how many wires equal to how many windings. So a single phase motor will have two wires, a three phase motor will have three wires and a two phase motor would have 4 wires.

But what about a motor that has two motor winding wires and an internal ground connect. Now you have three wires but still have a single phase motor.

The owners manual is likely to state in the specifications what type motor they are running.

Do some more research and let us know. BTW what does the motor inspection plate say? It will generally say everything a tech needs to know to test it for proper functionality.

Cheers!

Cheers!

Tone Deaf · « **Reply #44 on:** 24 Jul 2009, 07:25 pm »

Hi Jim, have you had any further thoughts on this proj development?
TD

hagtech · « **Reply #45 on:** 2 Aug 2009, 04:32 am »

I'm sorry to report no progress. Day job is kicking my butt. I'm not finding the time to spend on this design. No small project, either. I was hoping to have proto by RMAF, but that ain't gonna happen.

I do have a small project in the works. Not for TTs, though. Sure was a lot easier getting the R&D done when Hagtech was my only job.

jh

tubesforever · « **Reply #46 on:** 2 Aug 2009, 06:31 am »

Amen Jim......

I have five projects in the works and where I might be able to get all five done in a month with no career, I will be lucky to have all five done by the end of September or even early October....

Who the hell said a motor controller would be easy?

Building high level motor controls is an art as much as a science.

Cheers!

Demsy · « **Reply #47 on:** 4 Aug 2009, 03:45 am »

Jim, just an input to your TT project.
I use the Michell QC Power Supply, all pretty staright forward. Uses bi-color LED, green for 33-1/3 and turns red for 45 rpm.
There is one guy here in Jakarta that build and sell a controlled frequency power supply. It actually rectifies the AC supply and with an oscilator it then generates the correct frequency for 33-1/3 & 45 RPM. It has 2 selector switches, one for the frequency and the other is for voltage/frequency choice (220v/50Hz & 110v/60Hz). It is able to supply up to 11 watts, which is more than enough as in average t/t motors consume about 6 watts. Some people uses this thing for their phono preamps and claim it brings improvements.

hagtech · « **Reply #48 on:** 12 Aug 2009, 05:50 am »

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Some people uses this thing for their phono preamps and claim it brings improvements.

Yes, I would agree. A clean supply can often help. It would be perfect for small solid state phono preamps.

jh

hagtech · « **Reply #49 on:** 22 Aug 2009, 02:37 am »

Ok, I'm back on it. Trying to simplify the concept. Looking at transformers - the one I like is $50! Need two, one for input, one for output. Also goint to make first version a single-phase only. Just plug and play with most turntables. It will give me the technology base I need to go after 3-phase (which is too small a market to pay for the R&D).

I don't like the step-up tranny concept. Planning to make a full-voltage power amplifier for output stage, then coupled to load via 1:1 tranny. The cheap trannys have too much winding resistance. I want to run this open-loop, no negative feedback. That should make it play nice with most loads. Hence, the need for the expensive tranny.

Picked out the CPU. Going with the PIC16F688. I works with other projects I have in mind too.

Price, I'm a little worried about. $100 in just iron. Box and circuit board and other parts will bring it to $200 to $250. That could make it a retail price of a grand. More than I was thinking. Doesn't give me much competitive advantage.

jh

tubesforever · « **Reply #50 on:** 22 Aug 2009, 07:42 am »

I think the VPI SDS controller is a single phase and 950 dollars or somewhere around that.

A three phase motor control is what, the equivalent of 3 x 50 watt amplifiers..... Not a cheap proposition and you have to deal with the timing issues.

I did not expect to buy a kit cheap. I figured a decent 3 phase power supply would cost at least 500 to 600 dollars as a kit.

Cheers!

fatty · « **Reply #51 on:** 23 Aug 2009, 04:41 pm »

Jim,

Don't think you will sell that many unless the price comes in less than $500.00 for the kit.

mike1964 · « **Reply #52 on:** 23 Aug 2009, 04:58 pm »

Quote from: SCompRacer on 5 Mar 2009, 09:57 pm

The speed was near dead on with the Spacedeck, but near .3% fast with the 294, so I picked up a demo Wave Mechanic. Controllers sure can be pricey, so it will be interesting to see what Jim comes up with.

Very interesting thread. I use a Wave Mechanic with my Rega P25, as I happen to be very sensitive to pitch (quite an expensive affliction as far as music listening goes) and the Rega was very annoying to me w/o the controller.

The Wave Mechanic is a good target, Jim, as retail is ~$1600. The Walker is supposed to be very good as well. I'm actually soon getting a new 'table which has a DC motor, so won't need the Wave Mechanic any longer, so will be up for sale.

Galibier_Numero_Un · « **Reply #53 on:** 23 Aug 2009, 05:35 pm »

Hi Jim,

We're best of buds, and far be it from me to to tell you where your business model lies, but to my way of thinking, if you don't put the best there is in your crossshairs, you're wasting your time.

To my way of thinking, you make the best controller you can, and then strip away features for a budget model. Heck! Intel has successfully been doing this with their processors for as long as I can remember.

That's just me

Cheers,
Thom

PatOMalley · « **Reply #54 on:** 23 Aug 2009, 11:57 pm »

competitive advantage. <= Sometimes increasing your price for a finished product puts you IN the competition.

bigfishe · « **Reply #55 on:** 24 Aug 2009, 03:07 am »

Im with Thom on that one!!

Galibier_Numero_Un · « **Reply #56 on:** 24 Aug 2009, 02:12 pm »

Hi Pat,

I'm not sure I understand you, but if you're equating increased price with "perception of quality", well there are all too many incompetents and charlatans out there who are building and selling exactly this sort of product.

There are audiophiles who are unfortunate enough to buy into this, due to a combination of inexperience, listening to clueless reviewers, and frequently having too much money burning a hole in their pockets. I'm not as concerned with the fellow looking to throw $$$ at his solution as I am the poor working stiff with 3 kids and a mortgage.

If you drop down one level on the price scale, the world doesn't need another SDS controller. It's my contention that there are enough "me too" products out there, such that Jim will sell too few of this sort of product to make it worth his development time - even if he applies some innovative concepts - at least if he starts off with this sort of product.

Jim has the smarts to design something first rate, and this is how he can thrive in the audio biz. He can then apply his not inconsiderable smarts to leverage this development into a design that the poor working stiff can afford

I think this is the only way he can rightfully claim some of the market in the affordable class of components.

That's my story, and I'm sticking to it

Cheers,
Thom

PatOMalley · « **Reply #57 on:** 24 Aug 2009, 04:10 pm »

Thom,

I largely agree. I even have three kids and a mortgage!
All I was saying is that yeah the kits can stay online for us but the finished shrink wrapped job can go for a 'competitive' price. Which it rightfully should being that I think Hagerman's stuff is as good as stuff 3x his prices.

An empty board is only going to go to the DIY guys, who else? The finsished product should command at least as much as machines that are it's peers, not to mention inferior.

I am not sure if this is the right place to mention this but I am sure Jim is watching so here goes. The cut chassis are longer available from JH because he took a loss on them. I think he should charge enough to make a profit on them and make them available again. I had to run around like crazy to get mine cut, too long a story. I would have happily paid more for one from JH being that it would have the silkscreen.

I would buy another Cornet2 as well but I do not want to go through the chassis thing again so I may go to another kit just because of that one thing.

How many other DIYers are put off by having to deal with the chassis?

fatty · « **Reply #58 on:** 24 Aug 2009, 07:33 pm »

I think that there are more than one way to skin a cat----ie., for example--the Cinemag transformers are 300 % cheaper than Jensen trannys and 500 % cheaper than some of the "hand wound,custom built with exoitic wire" trannys but Cinemag has always built a quality product. There examples of this in every category of audiophile products. I personally hope that Jim comes up with a controller that is affordable---by this I mean a DYI product that comes in at under $500. If it is the $800 to $1000 range--I will not buy it !

analog97 · « **Reply #59 on:** 24 Aug 2009, 09:38 pm »

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How many other DIYers are put off by having to deal with the chassis?

I am in that camp. If it weren't for Jim's offering of the "factory" chassis, I might not have my Cornet2 and Clarinet. I now have a couple step-drills, just in case I need to try them out on a new kit. Basically, I have a "perfect" factory C2 and Clarinet and a shitty-looking-but-great-sounding PICCOLO that I botched the casework on....darn....gotta fix that, but it will still look "home-made"....