Opinions wanted on a DIY turntable project

68.82.88.100

Posted on December 14, 2014 at 22:50:15

henrybasstardo
Audiophile

Posts: 1690
Joined: June 25, 2003

I am open to suggestions on my project.

My plan is to use the motor, platter and bearing that is pictured and make a turntable. I need to choose an arm and cart and have a $700 budget max.

I plan to use slate for a plinth. I talked to John from Oswald Mill about slate and some tricks and I will be slate shopping tomorrow.

The slate will be water jetted to accept the flat aluminum base that holds the platter bearing. The quality of the platter, bearing and the hysteresis motor is very good. I want to machine a groove on the outside of the platter and a pulley for a belt drive like Empire tables. I want to control the speed of the motor with a Falcon PSU.

I am overwhelmed with choices but I am leaning towards a vintage SME like a 3009. I can always add another better arm if the table proves to be quiet and functional.

The motor mounts and feet and such will be machined aluminum.

I appreciate any opinions so many of you guys really know your stuff. I do not know why I am building I think I like to torment myself. There is a lot to work out. Think it will work? Thats a good question? lol

Cheers

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Why not a DIY unipivot tonearm...

cactuscowboy@bresnan.net

14:18:59 12/16/14

RE: Why not a DIY unipivot tonearm...

henrybasstardo

21:18:10 12/19/14

Or a "String Theory" arm

CometCKO

06:32:58 12/20/14

...

Show full thread outline!

Why not a DIY unipivot tonearm...

cactuscowboy@bresnan.net

14:18:59 12/16/14

RE: Why not a DIY unipivot tonearm...

henrybasstardo

21:18:10 12/19/14

Or a "String Theory" arm

CometCKO

06:32:58 12/20/14

Experience is a hard school...

CometCKO

13:49:53 12/16/14

RE: Experience is a hard school...

henrybasstardo

21:16:24 12/19/14

Yes, I've been following the Phoenix project

CometCKO

06:25:07 12/20/14

seconded: go linear

troporobo

16:08:28 12/15/14

Good arm too!

Dman

05:49:18 12/16/14

3009 is poor for the money

richardl

12:35:40 12/15/14

RE: Finally!

amioutaline?

16:15:41 12/15/14

RE: 3009 is poor for the money

mosin

15:45:27 12/15/14

Or a Jelco arm

Cuernavaca

08:58:22 12/15/14

Can't go wrong with the SME...

Dman

05:53:19 12/15/14

Or a Souther

Paully

13:51:42 12/15/14

Can't go wrong with the SME..., posted on December 15, 2014 at 05:53:19

Dman
Audiophile

Posts: 7211
Location: Kansas
Joined: January 28, 2001

But have you thought of a linear tracker, like the Advanced Analog MG-1? Not sure if this is your cup o' tea, but having heard it, I can say it is awfully good!

I'm not a seller, selling or a dealer for this arm, just a listener who still hasn't been able to come up with a measly $600...

Cheers,
Dman
Analog Junkie

MG-1

Or a Jelco arm, posted on December 15, 2014 at 08:58:22
Cuernavaca Audiophile Posts: 878 Location: NW Joined: December 23, 2011	The cost of an SME 3009 arm has increased so much the last few years, I would choose a Jelco 750 or SA-250, to my ears performance is better with a Jelco. I'm sure opinions may vary... TR "I've never owned a firearm, but I do have an attack parrot!"

3009 is poor for the money, posted on December 15, 2014 at 12:35:40
richardl Audiophile Posts: 3555 Joined: September 5, 2002	It is rolled off on both ends and is not comparable to modern arms that simply outclass it at the same price. With spending on a slate plinth, I would be going for a better arm for bass and treble IMO.

Or a Souther, posted on December 15, 2014 at 13:51:42
Paully Audiophile Posts: 5909 Location: West Virginia Joined: February 15, 2004	One can be had under his max price. I am very fond of mine.

RE: 3009 is poor for the money, posted on December 15, 2014 at 15:45:27
mosin Manufacturer Posts: 10719 Joined: July 24, 2003	I agree. It works very well with an Shure V15III, and that's about it...probably a few other MM cartridges. By the way, I own one, but I keep it more for sentimental reasons than anything else.

seconded: go linear , posted on December 15, 2014 at 16:08:28
troporobo Audiophile Posts: 1648 Location: Manila Joined: June 6, 2003	I put an Eminent Technology ET-2 on my project table. Glad I did too!

RE: Finally!, posted on December 15, 2014 at 16:15:41
amioutaline?	Someone with the intelligence to agree with me. The III is no bargain, either.

Good arm too!, posted on December 16, 2014 at 05:49:18
Dman Audiophile Posts: 7211 Location: Kansas Joined: January 28, 2001	I can't wait to go Linear on a Linn (or rather my very good DIY version)... Dman Analog Junkie

Experience is a hard school..., posted on December 16, 2014 at 13:49:53

CometCKO
Audiophile

Posts: 873
Joined: August 9, 2002

I'm pretty far down a similar path. In my case, I started with the Empire/Rek-O-Kut Papst motor and the bearing/platter from an Empire. Before you get very far along, you should make sure your motor is up-to-spec. On my motor, I could replace the thrust bearing with a new Delrin disk and that made it much smoother and quieter. The Falcon wthetheill let you control the speed by varying the frequency and let you reduce the voltage a bit which often helps vibration (does not actually help with my Papst). It also gives you the option/opportunity to buy the module to speed-monitor and feedback to slowly adjust to keep long-term speed close to spec. But if your chosen motor itself is not quiet, everything else about your design will be compromised. Ask me how I know this....

I'm now on my second motor!

You also need to think about whether the motor is a stand alone SAMA or whether it is mounted somehow in the plinth. I had some conversations with Harry W at VPI who is an Empire enthusiast. He convinced me of the benefits of having the motor quite close to the platter, as was done in the original Empire design. I duplicated that layout on mine, which resulted in a lot of trial & error machining a pocket for the motor of the right size beneath the plinth. It also involved looking a how to suspend it in such a way that vibration would not be transmitted to the plinth. i found a company that makes good suspension/isolation bushings which seem to do the trick for me.

I've also worked through quite a variety of platter and mat designs. But that is another story unto itself. I certainly like a damped aluminum platter better than the acrylic platters I've worked with in some other attempts.

Slate as a plinth material has its pros & cons. I considered it for mine, but ended up with a 3-layer high-mass base, with a 1"thick aluminum plate clamping a sheet of EAR Isodamp to a steel layer of identical mass (about 3/8" thick) which is glued to a damping base of 2.25" MDF). It ends up at about 75 pounds. It is suspended by a frame made of 3" thick Walnut, anchored by 3 Terrastone/brass footers equidistantly spaced around the center of mass. I consider the plinth a little livelier than the slate one I used on my Thorens TD124 project, but still quite quiet. No ringing at all, since the aluminum and steel resonate at different frequencies and are clamped via a superior constrained damping layer, further damped by the MDF.

As far as tonearm choice goes, you might want to think about through-arm mounting vs. Surface mount early in the process. I went the SME mount route, which means that whatever arm I choose has to work with the SME standard. But that also means there's a BFH (Big Frickin' Hole) in my baseplate. I originally fitted an SME 3009-II, but as others here have noted, it is not the last word in performance, especially in the bass. I borrowed an SME 309 and liked it fairly well, but before I bought one of my own, I discovered a cottage manufacturer in the UK who was spinning off the SME design and making his own tonearm with the goofy name: Sonik Sircle. I saw a positive writeup of the arm in a Brit Hi-Fi mag and started a correspondence with the designer. He's an expert on resonance and vibration. He makes a replacement wand for the SME which is damped carbon fiber and for less than $700 I had a really nice-sounding arm that thoroughly thrashed the SME 309, at least on my table. I think I would need to go to at least an SME-V if not a Graham Phantom SME-mount to better its performance.

Anyway, hopefully this will help you, or at least give you some things to think about. I do have full pics of my build process if you want to PM me. Good luck with your project and keep us posted on your progress!

"Knowing what you don't know is, in a sense, omniscience"

Why not a DIY unipivot tonearm..., posted on December 16, 2014 at 14:18:59
cactuscowboy@bresnan.net Audiophile Posts: 7738 Location: Powell, Wyoming Joined: July 23, 2007	My project from a few years ago incorporated a direct drive motor & platter. I designed and built a wooden unipivot tonearm. Parts cost for the tonearm was well under $50, and that included a jewel quality sapphire bearing with matching stainless steel pivot and Cardas tonearm wire.

RE: Experience is a hard school..., posted on December 19, 2014 at 21:16:24
henrybasstardo Audiophile Posts: 1690 Joined: June 25, 2003	Thanks for the post. I have a lot to think about for sure. Your post will surely help. One thing I did find was my motor is too big for the Falcon but the company is coming out with the Eagle that will work for it. I will be back at this after the new year. Happy Holidays to you and yours.

RE: Why not a DIY unipivot tonearm..., posted on December 19, 2014 at 21:18:10
henrybasstardo Audiophile Posts: 1690 Joined: June 25, 2003	Now that is cool!! I will look up the posts for that project. It looks awesome Thanks!

Yes, I've been following the Phoenix project, posted on December 20, 2014 at 06:25:07

CometCKO
Audiophile

Posts: 873
Joined: August 9, 2002

I'm a big fan of Phoenix Engineering's project. In fact, I was the one who jokingly suggested the name "Eagle" ;) It seems to have taken hold.

My Papst motor pulley is slightly large (or the circumference of the platter is slightly small) so my table runs slightly fast, based on a couple of downloaded smartphone apps for measuring speed. Interestingly, the thickness/width of different belts changes the measured speed significantly in this design (using a double-tapered motor pulley).

My VPI is dead-on 33.3rpm, but the DIY table runs at 34.1rpm. The speed problem is much easier to fix by varying incoming frequency, compared to machining the pulley. That's not to mention the Phoenix advantage of regenerated AC voltage as it improves stability and lack of noise.

I'm looking forward to the higher-power version. What I really *should* do is build a proper 3-phase supply that feeds each of the coils on my motor (it's a 3 phase synchronous eddy-current motor). But the feedback mechanism that Phoenix has developed looks like a superior solution.

Another factor from a motor noise standpoint is the voltage. I've found through experimentation that the Papst actually runs smoother/quieter at faster speeds. Using the Phoenix, I might be better off putting the belt on the 45rpm pulley and using the controller to drop the frequency so I can obtain 33.3rpm at the platter with a higher motor speed. The Papst seems unusual in this. Other motors I've used (Thorens) seem to be quieter with lower voltage. But it is (yet) another thing to focus on.

When designing my table, I broke it down into four areas and worked through each one. So I did development testing on motor mounting and motor noise. I worked on plinth design/layers/damping. I worked on the platter, which needed damping (rang like a bell!). And I worked on alternative tonearms. All told, it took me about a year to arrive at the final table, much of which was spent waiting to get parts out of the machine shop.

Fortunately, I'm very happy with the outcome. One of these days, I'll put my pics together and tell the story here. It was a very rewarding job!

Good luck with your project!

"Knowing what you don't know is, in a sense, omniscience"

Or a "String Theory" arm, posted on December 20, 2014 at 06:32:58
CometCKO Audiophile Posts: 873 Joined: August 9, 2002	Check out Pete Riggle's well-engineered DIY arm. I think he used to sell kits as well as VTA risers for SME-mount arms. But I have a friend with the Pete Riggle arm and it sounds very impressive. Worth checking out just to see how he did it. He advertises in the Audio Asylum classifieds. HTH, "Knowing what you don't know is, in a sense, omniscience"

Vinyl Asylum

Opinions wanted on a DIY turntable project

68.82.88.100