Pro-Ject Motor and SpeedBox with AR Turntables?

[MuZak]

Just butting in...

Hey grailer...
Butt in anytime!

Muzak, look for the yellow teflon tape - often referred to as gas line tape.

Great info!!! Thanks so much as usual!!
Now I can get the right stuff w/o further searching!!

[JXO]

A 16 pole motor will run fast than a 24 pole.16 pole motor at 60Hz 450rpm and a 24 pole motor 60Hz 300rpm.

For what it's worth, a quote from the US distributor when asked about the RPMs on the Pro-Ject motor:

"The motor does spin at 300 rpms and with a 60 hz pulley is what is used to regulate the Hz."

We shall see, this is the only spec that I am not certain of.

[JXO]

Here's an excerpt from a US review. The reviewer was using a Music Hall MMF-7 turntable. I do not know if that deck uses a 50 or 60 Hz pulley.

"The Speed Box II is said to control the frequency of the AC power being fed to the motor to within +/- .001 %. The included wall-wart powers the Speed Box, resulting in a cleaned up and stabilized output for the box to power the turntable motor. To use the Speed Box, the belt is placed on the larger 45-RPM pulley, and the speed box provides a lower frequency waveform running the motor more slowly while still turning the platter at 33.33-RPM. Pushing the 45-RPM button increases the AC frequency turning the motor faster and the platter at 45-RPM - providing electronic speed change at the push of the button. No fiddling with the belt and pulleys!

Plugging the box into the wall-wart and measuring the output voltage from the speed controller resulted in a more reasonable 16.83V and a frequency of 44.32Hz at the 33-RPM setting and, as expected, 59.9Hz at the 45-RPM setting."



Copying from an earlier post:

On the Box:
Type: 9423 90 000
Motortek 9423
16v 60hz 2va 300n./min.
Made in the Czech Republic

On the Motor:
Pro-ject
Synchromotor
M400
Hz 50 60
C 8u2 8u2
ot/min. 300 360

The first set of specs seem to validiate the distributor's claim that at 60hz, you get 300 rpms; the other specs muddy the water (and suggest, perhaps, a faster speed of 360 rpm). Perhaps its necessary to move the belt to the 45rpm section of only a 50Hz pulley and the combo will work fine with a standard AR 60Hz pulley belted at 33-1/3. I can't do the math but am hopeful that with the belt placed on either the 33 or 45 rpm section of an AR pulley, this thing will spin at the right speed. Given the frequency output measurements from the Speedbox (45 and 60Hz), I'm betting that the AR pulley would need to belted at 45 Hz in order to get the right speeds.

[rkay5]

Hi JXO,
When you use the Speedbox mkII in the US ant turntable must use the 45rpm pulley because when the 24 pole motor is powered with 60Hz it speed is 300rpm (60 hz / 12 x 60 = 300) @33-1/3rd platter rpm and so (44.32Hz/12 x 60 = 221.6rpm so you must use the bigger pulley the math makes it easy to see. You should not have any problem with using your AR pulley as it looks like the Pro-ject motor is a 24pole motor and if it fits on the motor shaft if it doesn't you can find someone make one for you. you could email Dave over at the http://www.vinylnirvana.com/
Once you get up running you going love the better sound. Also one thing I did to my Speedbox was make a new PSU for with AVEL 30VA 15V+15V TOROIDAL Transformer it is a big help to the Speedbox I think cleaner power and more current 2 amps, it does say 15V but its more like 17.8V I really love what Speedbox does for my Thorens also it runs speed prefect 33 1/3 +/- 0.012% and at 45 +/- 0.1% Robert

[JXO]

.... You should not have any problem with using your AR pulley as it looks like the Pro-ject motor is a 24pole motor ...

Also one thing I did to my Speedbox was make a new PSU for with AVEL 30VA 15V+15V TOROIDAL Transformer ...

Thanks Robert, hope it works.

How difficult was the mod to the PSU? Was it a simple swap of the existing transformer or was it more involved? any further detail would be appreciated.

Jim

[rkay5]

Hi Jim,
The upgreade using the AVEL 30VA 15V+15V TOROIDAL Transformer is very easy simple swap out of the stock transformer I used a old Audio Alemey psu box for the transformer a 320IEC connentor for high end power cord and a 3 ft 18awg cable with 2.5mm connentor to hook to the Speedbox you can put in on-off switch and wire in a fuse if you want but I didn't and works great.Have Fun Robert

[JXO]

Stuff started arriving. Speedbox is here. Problem number one: the cable from the Speedbox does NOT fit into a 2.5mm power jack that I ordered from PartsExpress.

The power jack is found here:

http://www.partsexpress.com/pe/showdetl ... er=090-479


The center pin in the power jack seems to be too big for the Speedbox plug. Perhaps it's a 2.1m connection. The Speedbox cable plugs perfectly into its own power jack.

I was surprised at how small the Speedbox is; but the build quality seems very high.

[MuZak]

Stuff started arriving. Speedbox is here.

WooHoo!!!
Bout dang time, eh?!

Problem number one: the cable from the Speedbox does NOT fit into a 2.5mm power jack that I ordered from PartsExpress.
The center pin in the power jack seems to be too big for the Speedbox plug. Perhaps it's a 2.1m connection. The Speedbox cable plugs perfectly into its own power jack.

Fooey!
Maybe its some wierd proprietary thing thats designed
to foil attempts at doing what you're doing.

Might have to resort to cutting it off and splicing
something else on, or putting a jack in the box.
Eeek!

I was surprised at how small the Speedbox is; but the build quality seems very high.

Hmm.. interesting.
It does look kinda big in the pix...

Glad to see its finally comming together...
sort of..
Hope your path ahead is clear of any further obstacles or difficulties!

G

[JXO]

Might have to resort to cutting it off and splicing

I will order a few other DC power jacks to see if I can find one that fits; if not, surgery time.

Heading to Asia for 10 days so the project will go cold for a while.

[reverber]

If you take it to Radio Shack, they have a selection of plugs (for when you buy a wall wart ps) that you can try out to get the correct size.

Cody

[JXO]

It's a 2.1 mm plug.

[MuZak]

I was waiting anxiously to see what else is nescessary
to complete the project!!!

Not to mention how it came out, and how it sounds?!??!

JXO... I'd be real greatful to find out the rest!

Thanx,
Greg

[JXO]

I was waiting anxiously to see what else is nescessary
to complete the project!!!

Not to mention how it came out, and how it sounds?!??!

JXO... I'd be real greatful to find out the rest!

Thanx,
Greg

The wheels of progress turn very slowly. Objective number 1 was to have my dealer install a new tonearm cable and cartridge-- it sat with him forever. It's finally back as of 2 weeks ago but the cartridge needs to be replaced.

I believe I have everything to begin toying with the motor upgrade; hopefully, I will get a chance in the next week or two. keep you posted.

[JXO]

will try to install and wire the motor to the speedbox this weekend.

One question: the female 2.1mm connector has 3 connection terminals. With only 2 wires coming off the motor, which ones should be used?

Here's an example (no wiring instructions came with any of them):

http://www.partsexpress.com/pe/showdetl ... er=090-488

the image shows 2 of the three connection terminals.

My initial connection strategy:
1. replace existing Hurst with Project Motor (looks like an easy swap; have nylon connectors as well as the original screws)
2. insert the capacitor in the metal housing in the plinth; just wire the motor to the capacitor then to the switch
3. use the existing power switch
4. use the existing power cord; remove the plug and install the 2.1mm female connector
5. connect the speedbox to the turntable cable and cross my fingers.