Phoenix Engineering Falcon PSU Turntable Speed Controller

We don't have a complete BOM as of yet, but we're hoping to target ~$500-$550 retail.

 

Hey Bill,

Will the new beefier PSU work with the Roadrunner box? Any idea of intro date?

 

Drew769-

The new PSU will definitely work with the tachometer. The high power PSU will be a 2 pc unit. The controller is the same size as the Falcon and all of the user interface and tachometer interface is exactly the same (same features as the Falcon). The output of the controller will be 5V and will connect to a larger amplifier unit that can be located remotely. The output of the amp will be 15W max. There will be only one wall adapter for the new PSU, the controller will get its power over the same cable that connects its output to the amp.

I have most of the metal work in house, the PCBs just went over to the CM for population and I'm waiting to hear back on a quote for foam packaging. If all goes smoothly, I hope to be shipping product by the end of this year.

I have a limited number of 5W 300 RPM motors and pulleys available, but the solution didn't turn out to be a viable direction.

 

Sounds good!

 

This thread has gone on for a while. I have read it and I'm impressed at the experimentation. I'm also impressed with Bill's openness to make a motor group buy and increase the output of the power module. That is a considerable monetary investment for Phoenix and a commitment to the table community. Not to mention my respect for his well thought out product.

I have an old VPI HW-19 (original, no Mk). I know a number of guys who have the early generation tables and today very few run at specified speed. Mine definitely runs slowly. So this "affordable" speed control system is a boon to us who are not going to plunk down $5000 on a new table. Mine works well and has no noise when listening to the bearing with a stethoscope. It is dead quiet, well built.

I'm impressed that the controller allows you to trim both 33 and 45 RPM speeds to be accurate then set it and vary the speed if you need. What a boon. You could play early releases of Kind Of Blue at the proper speed.

As I read through the thread 99% of the posters liked the effect the PSU and Roadmaster had on the music. That speaks loudly.

Initially I was very concerned that the Tach only had one feedback per revolution, every 1.8s at 33.33 RPM. That is very low feedback compared to motor controls I have used in industry. We had 512 PPR tachs that functioned in quadrature; they were in effect 2048 pulses per revolution. As I read through the thread I came to see that higher resolution would bring hunting and unsteady speed. It would be chasing its tail. Watching the controller and tach zero in on the right speed convinced me that making an adjustment every 1.8s helps the table zero in on the correct speed.

Does moving the magnet toward the center give a less sharp transition than having the magnet toward the outer part of the platter? I expect the transition onto and off of the magnet is what triggers the tachometer count.

On Audio Karma a few years back there were discussions of VPI replacement motors. My friend Paul bought a Hurst Permanent Magnet AC Synchronous Direct drive motor for his VIP HW-19 (original). It is working well off of a PS Audio P500. The P500, however, does not have a voltage drop off after the motor is at speed. Here is a link to the page:

http://www.hurst-motors.com/papbdirectdrive.html

I will need a 3203-001 ($76.61 plus shipping). It is 600 RPM, 10W. But the wattage is only at startup. It settles down after the speed is reached in a couple of revolutions. I'll use my Kill-A-Watt to measure the startup spike and the steady state running power. I'll report back.

Bringing me to another point. The effort to start a motor is much higher than the effort to continue turning it once it is started. Motor torque is a resultant of the motor current. The current drops as the applied voltage drops.

Power = V*I*cosΦ, where Φ is the angle between the voltage and current waves. That angle is usually small so just estimate V*I. And dropping the voltage to half reduces the torque and cogging because the platter drive system doesn't exhibit the same resistance to rotation once it is started.

Bill, you have a convert. I just have to figure out how to buy the whole system on SSA retirement.

 

In theory, the larger the diameter path the magnet takes the less ambiguous the trigger should be, but this only becomes a problem at extremely small diameters. I have had customers install the magnet on smaller subplatters on Rega and Linn Turntables without any problems. Also, the closer the magnet comes to the sensor, the more consistent the trigger.

The current draw in an AC synch motor is almost wholly determined by the impedance of the coils which is dominated by the resistive component. The back EMF generated as a result of the rotating magnet within the coils is minor, but measurable. So the current consumed by the motor will be nearly constant regardless of torque until the cogging torque is exceeded, the rotor stops completely and current increases only slightly. As you noted, the only way to make a significant change in current consumption is to reduce the voltage.

I'm using the 10W Hurst motor you listed for testing the high power version of the PSU (Eagle). It measures ~9.1W, and as you mentioned, the power factor is in the high .90's. Dropping the voltage to 100V after the platter is moving reduces the power consumption to ~7.1W. This would still be quite high for running the Falcon, but the heatsink of the Eagle stays under 110°F, even after several hours continuous play.

 

Bill,

I did not know about the power consumption on a synchronous motor. I'm familiar with AC induction motors and DC motors into the 1,000 Hp. range. My experience with synchronous motors are those with slip rings feeding a rotating electromagnet in the center, all over 1,000 Hp. Smaller synchronous motors are mostly a mystery to me. I used to work at an Alcoa rolling mill built in 1942 (I wasn't alive then).

I appreciate the information!

It is good to hear that I can mount the magnet below the platter and inboard with no ill effects.

I pulled out my Killawatt and plugged my VPI HW-19 in. It pulled 4.8W starting and settled at 4.7W. The power factor was up in the 90 range. Exactly what you experience. Looks like I have the low power motor. I should keep it and see if the speed consistency is good.

 

Yep. Sounds like you have the 5.5W motor. I too had this motor in my Hw-19 but after thirty-some years of play, it became a noisy, vibrating thing that had to be replaced. VPI special orders a new 5.5W motor from Hurst that is quite a bit more expensive than the 10W 3203-001 version. But in the end it was well worth it because it allowed me to use the Falcon without any issue. And now I rest easy knowing that my slow HW-19 is now running at the proper 33.3.

Kudos to the people at Phoenix Engineering for providing such an excellent and affordable solution for turntable speed control.

 

Pappas, what kind of noise? I have done the stethoscope on the plinth trick and it is dead silent. Is there something I don't know about?

Thanks.....

 

If you're using a stethoscope and it's dead silent then it's probably safe to assume you are not missing anything. My motor was so noisy that I only needed to put my ear a foot away to hear the motor running. Not to mention the vibration that I could feel just by touching the plinth.

I DIYed the replacement motor into a home-made SAMA with some very nice results.

 

Thanks for the reply. I was not ignoring you, I was in the hospital and all doped up. It was scheduled. So I'm getting better now.

Grainger

 

DKS4, Jeff and others:

We will start shipping the Eagle PSU on Monday Dec 22nd. The hardware is complete, assembled and tested and the only thing we are waiting for is the packing foam which will arrive on Monday. The Eagle is jumper configurable for 230VAC output.

 

I too have an ingenium & I tried it with the new Pro-ject speedbox DS strobo, which going by the specs should work. Although it worked perfectly at 33, when I switched to 45, the motor sped up then stopped. I'll check to make sure the controller itself isn't faulty and luckily the dealer is happy to take it back. I am now told the Avid motor is not compatible with speed controllers, so I don't know what the Falcon does differently. I just re read the review & although it talks about speed stability it doesn't mention speed change, but I assume this was tested. I would say audition if possible before using with the Ingenium

 

The Falcon is very different from the MH Cruise Control or Pro-Ject Speedbox DS, which are both rated at 3W max. These devices use a very small (6VA) output transformer that has a high output impedance; when a load is put on the output, the voltage will sag, a lot. The Ingenium motor is rated higher than 3W and is most likely swamping the output of the Speedbox. The Falcon does not use an output transformer, its output amp is directly coupled to the output and has very low output impedance. The voltage does not sag when you connect a proper load to it.

You can read a comparison between the MH CC and the Falcon here:
http://www.phoenix-engr.com/Review One.html

Michael Fremer reviewed the Avid Ingenium table using a Falcon PSU; you can read the review here:
http://www.analogplanet.com/content/avid-“ts-off”-low-priced-ingenium-turntable

The Eagle is higher power than the Falcon and will run the Avid table with less problem than the Falcon. It is also capable of 230VAC output where the Falcon is 115VAC output only.

I don't know who told you the Avid motor wasn't compatible with a speed controller, but they are wrong. It is only not compatible with underpowered controllers.

 

I see. Well I appreciate the explanation. I just wish dealers knew more about the products they were selling. Anyway no damage done as they restocked the Pro-ject. My mission now is to find a controller that will work. The Eagle would seem like a no brainer with it's 230VAC /50Hz capability as I live in the UK. Unfortunately we have to deal with import duty & shipping plus we usually get hit with handling fees this end. All up it would add over $200 to what seems like a good value piece of kit - and I guess I'd also have to source adapters, which should be easy enough. Ah well, you guys seem to have all the best stuff

 

where can i find the eagle?

 

You can find a scrolling list of dealers on our website here: http://www.phoenix-engr.com/#!/page_dealers

We also sell direct.

 

I just purchased the Road Runner alone from Phoenix Engineering. In time, I will add the Eagle speed controller, but the Roadrunner is a great place to start. The Roadrunner makes it easy to see the exact speed of the table and make adjustments to compensate. With VPI's stand alone motor on my Scoutmaster, I was able to move the motor slightly closer or away from the table to get the speed very close to 33.3 or 45 rpm, while also experimenting with the belt placement on the variety of pulley options that VPI gives you with their motors. I realize that the Eagle would lock the speed "dead on" as well as lower the voltage to the motor for a reduced vibration, but the roadrunner is a good place to start. It's never been easier to have a speed readout to five decimal places before. No more using strobes and trying to adjust my eyes to see the squares going by. Plus, the Roadrunner allows me to see the speed with the arm down on the record groove. Nice Product!!

 

Question for Phoenixengr: I have a Gyrodec with the AC papst motor, will the Falcon have enough power to drive the motor safely? Also, does the hall sensor for the Roadrunner mount easily to the Gyrodec?

 

Has anybody used the Falcon with a Gyrodec with the AC papst motor?

 

Tt

 

How accurately does the Falcon PSU hold the platter speed without the Roadrunner? I know the Roadrunner tach can signal the Falcon to precisely adjust the rpm but does it also hold the Falcon to tighter tolerances in speed variation?

Edit: Ah, never mind, looking at the website I se the rpm variation is the same for the Falcon or Falcon+Roadrunner at +-0.005rpm.

 

Any chance of another Group Buy for the Falcon PSU?

 

I'm in! Well, I would be...

 

I would also be interested.