TT Speed Control/ Phoenix Roadrunner and Eagle Review

I’ll start by saying that I have absolutely no affiliation with Phoenix Eng, have only spoken with them for customer support and am purely posting to share my direct personal experience.

I own a Basis 2800 TT which I’ve been very happy with but as an audio enthusiast I’m generally considering or open to upgrades, hoping to refine my systems sound and get the most out of it. 

Using a KAB strobe and testing the Basis, it was very far off the mark speed wise. The Basis speed controller, the Syncrowave (speed control +) costs about 5k new, way more than I was ready to spend. I’ve had the VPI SDS, when I owned a Classic 3 and thought it provided a significant improvement, so figured I would try to get something going on the Basis.

While the SDS and Walker seem to be the most popular and available choices, I continued to poke around.  I found some images of the internals of the Walker and was quite surprised at the seemingly low build quality in relation to the price. It also took a few minutes to let idea sink in that these units did nothing to adjust speed in real time.

More research led me to the Phoenix Eng. site and their products, Roadrunner Tachometer and Eagle PSU (Power Supply Unit). For those unfamiliar with these products, the Eagle PSU apparently creates a super stable current flow to the TT motor so it can maximize it’s design potential without inconsistent power fluctuations interfering. There’s a very cool Youtube vid showing the stability of the sine wave. In my understanding the Roadrunner works by sending a signal from a small sensor on the plinth that tracks the real time rpms of the platter by detecting a tiny magnet that is mounted on the underside of the platter to the RR (Roadrunner) unit. The RR then assesses the rpms and when tethered to the Eagle adjusts current and speed to bring the platter into perfect speed within .005 rpms/min. .005!!! The Roadrunner and Eagle controller box are very small, about the size of a deck of cards, and the Eagle transformer about 2"x4"x8", nicely designed and easy on the eye.

For some reason the first Eagle I received was not working for me and I wound up contacting Phoenix directly and talking and working with Bill, who I believe is the owner, engineer etc. He spent a good 45 minutes on the phone with me and when we couldn’t get things up and running he arranged an exchange and express mailed it to me the next day. Class act.

I believe that the Phoenix units will not work with a motor that has any type of speed control chip built into to it (definitely double check with Phoenix if you want to make sure), and I made a call to Basis to confirm that their motors do not. 

Unlike every other speed control that I’ve checked out, where you set a speed and hope for the best, this real time, on the fly calibration insures proper speed at the beginning, middle and end of the lp, eliminates issues around stylus drag, belt tension, lp weight and energy fluctuations from outlets.

Seeing the speed lock in at 33.333 is a thing of beauty, and while there is some drift, it’s minute, always staying within the .005rpm/min. design parameter. 

The sound improvement is quite obvious to my ear. I’m aware of the psychological tendency to like what you’ve just spent money on and want to believe it’s helping, but I really do like these products and they are really are helping :)
Seriously, bass, soundstage, imaging, reduction in sibilance, are all improved. The music sounds better.

In my opinion there are some extremely minor issues with aesthetics of the rpm sensor that affixes to the plinth, purely visual, and just a matter of taste. 
I wish there was a way to have the display either go blank after a fixed period of time or have the option to manually turn it off, which I do not believe is a feature at this point.

For anyone considering a speed control solution, these are extremely worthy candidates being very well designed, doing exactly what they’re supposed to do and doing it flawlessly, decent looking and good value for the money. For me an easy 8.5/10.

Hope this can be of help.

There is an app you can download from the App Store called Platter Speed, invented by the famous Dr. Feikert.  You play a 3150 hz tone from your turntable (available on most test records) it will give you an accurate platter speed....the app is free, ... a test record will be about 20 dollars or so.  Try it, you'll like it.
Yes, but this leads back to the question of what do you do when you realize that the speed is off?
stringreen, how do we know that the test record was recorded at exactly 33.3333 etc?  How do we know that the record hole is perfectly centered?  I have Dr. Feikert's  Adjust+ test record plus two other test records with a 3150hz test tone and they ALL give me different results using the Platter Speed app. 
The ear is king. I will never forget the improvement wrought by a Walker Audio Precision Motor Controller on the sound of my Nottingham Hyperspace tt.  It was jaw-dropping, especially because I was a complete sceptic to begin with; I was not prepared to hear an improvement at all.  That was at least 10 years and one paradigm conversion ago, for me (from belt-drive to idler- and direct-drive).  Now we have these more complex devices that can do the job even better.  So, if it sounds good-er, it IS good-er. I am not surprised. And the Eagle stuff is a stone cold bargain in terms of cost.

Though speed stability is very important (who wants wow?), in my opinion, what is really needed is voltage reduction to minimize the synchronous pulse noise from the motor.  

I use a $60 Variac on an original VPI Aries.  I start the table on 120v.  I use that voltage for light record cleaning, finishing with a carbon fiber brush.  Then I reduce the voltage to around 60 - 65v for playback.  That's plenty of voltage for the VPI motor, and that voltage level reduces the intensity of the synchronous motor pulses significantly. 

Once the speed of the table is established and locked on the ~ 60hz "grid" frequency, the table does not experience audible speed fluctuation.  At least, I don't hear speed fluctuation.  But if line-related noise is important, reducing the voltage in half will also cut the line-related noise in half.  That voltage reduction makes a quite audible improvement.

IMO, the synchronous motor pulse noise is magnitudes greater than line-related noise, but I admit never attempting to measure it. 

The SDS provides a similar voltage reduction though not as extreme as I use.  There is also the same kind of signal regeneration as the Phoenix units.  The SDS is more expensive than the Eagle / Roadrunner but includes voltage reduction where it appears the Phoenix products do not.

I have not tried a SDS unit in my system, but friends use it with very good results.

I have no familiarity with the Walker unit.

I stand corrected.  The Eagle power supply does include a voltage reduction after the platter has reached normal operating speed.
moryoga- glad to hear the Roadrinner/Eagle made an improvement for you.  I was going to try one with my Amadeus, but heard they aren't compatible with DC motors. Maybe I will look in to other options. 
I owned the Basis 2500, and it's an excellent table.  Cheers -Don
moryoga: do you have a Signature Series Basis 2800?
The Road Runner sensor/magnet requieres 0.25'' of clearance between platter and plinth. I have an old Basis 2001 that doesn't have this clearance by a small margin.
Do you have any issues placing the magnet in the platter and the sensor in the plinth?
Could you share your experience?

bipoletti, glad you discovered the voltage reduction bit, and sorry I forgot to mention it in the first place. I agree, a very important aspect and consideration. 

juan11, I do have the 2800 Signature and it has exactly (I'm sure to the micron like all things Basis :) ) .25 inches. It was a huge relief when I saw it fit so perfectly.

fjn04, bummer on the DC motor. Wonder if there's a work around, or possible DC model. Have you checked in with Bill at Phoenix?

Moryoga- I haven't. Maybe I should but figured it is what it is.

Funny thing is I could have swore a dealer told me he tried a

Walker on an Amadeus. Then when I looked up the Walker,

it said for AC motors as well.  Cheers -Don

Does anyone have any thoughts on how low to set the voltage reduction on an Eagle? How low is too low? What will happen when one reaches the sweet spot of effficiency and performance? The manual instructs clearly on how to achieve the reduction but provides no rule of thumb or guidlines as to where to set it. Someone above suggests 60-65, I am curious how one arrives at this setting. Thanks in advance....

I use the Phoenix/Roadrunner combination on my VPI HW-19 MkIV, it makes a very nice improvement. I really enjoy the fact that I can look over and see where the platter RPM is currently at. Come to think of it I’ve been looking over less and less and enjoying more and more lately. Been using mine for almost a year now with no issues. I also like the fact that I have the ability to convert it to run 78 ARM, while I have yet to do this, it will be a future use item.

P.S. Nice review by the way, great description of the product.

I'm sorry to say that I not only don't know the answer to that question but I wasn't even aware that dialing in minimum voltage was an option. I'm obviously a newbie at leaving reviews and certainly need to be more familiar with the product before I decide to leave another.  

Super cool feature though and I'll definitely be looking into it. If you figure it out in the meantime please post about what you come up with. 


The lowest possible voltage on the eagle is 85 volts.  Set it there.  If your TT works well, and it probably will, just leave it there.  If you have a problem, raise the voltage in steps until you have no problem.

That's it!
From the Phoenix wed site, the Eagle Owners Manual:

go to page 4 "Voltage Output Mode"
Also, very cool and informative vids from Phoenix here:

This is the video of our PSUs vs the VPI SDS:


The link is for part 1; the link for part 2 is in the comments section.

Nice review moryoga