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Finally! Automatic Speed Control...

74.130.29.193
Posted on January 12, 2017 at 21:03:21
John Elison
Audiophile

Posts: 23900
Location: Central Kentucky
Joined: December 20, 2000
Contributor
  Since: January 29, 2004
 I replaced the stepper motor in my Sota Millennia Vacuum turntable with a 3-phase motor and controller made by Phoenix Engineering. It's a prototype that never went into production, but Bill Carlin was nice enough to sell it to me so I could have automatic speed control for my Sota. I didn't expect to hear any difference, but I truly believe this new system produces greater clarity and tighter bass than before. It also might improve dynamic range a bit, too. Anyway, I'm very happy with the results and I will be playing more vinyl as a result.

After buying the Phoenix Engineering RoadRunner tachometer a couple of years ago, I noticed that my turntable had a very long warm-up cycle. Of course, the Sota motor had fine speed adjustment so I could adjust it for accuracy but I had to keep adjusting it for nearly two hours before it finally stabilized. In fact, if I just turned it on and let it run it would start at about 33.100-rpm and gradually increase in speed for nearly two hours before stabilizing at 33.333. Because of this, I would generally let it warm up for two hours before doing any vinyl recording.

Now, I can turn it on and within seconds the platter speed stabilizes at 33.333 +/-0.003-rpm. It's like having a quartz locked platter. Of course, all you inmates with Eagles and RoadRunners know how nice they are but I've been living with the RoadRunner only for the past two years. This new system is absolutely fantastic.

Best regards,
John Elison



 

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RE: 33.1 to 33.3 Audible?, posted on January 13, 2017 at 04:31:24
kitch29
 During this warm up could you hear the speed changes as Wow and Flutter or were you merely following them on the read out?

I don't have the Math Gene...the change from 33.1 to 33.333 is .06 per cent? You can hear that?

 

RE: 33.1 to 33.3 Audible?, posted on January 13, 2017 at 04:47:02
volunteer
Audiophile

Posts: 5666
Location: Louisville, KY
Joined: January 7, 2012
 It might be. Too slow is more detrimental than a little fast.


-Wendell

 

RE: Finally! Automatic Speed Control..., posted on January 13, 2017 at 04:51:52
Not Yet There
Audiophile

Posts: 538
Joined: April 8, 2006
 Very nice John. Any plans on trying to retrofit the new motor into the old SOTA enclosure?

 

RE: 33.1 to 33.3 Audible?, posted on January 13, 2017 at 06:07:07
kentaja
Manufacturer

Posts: 4614
Joined: March 26, 2001
 Unlikely. It will manifest as a change of tone more than anything. My Lenco does the same thing. Takes several hours for proper speed give the bearing fluid.

 

RE: 33.1 to 33.3 Audible?, posted on January 13, 2017 at 06:10:11
kentaja
Manufacturer

Posts: 4614
Joined: March 26, 2001
 'Too slow is more detrimental than a little fast.'

A matter of personal opinion/taste. The type of speed error, broad over time, is going to impact tone more than anything. Too fast and tone will be shoved up. Too slow and tone will be shoved down. I much prefer tonal balance changes that are down rather than up.

Timing, etc., and other factors will be impacted by improper speed but is shifts in tonal balance is what will be the most apparent.

Of course that is provided one is sensitive to minor shifts in tonal balance. Some me more bothered but the change in timing, etc.

 

RE: 33.1 to 33.3 Audible?, posted on January 13, 2017 at 06:12:39
volunteer
Audiophile

Posts: 5666
Location: Louisville, KY
Joined: January 7, 2012
 Can only speak to my experience. I may not notice a little fast. I seem to always be aware of a little slow.


-Wendell

 

33.3 + .003= 33.303, posted on January 13, 2017 at 06:46:29
TomWh
Audiophile

Posts: 764
Location: Tucson Az
Joined: August 7, 2003
 The road runner is showing 33.333 as perfect. So if I read this correcty John is seeing 33.330-33.336. Then the question arises how chose where all the albums made to that 33.333 number???

Enjoy the ride
Tom

 

RE: Finally! Automatic Speed Control..., posted on January 13, 2017 at 06:58:20
TomWh
Audiophile

Posts: 764
Location: Tucson Az
Joined: August 7, 2003
 John

Nice score!!! You got something even us DIYers do not have, feed back on a 3 phase controller. Bill is a 1st class guy who knows his stuff. We can only hope he will stay in touch with the DIY community.

Enjoy the ride
Tom

 

RE: 33.1 to 33.3 Audible?, posted on January 13, 2017 at 07:26:25
kentaja
Manufacturer

Posts: 4614
Joined: March 26, 2001
 Agreed. Our own experience is what matters. I just did not agree that a little slow is bad.

I hear both fast or slow but I am very sensitive to minor tonal balance shifts.

 

RE: Finally! Automatic Speed Control..., posted on January 13, 2017 at 07:32:07
rrob
Audiophile

Posts: 762
Location: Kansas
Joined: February 7, 2010
 Very nice John

 

RE: 33.1 to 33.3 Audible?, posted on January 13, 2017 at 08:11:02
John Elison
Audiophile

Posts: 23900
Location: Central Kentucky
Joined: December 20, 2000
Contributor
  Since: January 29, 2004
 Actually, the difference between 33.1 and 33.333 is 0.7%. I don't think I heard the difference because it didn't manifest itself as wow % flutter. It was a gradual drift over a long period of time. However, it annoyed the heck out of me and it was totally unacceptable for a ten-thousand dollar turntable. Also, the fact that Sota used a stepper motor as a turntable motor is very unusual if not truly a bad design choice. Stepper motors have the maximum amount of cogging of any motor. Of course, the massive platter combined with the elastic belt should have isolated the LP, but I truly believe I hear an improvement with my new 3-phase motor and controller.

Best regards,
John Elison

 

RE: 33.3 + .003= 33.303, posted on January 13, 2017 at 08:28:14
John Elison
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 I'm not sure why that question would arise, but its my impression that cutting lathes are direct-drive and exceedingly accurate. They are probably quartz locked direct-drive like my Technics SL-1200 turntable. I measured its average rotational speed to be accurate to 0.0008% at 33.333-rpm. This equates to an accuracy of 0.0003-rpm, which is one-tenth the error of my Sota Millennia turntable with its new motor.

Best regards,
John Elison

 

RE: Finally! Automatic Speed Control..., posted on January 13, 2017 at 08:54:47
John Elison
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 I don't have any plans for that, but if I were Sota, I would make plans. I think they could easily revamp their top turntables with this 3-phase motor and controller to become the best belt drive turntables on the market. Furthermore, if they weren't greedy they wouldn't even have to raise their price. I'm pretty sure this system could easily be incorporated into a ten-thousand dollar turntable with plenty of profit left over. They would have to talk to Bill Carlin about it, though.

Best regards,
John Elison

 

RE: 33.3 + .003= 33.303, posted on January 13, 2017 at 09:28:39
TomWh
Audiophile

Posts: 764
Location: Tucson Az
Joined: August 7, 2003
 My point was 33.1 is a far cry from 33.330 and to think the music business was that concerned about .003 rpm to keep constant tabs on it would surprise me!!!

Regardless of all the quessing I bet that sota platter loves being hooked to a high quality 3 phase brushless DC motor.

Seeing you have direct drive table and the new sota combo maybe if Bill has a extra pick up you could throw one on the techniques and see if the road runner stays at 33.333. That would be interesting from the wow angle but still not answer can anyone hear a pitch difference of .003.

Enjoy the ride
Tom

 

RE: 33.1 to 33.3 Audible?, posted on January 13, 2017 at 10:03:38
TomWh
Audiophile

Posts: 764
Location: Tucson Az
Joined: August 7, 2003
 It seems no body is looking at the numbers. John wrote .003 +/- . That is 33.330 to 33.336 rpm. Your number is .233 which is over 75 times higher. You can easily hear 33.1 vs 33.333. Can you hear 33.330 vs 33.333? Pitch I would question. Wow is anyone's guess.

Tom

 

RE: Finally! Automatic Speed Control..., posted on January 13, 2017 at 10:28:52
AudioSoul
Audiophile

Posts: 4594
Location: north central AZ
Joined: July 9, 2005

That's great! the only one in existence. Did he happen to say why he went out of business?

 

RE: Finally! Automatic Speed Control..., posted on January 13, 2017 at 11:04:33
Mel
Audiophile

Posts: 2993
Location: New York City Area
Joined: February 21, 2001
 John,

Congrats on an interesting step. For me the best thing about this monitoring and correction is that is just one more thing I never have to think about. As the man said, "Just set it and forget it." So, for a bit over a year I've been able to obsess about everything else. Glad to know that the three phase motor is working well. Bill maintains it is better than the motors for which the Falcon was originally designed.

I was aware that the usual belt driven TT needed to be "warmed up" before reaching long term stability. It was HW who wrote in his user manuals that one should wait a time before doing "critical listening." I had no idea that it could take up to two hours. Most people wouldn't know for not many will have been using a Roadrunner without the accompanying PSU. Apparently running consistently slow or fast can affect some of those aspects of space and phase that we audiophiles covet. As usual, some will hear it; others may not.

Since there seem to be no more Eagles and there are still some Falcons remaining, potential buyers may wish to know that properly heat-sinked the Falcon can be used wih larger motors than the 5 watt motors for which the Falcon was "specified." A Google search will be helpful.

Regards,

Mel

 

RE: Finally! Automatic Speed Control..., posted on January 13, 2017 at 11:26:55
Uncle Mike
 I really would like to know how that 3 phase controller would work with a Pabst motor? And how it got so small.

 

RE: 33.3 + .003= 33.303, posted on January 13, 2017 at 12:24:08
John Elison
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Location: Central Kentucky
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Contributor
  Since: January 29, 2004
 The RoadRunner does not measure wow & flutter. Originally, it did seem to measure wow & flutter, but Bill rewrote the software to incorporate an averaging algorithm to eliminating wow & flutter from affecting its reading. Therefore, if I connected it to my Technics SL-1200, it would not drift at all. It might fluctuate slightly like it does on my Sota, but it would always remain centered on 33.333-rpm.

Best regards,
John Elison

 

RE: Finally! Automatic Speed Control..., posted on January 13, 2017 at 12:52:18
John Elison
Audiophile

Posts: 23900
Location: Central Kentucky
Joined: December 20, 2000
Contributor
  Since: January 29, 2004
 Bill is a vinyl hobbyist like the rest of us. He is a retired engineer and he saw an opportunity to build something that was needed. He thought it would keep him busy in his retirement and he thought it would be fun. However, it started keeping him too busy and the fun part disappeared. This is just my conjecture from our email conversations.

However, he definitely didn't quit from lack of sales. His products are made from the highest quality parts and they filled a need that hadn't been fully explored or undertaken. Furthermore, they were very reasonably priced. It's truly a shame that he is out of the audio business.

Best regards,
John Elison

 

Cool, posted on January 13, 2017 at 13:03:49
E-Stat
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 I guess it was frustrating to have the RoadRunner indicate what you could not previously fix.

I'm enjoying my Eagle, too.

 

RE: Finally! Automatic Speed Control..., posted on January 13, 2017 at 13:28:46
John Elison
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Posts: 23900
Location: Central Kentucky
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  Since: January 29, 2004
 You'll have to contact Bill Carlin directly. I can't answer your questions because the operators manual for the Condor does not specify output power. The only specification I can find that might give some inkling of power is the input voltage and current requirements, which are 24-volts DC at 500-mA for normal operation. Therefore, its output power cannot be greater than 12-watts total for all three phases combined. Of course, there will be heat losses in the amplifier so its actual output power might be only 6 or 8-watts; I really don't know.

Best regards,
John Elison

 

RE: Finally! Automatic Speed Control..., posted on January 13, 2017 at 15:52:32
PMEL324X0
Audiophile

Posts: 124
Location: Tacoma
Joined: January 6, 2008
 Bill should have sold that business to someone!!!!!

 

RE: Finally! Automatic Speed Control..., posted on January 13, 2017 at 17:00:23
MikeWI
Audiophile

Posts: 632
Joined: March 22, 2002
 Very nice! I really like my true 3 phase regenerated drive for the ROK Papst motor. I don't have feedback control but have never noticed any instability. I'll have to look at it specifically to see if there are any time based drifts.

My experience was a very significant step up from faked 2 phase drive to true 2 phase drive and a very nice "polishing" upgrade in sound from the true 2 phase to true 3 phase.

The Papst motor needs about 40 watts. I have Mark Kelly's (discontinued) 3 phase generator and then I designed my own power output stages.

Mike

 

RE: Finally! Automatic Speed Control..., posted on January 13, 2017 at 18:58:15
John Elison
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Contributor
  Since: January 29, 2004
 Thanks, Tom!

Yes, Bill is a 1st class guy and an excellent engineer. I'm sure he will remain involved with the DIY community.

Thanks again,
John Elison

 

Thanks! , posted on January 13, 2017 at 19:01:35
John Elison
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 I owe my thanks to Bill. He made some exceptional products.

 

Thanks!, posted on January 13, 2017 at 19:10:20
John Elison
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Location: Central Kentucky
Joined: December 20, 2000
Contributor
  Since: January 29, 2004
 I lucked out and bought an Eagle, too. I was thinking of using a regular synchronous motor before Bill offered me this 3-phase system.

 

RE: Finally! Automatic Speed Control..., posted on January 13, 2017 at 19:17:48
John Elison
Audiophile

Posts: 23900
Location: Central Kentucky
Joined: December 20, 2000
Contributor
  Since: January 29, 2004
 This little BLDC motor seems to have plenty of torque. It brings my 15-lb platter up to operating speed in less than 12-seconds. I don't know its power requirement but it has to be less than 12-watts.

I haven't seen Mark around here in a while. Is he still into audio?

Thanks,
John Elison

 

Thanks, Mel. /nt\, posted on January 13, 2017 at 19:18:49
John Elison
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Location: Central Kentucky
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Contributor
  Since: January 29, 2004

 

RE: Finally! Automatic Speed Control..., posted on January 13, 2017 at 19:42:48
painter27
Audiophile

Posts: 5057
Location: wi.
Joined: January 7, 2003
 If I come home & plan on listening to albums, I power up the tt & go about business.

1/2 hour to an hour later I'll put on an album as back ground music to warm up the cart & speakers, then let er snap.

Am I right at 33 & a third; hell I don't know.. I guess it would drive me nuts if I knew.

You have found nirvana.

 

RE: Finally! Automatic Speed Control..., posted on January 13, 2017 at 20:41:28
Ugly
Audiophile

Posts: 2912
Location: Des Moines, WA
Joined: August 22, 2006
 Looks cool! I would love to try some Phoenix gear with my TD160 one day to see what happens.

 

RE: Finally! Automatic Speed Control..., posted on January 13, 2017 at 21:13:38
John Elison
Audiophile

Posts: 23900
Location: Central Kentucky
Joined: December 20, 2000
Contributor
  Since: January 29, 2004
 It sounds like you've found nirvana, too!

 

RE: If you need to check pitch...., posted on January 14, 2017 at 06:53:19
kitch29
 ...this has been around since Hector was a Pup:



There are $50 Guitar Tuners these days.

My take on this whole buy something...anything..., if your ears are discerning enough to be here and you can't hear Wow, you don't need it.

OTOH, everything makes a difference. If the Gizmo of the Month makes an audible difference in the presentation of Tone, Timbre, or Soundstage, have at it.

 

RE: If you need to check pitch...., posted on January 14, 2017 at 07:14:07
John Elison
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Contributor
  Since: January 29, 2004
 Thanks for reminding me; I have a much more modern Korg version of that thing.

However, I don't understand your point. Oh, well. Such is life!

 

Installing the sensor, posted on January 14, 2017 at 09:08:48
Lew
Audiophile

Posts: 10911
Location: Bethesda, Maryland
Joined: December 11, 2000
 John, I went and bought an Eagle and RR as soon as I came to the very belated realization that they would work on my Lenco motor. The new stuff is still in its shipping containers, but I did read the instructions on installing the sensor, where Phoenix recommends not more than a 1/8" clearance between the magnet and the sensor itself. Did you find that to be a very critical parameter when you installed yours on the SOTA? Thanks.

 

RE: Installing the sensor, posted on January 14, 2017 at 09:55:57
Mel
Audiophile

Posts: 2993
Location: New York City Area
Joined: February 21, 2001
 When it is close enough to the magnet, it lights an LED in front of the numbers as the magnet passes near. You will easily see that. If the LED doesn't light, it is too far.

 

RE: very interesting, posted on January 14, 2017 at 09:56:59
user510
 That looks like a great upgrade. How many other TT mfr's use 3-phase motors....? I keep coming up with one; SME.

I am curious about the type of 3-phase motor you have. For instance is it a true synchronous motor that locks onto the frequency? Or is it another type, like a shaded pole motor, that, while being influenced by the power frequency, can slip at its poles when the physical load gets high enough?

Is it a flywheel (ausenlauffer) motor like some of the Papst motors where the rotor is external?

Stuff like that.
-Steve

 

RE: Installing the sensor, posted on January 14, 2017 at 11:20:24
John Elison
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Contributor
  Since: January 29, 2004
 I don't know how critical the gap is because I followed instructions and mine works just fine. Therefore, I would recommend simply following the instructions and mount it so the gap is very small.

Is there a problem. I had to use a wooden block to mount the sensor because the bottom of my platter is about 1-1/8" above the top surface of my plinth.

I hope you like your new Eagle and RoadRunner. There really hasn't been anything quite like these components. They are truly unique.

Best regards,
John Elison

 

RE: very interesting, posted on January 14, 2017 at 11:53:31
John Elison
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Posts: 23900
Location: Central Kentucky
Joined: December 20, 2000
Contributor
  Since: January 29, 2004
 Hi Steve,

To be honest, I know very little about electric motors. All I can tell you is that this motor is quite substantial. It spins up my Sota's 15-lb platter in just a few seconds. Sota's platter has a fairly high moment-of-inertia because much of its mass is concentrated in a lead ring around it periphery.

The motor is a 12-watt brush-less DC motor operating from 24-VAC 3-phase sinusoidal power, which eliminates cogging completely. It has approximately twice the torque of a 10-watt Hurst AC synchronous motor and its RPM is governed by frequency. The Condor controller has a soft start function that ramps up frequency to full speed in about 2-seconds. As a result, there is absolutely no noise at startup and also no noise when running at full speed. After reaching full speed the Condor reduces voltage slightly for quieter operation, if that's even possible since it's totally silent to begin with. I get stable readings from the RoadRunner in about 12-seconds after startup, but I think the RoadRunner takes about that long to stabilize as a result of its averaging algorithm. This 3-phase system is designed to operate turntables with massive platters and it works exceptionally well with my Sota Millennia Vacuum turntable.

Best regards,
John Elison

 

RE: I'll bet..., posted on January 14, 2017 at 12:10:50
user510
 "The motor is a 12-watt brush-less DC motor operating from 24-VAC 3-phase sinusoidal power, which eliminates cogging completely. It has approximately twice the torque of a 10-watt Hurst AC synchronous motor and its RPM is governed by frequency. The Condor controller has a soft start function that ramps up frequency to full speed in about 2-seconds. As a result, there is absolutely no noise at startup and also no noise when running at full speed. After reaching full speed the Condor reduces voltage slightly for quieter operation, if that's even possible since it's totally silent to begin with. I get stable readings from the RoadRunner in about 12-seconds after startup, but I think the RoadRunner takes about that long to stabilize as a result of its averaging algorithm. This 3-phase system is designed to operate turntables with massive platters and it works exceptionally well with my Sota Millennia Vacuum turntable."
----------------
I presume that it is the motor controller that locks onto the power frequency. DC motors tend to be voltage dependent. Other words, in a DC motor, more DC volts equals more rpm and fewer DC volts means fewer rpm. In the essence of all this a motor controller for a DC motor could be as simple as a voltage regulator.

I'm not at all certain how AC 3-phase power and DC ouput come together on this. (except through an AC to DC conversion within the power supply) but I'll be happy to leave those details to its designer who has already proven himself highly competent in power supplies and motor speed regulation. Ergo, I take it on faith in its designer.

In any case it sounds as though that setup would have worked very well on a Teres.
thanks for this info John. Very interesting stuff.
-Steve

 

RE: Finally! Automatic Speed Control..., posted on January 14, 2017 at 19:13:17
painter27
Audiophile

Posts: 5057
Location: wi.
Joined: January 7, 2003
 So, now you going to rerecord every thing that you have transfer to digital from the Sota before the motor swap ?

Naa, good enough for digital.

; )

 

Thanks..., posted on January 15, 2017 at 11:28:26
Lew
Audiophile

Posts: 10911
Location: Bethesda, Maryland
Joined: December 11, 2000
 I haven't got the instruction sheet in front of me, but in addition to the bit about the LED that you relate, there is also the admonition, "The closer, the better", or words to that effect. The implication is that the device will work better and better, the closer the magnet comes to the sensor, without, of course, hitting it. That's never comforting to anyone stricken with audiophilia nervosa.

 

RE: Thanks..., posted on January 15, 2017 at 12:02:43
Mel
Audiophile

Posts: 2993
Location: New York City Area
Joined: February 21, 2001
 The "nervosa" folks may want to obsess over this, but it's not necessary. Truth is, it's a binary choice. It either trips the circuit as shown by lighting up the LED, or it does not. If it lights up consistently with each turn, it's easy to see and close enough. End of story.

With Phoenix going out of business we're fortunate to have our units. IMO they were a bargain at their price, appear well built and hopefully are bullet proof. Enjoy your combo; I enjoy mine.

 

Binary, posted on January 15, 2017 at 16:12:06
Lew
Audiophile

Posts: 10911
Location: Bethesda, Maryland
Joined: December 11, 2000
 That's what I would have thought, too. I don't quite understand why the instruction manual adds that bit about the closer, the better. Perhaps the triggering gets a tiny bit more precise as the two objects approach contact. Anyway, I've already decided not to get crazy about it.

 

RE: I'll bet..., posted on January 16, 2017 at 08:31:54
John Elison
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Location: Central Kentucky
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Contributor
  Since: January 29, 2004
 As I stated earlier, I really don't know much about electric motors, but from what little knowledge I've gleaned recently, it seems that brushless DC motors are actually AC motors in the sense that without brushes and a commutator, the motor controller must switch polarity to the motor coils in order to make it run. Therefore, the motor controller is essentially providing AC power to the motor instead of DC power. Usually, the AC power takes the form of a square wave or trapezoidal waveform, but in this particular case the stationary coils are receiving true 3-phase sinusoidal power in order to eliminate cogging. In other words, the motor coils are connected in either a Y-configuration or a delta configuration. Therefore, the Condor motor controller converts DC to AC instead of the reverse as you suggest because the Condor is powered by a 24-volt DC wall-wart power supply and must generate 3-phase AC power to send to the motor.

Best regards,
John Elison

 

RE: that makes my little brain hurt....., posted on January 16, 2017 at 15:21:03
user510
 ouch. AC becomes DC then it becomes AC again. But we call it DC becuz...uh, it likes AC going into 3 phases but then it synchronises its whatzits to the quartz crystal oscillator .... and stuff.

ok that's beyond me. Like I said early, I'll trust in the designer's ability to do this. I do recall using the 'brushed' DC motors I had on my Teres that could run either off a wall-wart that converted AC to DC, or straight off a 12 volt battery (sized about like a large motorcycle would use). But obviously this little piece of tech you have is quite different.

Pretty cool, though.
-Steve

 

RE: that makes my little brain hurt....., posted on January 16, 2017 at 15:36:34
John Elison
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  Since: January 29, 2004
 If you think about it, the commutator and brushes are there to transform DC into AC so the motor can run. You need an alternating magnetic field otherwise the motor won't turn. Consequently, aren't all electric motors really AC motors?

I've never studied electric motors and I'm just guessing. Perhaps I'm wrong! ;-)

Best regards,
John Elison

 

RE: starting to make sense..., posted on January 16, 2017 at 15:40:32
user510
 Yes. That seems likely.....and I suppose to all those who have actually studied electrical motors it should seem like one of the fundamentals. I guess a little reading up on what makes electric motors work would be useful.

thanks,
-Steve

 

RE: 33.3 + .003= 33.303, posted on January 17, 2017 at 12:23:55
bill_stevenson@bellsouth.net
Audiophile

Posts: 417
Location: West Palm Beach, FL
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 Having bought an extra sensor and installed it on my SL1200MK2, I can attest that you are 100% correct. The Technics locks at 33.333 and stays there. I still have the sensor, but have not tried to install it on my SL1200G. The result would be expected to be the same, though.

 

RE: 33.1 to 33.3 Audible?, posted on January 17, 2017 at 12:38:58
bill_stevenson@bellsouth.net
Audiophile

Posts: 417
Location: West Palm Beach, FL
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 On my VPI Prime the addition of the Eagle/Roadrunner is audible. I tried to explain this before. Let me try again. The late Joe Morello, of the Dave Brubeck Quartet, was a hero of mine. He was several years older, but we both shared the same drum teacher. Joe played Ludwig drums in those days and his bass drum was 22"x14". I had to have the same set of drums of course. To this day I still own a set of Ludwigs with the same size bass drum. On the DBQ album, Time Further Out, the first track on the second side has a drum solo. Joe was never shy about hitting his drums with considerable energy. Anyway, he hits the bass drum in the beginning of that solo with enough force to make the unwary jump. With the Eagle/Roadrunner on my Prime it is possible to hear not only his hard felt beater hit the head, but the air moving through the vent hole right on the top of the bass drum. Without the Eagle/Roadrunner, the note is clear, but the air passing through the vent hole is not audible. I could cite other examples. There is no question at all that the Eagle/Roadrunner provided an audible, if subtle difference.

 

Thanks, Bill...., posted on January 17, 2017 at 16:11:46
John Elison
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Contributor
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 Did it fluctuate at all or did it actually lock on to 33.333 and stay there?

 

RE: Thanks, Bill...., posted on January 18, 2017 at 07:09:05
bill_stevenson@bellsouth.net
Audiophile

Posts: 417
Location: West Palm Beach, FL
Joined: January 6, 2015
 No fluctuation on the SL1200MK2 for all practical purposes. My Prime fluctuates but not frequently (perhaps once every 10-15 seconds) and not by more than 0.001-0.003 all to the plus. This is not audible.

 

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