The necessity for absolute tt speed control

[morricab]

3 phase controllers with capabilities and features unheard of in 1982 have come along, computing has come a long way since too. When you combine that with older well manufactured motors you can potentially make the old girls sing again. The Forsell controller/ motor combo with its notorious instability was what i was addressing, not your Yamaha turntable, i am sure it is excellent,regretfully not many TT producers have seen it feasible to improve on that DD technology. Forsell liked belt drive air-bearing TT's for their excellent sound, a 4 phase coreless DD motor with bi-directional servo was never inside his design parameters. He was a dentist or surgeon originally, not a engineer, it is amazing how many well designed products he came up with.

You kind of sidestepped my criticism of your comments around no better tech existing when Forsell designed his TTs. My point of my Yamaha was to merely point out that suoerior tech did exist prior to Forsell’s design.
Maybe better controllers exist today but the motors have not improved beyond the best designs of the past....for audio. I am not convinced by digital control either.

 

[morricab]

Any objective data and details on its performance and way of drive. For example, I can't take seriously the use of tubes in a motor controller unless there is a technical explanation for it.

We know everything about the Papst controllers (theory and implementation) and just soundbytes about the Brinkmann. For me it makes the difference.

Only your ears should matter. Brinkmann gives an explanation for why tubes...read it. The man doesn’t make up BS...one of the more honest designers I have met.

If data matters so much to you then it is pretty easy to find a more stable speed than with a Papst motor and even an optimized controller. The motor itself has limits of precision. Doesn’t mean they will all sound better but some might and I think the Brinkmann has a good chance of doing that based on the design and experience of the designer.

 

[microstrip]

3 phase controllers with capabilities and features unheard of in 1982 have come along, computing has come a long way since too. When you combine that with older well manufactured motors you can potentially make the old girls sing again. The Forsell controller/ motor combo with its notorious instability was what i was addressing, not your Yamaha turntable, i am sure it is excellent,regretfully not many TT producers have seen it feasible to improve on that DD technology. Forsell liked belt drive air-bearing TT's for their excellent sound, a 4 phase coreless DD motor with bi-directional servo was never inside his design parameters. He was a dentist or surgeon originally, not a engineer, it is amazing how many well designed products he came up with.

Three phase controllers were common in the 60's - they are described in text books of this period. Surely they were not applied in turntables. I once consulted the Navy electronics and electromechanics courses of the 60's and was surprised with the information and depth of knowledge involved in these books. A pity they do not exist in digital format.

Poly-phase mains was discovered in the late 19th century - Tesla work on it is well known. All a three phase controller does is emulating three phase mains.

Forsell had two types of motors in his turntables - a small synchronous motor that was trouble free and a DC motor with a tachometer that was very instable. I have operated the synchronous motor with a PS Audio P300 regenerator, optimizing voltage for maximum smoothness.

Reliability was never a strong point of Forsell creations - and unfortunately the products were not assembled considering service.

 

[microstrip]

(...) Maybe better controllers exist today but the motors have not improved beyond the best designs of the past....for audio. I am not convinced by digital control either.

At some point we must consider that perhaps audio needs the imperfections of the motors of the past ...

 

[microstrip]

Only your ears should matter. Brinkmann gives an explanation for why tubes...read it. The man doesn’t make up BS...one of the more honest designers I have met.

No one is questioning the honesty of anyone. This is a subjective hobby. Please do not change the subject. Can you explain it yourself or point a direct link?

If data matters so much to you then it is pretty easy to find a more stable speed than with a Papst motor and even an optimized controller. The motor itself has limits of precision. Doesn’t mean they will all sound better but some might and I think the Brinkmann has a good chance of doing that based on the design and experience of the designer.

"Stable speed" is too poor for a technical argumentation, sorry. It is nice to know about your faith, it was not what I was addressing. But you have a good point , faith is important in this hobby.

 

[morricab]

No one is questioning the honesty of anyone. This is a subjective hobby. Please do not change the subject. Can you explain it yourself or point a direct link?



"Stable speed" is too poor for a technical argumentation, sorry. It is nice to know about your faith, it was not what I was addressing. But you have a good point , faith is important in this hobby.

Can you google Brinkmann audio?
Not sure what faith you refer to. I like science as a practical way to filter and process perceptions of whatever this is around me we call a world. It sounds like there is plenty of faith going around regarding old Papst motors though...Who knows you may even have a valid point buried in there somewhere.

 

[Lagonda]

You kind of sidestepped my criticism of your comments around no better tech existing when Forsell designed his TTs. My point of my Yamaha was to merely point out that suoerior tech did exist prior to Forsell’s design.
Maybe better controllers exist today but the motors have not improved beyond the best designs of the past....for audio. I am not convinced by digital control either.

Brad do you know of any belt drive TT's from that time that where using the technology used in your DD drive turntable ? I did not sidestep, i pointed out that i meant for a maker of a belt drive turntable. Bi-directional servos are not even feasible for current technology belt drives, as it seems to worsen, not improve the sound in that application, Brinkmann have chosen not to use any feedback loop with correction, as have most high end belt drive manufacturers. I totally agree that the motor designs for TT's in general have not really improved since back then, and as specialized motor production for TT application is probably not feasible because of low volume, companies like Brinkmann are forced to do it themselves. But on a positive note capacity and quality of hard drives have gone up, and prices down, if you like your music from a digital source.

 

[morricab]

No one is questioning the honesty of anyone. This is a subjective hobby. Please do not change the subject. Can you explain it yourself or point a direct link?



"Stable speed" is too poor for a technical argumentation, sorry. It is nice to know about your faith, it was not what I was addressing. But you have a good point , faith is important in this hobby.

Probably 10x lower wow and flutter (TechDAS specs are not more than 0.03% and a P3 at 0.003%...for example). Brinkmann gets 0.01% wow and 0.03% flutter...about the same as TechDAS.

 

[morricab]

Brad do you know of any belt drive TT's from that time that where using the technology used in your DD drive turntable ? I did not sidestep, i pointed out that i meant for a maker of a belt drive turntable. Bi-directional servos are not even feasible for current technology belt drives, as it seems to worsen, not improve the sound in that application, Brinkmann have chosen not to use any feedback loop with correction, as have most high end belt drive manufacturers. I totally agree that the motor designs for TT's in general have not really improved since back then, and as specialized motor production for TT application is probably not feasible because of low volume, companies like Brinkmann are forced to do it themselves. But on a positive note capacity and quality of hard drives have gone up, and prices down, if you like your music from a digital source.

TechDAS uses feedback and microprocessor control. In their own words...to get DD like speed control... Brinkmann gets similar numbers without feedback but both are worse, numerically, than a top DD...not that inherently wins sonically...

 

[Lagonda]

Three phase controllers were common in the 60's - they are described in text books of this period. Surely they were not applied in turntables. I once consulted the Navy electronics and electromechanics courses of the 60's and was surprised with the information and depth of knowledge involved in these books. A pity they do not exist in digital format.

Poly-phase mains was discovered in the late 19th century - Tesla work on it is well known. All a three phase controller does is emulating three phase mains.

Forsell had two types of motors in his turntables - a small synchronous motor that was trouble free and a DC motor with a tachometer that was very instable. I have operated the synchronous motor with a PS Audio P300 regenerator, optimizing voltage for maximum smoothness.

Reliability was never a strong point of Forsell creations - and unfortunately the products were not assembled considering service.

Regretfully the PS Audio P 300 did only have 5 HZ increments of adjustments, a little course for that application, it did come standard with selectable input voltage, the reason many of us American gear lovers in Europe have one. The P500 has a extra level of sub-adjustments with 32 steps for every HZ, ironically not described in the manual, and you had to specify the input voltage when you purchased it. I have 2 of those, i inadvertently bought a 120V volt input model for use in Europe, thinking it was switchable like my P300 On my second try, i got the right one.

 

[PeterA]

Probably 10x lower wow and flutter (TechDAS specs are not more than 0.03% and a P3 at 0.003%...for example). Brinkmann gets 0.01% wow and 0.03% flutter...about the same as TechDAS.

And about the same as SME.

 

[microstrip]

Can you google Brinkmann audio?

Yes, I did it. It just confirmed my ideas.

I only hope that some of the absurd things that are said there are due to poor translation. For example "We found that the vacuum in the rectifier tubes not only isolates their plates from the cathodes, but also the power line from the drive circuitry."

Not sure what faith you refer to. I like science as a practical way to filter and process perceptions of whatever this is around me we call a world. It sounds like there is plenty of faith going around regarding old Papst motors though...Who knows you may even have a valid point buried in there somewhere.

Should I remember that the faith in the old Papst is based on documented science and experience?

 

[Lagonda]

TechDAS uses feedback and microprocessor control. In their own words...to get DD like speed control... Brinkmann gets similar numbers without feedback but both are worse, numerically, than a top DD...not that inherently wins sonically...

My understanding is that TechDas uses the feedback to establish correct speed, and then automatically switches it off( i do it like that manually myself), until next time it is stoped and started again. Micro has one, and i am quoting him

 

[microstrip]

Regretfully the PS Audio P 300 did only have 5 HZ increments of adjustments, a little course for that application, it did come standard with selectable input voltage, the reason many of us American gear lovers in Europe have one. The P500 has a extra level of sub-adjustments with 32 steps for every HZ, ironically not described in the manual, and you had to specify the input voltage when you purchased it. I have 2 of those, i inadvertently bought a 120V volt input model for use in Europe, thinking it was switchable like my P300 On my second try, i got the right one.

Fortunately all turntables I owned had the proper speed at 50Hz. Remember that I am not an ultra accuracy partisan - what accuracy is good for my Studer A80 should be good for a turntable!

 

[Lagonda]

Fortunately all turntables I owned had the proper speed at 50Hz. Remember that I am not an ultra accuracy partisan - what accuracy is good for my Studer A80 should be good for a turntable!

I used my P300 on my 120V TT motor for a year before realizing that the P500 was more precise, speed was not spot on, but sound did not suffer

 

[microstrip]

Probably 10x lower wow and flutter (TechDAS specs are not more than 0.03% and a P3 at 0.003%...for example). Brinkmann gets 0.01% wow and 0.03% flutter...about the same as TechDAS.

Since long it is known that at these low levels absolute numbers of these weighted measurements are meaningless - we need spectral analysis to compare them. The effect of motors we are addressing also show outside the bandwidth of these measurements - even wikipedia addresses how poor they are.

The www.diyaudio.com forum or the Lencoheaven is a good site to follow these subjects - many people there are very knowledgeable.

 

[Lagonda]

I just read the literature on the Brinkmann Sinus motor, it talks about 16 "pulses" per revolution that again gets smoothed out by the flywheel. I count 12 poles on the regular large Pabst capstan motors, and 24 on the Studer special edition motors that i have. They where definitely made well these old motors

 

[Vienna]

I have seen, listened and experienced that one of the fundamental factors of great tt sound is the accurate speed and stability.

This is resulting in correct timing. Correct timing is an attribute which can only be appreciated the moment that will be experienced for the first time.

The inaccurate and unstable speed means timing errors, the higher the speed and stability variation, the higher the timing errors will be. (perhaps there are listeners who like this, I know people who are enjoying the distorted sound from misaligned and worn cartridges)

It’s strange how we do care about the jitter, measured in picoseconds (deviation of time between the digital and analog samples ), in the digital music reproduction, the moment that many intentionally diminishing the importance of the wrong timing on the analogue reproduction.

P.S.1 I have auditioned many turntables the last four years. Some of them with noisy motors others with very silent ones. Always the turntables (of similar specs and level) with more silent motors were yielding less vibrations and resonance measurements; and acoustically more detail retrieval, better dynamics and separation.

P.S2, Power supplies are a strange thing. A year ago Bill Carlin made me a drive with two BLDC motors driven by Class D amplifier, to replace my Hurst based motors driven by VPI ADS. The sound improvement was phenomenal. He later made for me a high biased Class AB amplifier to drive the motors and again I was amazed with the sound improvement. When I replaced the switching power supply with Keces linear one, again the improvement was huge.

Currently with Brinkmann Ront tube power supply, I am experiencing that different rectifiers are providing different sound. The Metal Base GZ34 is the best by far with great dynamics and dimensionality followed by the red lined Mullard GZ34. Sovtek is providing the worse muddy sound ever and the solid state Brinkmann BZ34 rectifier dynamic but lifeless flat sound. I don’t know whether there is a scientific explanation for this but the differences are easy to hear.

 

[tima]

I totally agree that the motor designs for TT's in general have not really improved since back then, and as specialized motor production for TT application is probably not feasible because of low volume, companies like Brinkmann are forced to do it themselves. But on a positive note capacity and quality of hard drives have gone up, and prices down, if you like your music from a digital source.

That may depend on what counts as improvement in motor design.

Slotless stator construction or slotless motors open up design opportunites for turntable makers by freeing them from dealing with torque ripple or other cogging issues and not requiring heavy platters or flywheels to address those issues.

Put your music on high capacity and high quality hard drives? The just means more high capacity and high quality hard drives for redundancy and duplexed Raid 0 backup.

 

[morricab]

Since long it is known that at these low levels absolute numbers of these weighted measurements are meaningless - we need spectral analysis to compare them. The effect of motors we are addressing also show outside the bandwidth of these measurements - even wikipedia addresses how poor they are.

The www.diyaudio.com forum or the Lencoheaven is a good site to follow these subjects - many people there are very knowledgeable.

Look at the Brinkmann Balance review in HIFI News (just google), they have detailed measurements.