VPI To Market A Direct Drive Turntable

[dnewma04]

I've seen a number of speed variation measurement techniques. I don't know if I've seen the specific method you are talking about. FWIW, I've not even said that stylus drag isn't a real/measurable issue, I think it should be relatively easy to measure/compare various drive types. Erik mentioned earlier the idea of a swappable/switchable drive mechanism. The long term DIY project has that idea built into it already. Belt drive and rim drive, currently are in the design. If I ever feel comfortable with making a motor, I might give direct drive a try in the future. If I do it, I'll even try to set up some tests to nail down stylus drag issues although my design will probably address some of his concerns with the 8 motors in belt drive mode and 4 motors in

Just to reiterate, I'm not criticizing Salvatore's ideas, it really is an interesting hypothesis and if someone decided to do some testing to validate his claims, I'd gladly read them and take a look. I'd even love to see some measurements of the noise floor of the lenco vs other idler drives and even vs top end belt and DDs. I love the crap out of this stuff. But, as presented in the article, it really tells me nothing.

 

[for_p1]

Have you ever seen one of those measuring devises? The kind that runs the test with the test disc with varying groove undulations.

I remember that virtually every table ran a tiny bit fast with no load. And I remember the guy saying that this was correct and necessary for the drag that would effect the stylus in the heavy passages. The idea is that going a bit fast would enable it to plow into the heavy drag.

I think it's obvious to most that given the micronic level that stylus drag would takes place at. The speed variations that the guy discussed were visible on the printout and every table handled them differently.

Marc mc

Given access to modern signal processing technology (whch is cheap in comparison with any decent TT setup), the only limit for even DIY measurement is absense of required test records.

 

[marc mc]

Just to reiterate, I'm not criticizing Salvatore's ideas, it really is an interesting hypothesis and if someone decided to do some testing to validate his claims, I'd gladly read them and take a look. I'd even love to see some measurements of the noise floor of the lenco vs other idler drives and even vs top end belt and DDs. I love the crap out of this stuff. But, as presented in the article, it really tells me nothing.

You can't hear it, you said that. So what possible good would claims validated by claims accomplish?

Marc mc

 

[dnewma04]

I don't believe I said that but if I did, I misspoke.

I think what I was trying to say is that my subjective impressions of listening sessions with a Lenco didn't match the subjective descriptions of yours and Art's. As far as stylus drag goes, I don't know whether or not that is perceptible. If it is, how would I know that was the reason for what I'm hearing?

 

[gusten]

Personally I have never seen any measurements that critically can be coupled with stylus drag, and I have done many measurements myself. It¨s not so easy so that more modulated groove will automatically create a higher force in a line to the pivot, and if it would be, that the platter inertia cannot cope with a higher intantaneous force.

We must realize that modulations mostly create vibrations, as the forces directions is pointing all over the place. I like to see some measurements that can stand some scruteny, but so far they are not there. I think it´s very important to see the whole picture of what can happen when vibrations are involved.
gusten

 

[marc mc]

If his subjective impressions were a dead on match for my own, I might give it some more merit but they aren't by a long shot.

I took this to mean that you have heard the L75 and did not hear what he says he hears, which BTW so many others have claimed to hear as well. Which is specifically an incredable cohesiveness of sound that is audibly the result of speed accuracy through the changing conditions and demands of a record, that can only be the result of the drive system. Because in many cases the drive system is the only thing used of the L75 after modding.

Can you or have you heard that with your ears while listening to that table, yes or no?

Marc mc

 

[Bigerik]

I took this to mean that you have heard the L75 and did not hear what he says he hears, which BTW so many others have claimed to hear as well. Which is specifically an incredable cohesiveness of sound that is audibly the result of speed accuracy through the changing conditions and demands of a record, that can only be the result of the drive system. Because in many cases the drive system is the only thing used of the L75 after modding.

Can you or have you heard that with your ears while listening to that table, yes or no?

Marc mc

A couple of good leaps in logic in that post, Marc. Just because a turntable has "an incredable cohesiveness of sound that is audibly the result of speed accuracy through the changing conditions and demands of a record" it does not necessarily follow that it "can only be the result of the drive system", or more correctly, a specific drive system.

Nor has it been proven anywhere that the "incredible cohesiveness of sound" is actually the "result of a speed system".

I've heard all of those things through many different drive systems.

 

[marc mc]

A couple of good leaps in logic in that post, Marc. Just because a turntable has "an incredable cohesiveness of sound that is audibly the result of speed accuracy through the changing conditions and demands of a record" it does not necessarily follow that it "can only be the result of the drive system", or more correctly, a specific drive system.

Nor has it been proven anywhere that the "incredible cohesiveness of sound" is actually the "result of a speed system".

I've heard all of those things through many different drive systems.

I have heard it from others as well. Like you I could post a list of tables I have heard that few on AK even know existed. But I really only want to know if Newman has or has not heard the cohesiveness with an L75 regardless of if he figures the source of it was the drive system or the name plate! Yes or no?

Marc mc

 

[dnewma04]

I took this to mean that you have heard the L75 and did not hear what he says he hears, which BTW so many others have claimed to hear as well.

What I did not hear was an L75 exceed the performance of all other tables I've heard. I heard a very good sounding turntable that I'd likely be very happy to live with.

Which is specifically an incredable cohesiveness of sound

This is the part where I start to veer. It sounded like a very good turntable, it didn't set any new standards to strive for.

that is audibly the result of speed accuracy through the changing conditions and demands of a record, that can only be the result of the drive system.

This is where you lose me. Not only do you state opinions/assumptions as fact, you go as far as to say your opinion/assumptions are the "ONLY" explanation for the subjective phenomena you are hearing. As one of my customers once said to me, "I call bullshit" (said for humorous effect not to be divisive).

Can you or have you heard that with your ears while listening to that table, yes or no?

Marc mc

I have heard a number of turntables that have sounded very coherent, cohesive, etc, using a number of different drive methods (including the L75, another model I don't recall and even the light plattered Bogen model). I'm not sure what else to add, the conversation seems to be going in circles. You and others have made a logical guess and assumed that you have defined some objective reason to explain your perceptions and it seems to have proven (to you) to be satisfactory. If that's good enough for you, I'm content in letting you continue feeling that way. It would be silly for me to tell you your opinion is wrong but you and Art make an unconvincing argument that it's right so I'm left still thinking that there is more to this than "ET".

Now I assume this is where you'll suggest that if I didn't hear clearly better cohesiveness than there must be something wrong with the implementations I've heard, my hearing, or something else that prevented me from hearing the obvious advantage, right?

 

[a.wayne]

"Harry told us that the wholesale cost of the motor to his factory is over $4000, so this is not going to be a cheap turntable."

It's commendable that VPI is endeavoring to improve speed stability with DD, but $4000 seems a bit steep. Curious to know what unit sales break-even point is for this table.

Damn he could have bought a BMW M motor instead ...

 

[dnewma04]

Personally I have never seen any measurements that critically can be coupled with stylus drag, and I have done many measurements myself. It¨s not so easy so that more modulated groove will automatically create a higher force in a line to the pivot, and if it would be, that the platter inertia cannot cope with a higher intantaneous force.

We must realize that modulations mostly create vibrations, as the forces directions is pointing all over the place. I like to see some measurements that can stand some scruteny, but so far they are not there. I think it´s very important to see the whole picture of what can happen when vibrations are involved.
gusten

One of my first thoughts a couple of years back when I first was pointed to Art's post was that if it were true, all hope would have been lost at the tape machine when it would have been unable to provide the "ET" to adequately plow through imprinting the signal onto the master tape during complex passages. Maybe Lenco made a tape machine that solved the issue? Or maybe only direct to disc recordings made on gear drive lathes are capable of producing a recording that would allow a Lenco to excel?

I'm being a bit facetious, of course, but this is the way my own elevator thinking works.

 

[a.wayne]

Personally I have never seen any measurements that critically can be coupled with stylus drag, and I have done many measurements myself. It¨s not so easy so that more modulated groove will automatically create a higher force in a line to the pivot, and if it would be, that the platter inertia cannot cope with a higher intantaneous force.

We must realize that modulations mostly create vibrations, as the forces directions is pointing all over the place. I like to see some measurements that can stand some scruteny, but so far they are not there. I think it´s very important to see the whole picture of what can happen when vibrations are involved.
gusten

Agree , do a coast down with needle in the groove and see how long the platter takes to come to a stop. Cant imagine losing speed with drive due to this drag ..

Would be interesting to see wow and flutter specs with cartridge drag.....

 

[Pio1980]

Agree, do a coast down with needle in the groove and see how long the platter takes to come to a stop. Cant imagine losing speed with drive due to this drag ..

Would be interesting to see wow and flutter specs with cartridge drag.....

Been done and referred to in previous threads, along with something about a costly flashing quartz-clocked LED thingie that rode the spindle and flashed a reference dot on the wall to show relative rotation rate drifting.

 

[marc mc]

Now I assume this is where you'll suggest that if I didn't hear clearly better cohesiveness than there must be something wrong with the implementations I've heard, my hearing, or something else that prevented me from hearing the obvious advantage, right?

No because we have both shared our findings and came to different conclusions. This is where we both quite wasting our breath.

Peace out

Marc mc

 

[a.wayne]

Been done and referred to in previous threads, along with something about a costly flashing quartz-clocked LED thingie that rode the spindle and flashed a reference dot on the wall to show relative rotation rate drifting.

Synopsis ......?

 

[totem]

Been done and referred to in previous threads, along with something about a costly flashing quartz-clocked LED thingie that rode the spindle and flashed a reference dot on the wall to show relative rotation rate drifting.

The LED thingie does differentiate between tables that can maintain exact speed and those that can not, whether this is of concern or audible is up to the individual to decide.

The number of TT that show steady speed with the led strobe are much
smaller than those that do, and caused considerable consternation to
certain $$ manufactures.

 

[a.wayne]

Ahhh , testing .......

 

[Bigerik]

The LED thingie does differentiate between tables that can maintain exact speed and those that can not, whether this is of concern or audible is up to the individual to decide.

The number of TT that show steady speed with the led strobe are much
smaller than those that do, and caused considerable consternation to
certain $$ manufactures.

Does it show if the speed is exact, or if it is more accurate?

Btw, can you post a link to these tests, please?

 

[Bigerik]

Ahhh. Listening.

Which is what the product this thread is actually about was designed for.

 

[fiddlefye]

Ahhh. Listening.

Which is what the product this thread is actually about was designed for.

Glad we came back to that part. I would love to hear one. Better yet would be to hear an example of each of their TOTL models of each drive type with the same arm, cart and electronics in close sequence. That would be interesting. I wonder if such a comparo will ever take place?