New OMA turntable

[TLi]

Clamp down and suction are fundamentally different concepts.

Clamp down is to press the edge of record to the platter from the centre and tries to flatten the LP. It did very little to reduce the vibration of record surface. When a record is played, the whole vinyl surface vibrates with the music. The record is actually like the skin of a drum. It resonates and smears the sound. That’s why 180g records usually sounds better because the thicker layer of vinyl reduces resonance.

Suction presses the whole record tight onto platter, the record surface resonance is much reduced. Every record becomes 200g or 300g record. The resolution is enhanced. So it is not just flattening of record, the vibration control is also vital.

 

[bonzo75]

If Weiss outsources everything to experts, he should just hire Romy for the bashing

 

[tima]

That’s why 180g records usually sounds better because the thicker layer of vinyl reduces resonance.

I suspect there is no less resonance with thicker vinyl. It just changes the frequency at which it resonates.

 

[XV-1]

Clamp down and suction are fundamentally different concepts.

Clamp down is to press the edge of record to the platter from the centre and tries to flatten the LP. It did very little to reduce the vibration of record surface. When a record is played, the whole vinyl surface vibrates with the music. The record is actually like the skin of a drum. It resonates and smears the sound. That’s why 180g records usually sounds better because the thicker layer of vinyl reduces resonance.

Suction presses the whole record tight onto platter, the record surface resonance is much reduced. Every record becomes 200g or 300g record. The resolution is enhanced. So it is not just flattening of record, the vibration control is also vital.

With respect, I think you are clutching at totally unproven aspects of vinyl reproduction to justify vacuum hold.

The stylus doesn't care how thick vinyl is.

As Tim said, the difference in record thickness just changes the resonance at which it resonates.

There is no vacuum hold when vinyl is being cut.

 

[TLi]

With respect, I think you are clutching at totally unproven aspects of vinyl reproduction to justify vacuum hold.

The stylus doesn't care how thick vinyl is.

As Tim said, the difference in record thickness just changes the resonance at which it resonates.

There is no vacuum hold when vinyl is being cut.

As far as I know, master disc is cut with vacuum hold down. Correct me if I am wrong.

The stylus acts like a microphone to pickup all vibrations on the record. Thinner record will vibrates more than thicker ones. A drum with thick skin is not going to be as loud as a thin skin one.

 

[tima]

The way I think about this is a clamp or vacuum hold-down couples the record to the platter. It is the combination of materials that determines the resonance frequency of they vinyl. Different platter material will also impact resonance frequency. Vacuum hold-down may make for a more effective coupling - that, along with flattening, is the argument for vacuum.

Resonance reduction is simply the transfer or movement of energy -- everything vibrates, resonates at some frequency. I don't see a reason that thicker vinyl resonates any more or less than thinner vinyl, but they may vibrate at different frequencies. Those different frequencies may affect how the stylus responds -- how energy may impact the stylus movement or get transferred into the cartridge motor as energy not coming from the stylus movement alone.

As to drums... I do not believe a thick drum skin causes a louder sound than a thin drum skin. I believe loudness comes from the force at which the drum is struck and the type of stick that is used to strike it. The drum skin thickness may correlate with the pitch of the drum as will the type of stick used. Large drums such as bass drum and timpani can sound louder at lower frequency because they have a greater skin surface area and move more air. A snare drum will cut through an orchestra because it has a higher pitch. Skin tightness affects pitch as does drum skin coating.

 

[XV-1]

As far as I know, master disc is cut with vacuum hold down. Correct me if I am wrong.

The stylus acts like a microphone to pickup all vibrations on the record. Thinner rec

rd will vibrates more than thicker ones. A drum with thick skin is not going to be as loud as a thin skin one.

Certainly no vacuum hold at the best engineer in the world - Burnie Grundman. Neither does Kevin Gray or Sterling sound.

Disagree that thinner vinyl vibrates more than thicker.

 

[mtemur]

With respect, I think you are clutching at totally unproven aspects of vinyl reproduction to justify vacuum hold.

I don’t know what to say cause it’s so wrong. I’m trying to identify pros and cons of every method with my limited knowledge and trying to improve my knowledge by discussing.

The stylus doesn't care how thick vinyl is.

The argument is not about the thickness of record but effectiveness of different coupling methods between record and platter. “Thickness of record” or more accurately “mass of record” of course has impact on final sound but that doesn't mean 180g is better. It’s a complicated subject.

As Tim said, the difference in record thickness just changes the resonance at which it resonates.

Both @tima and @TLi are right. When a thicker record is screwed down with a washer both level of resonance in general and resonance frequency decrease due to higher mass. Resonance frequency is more important here.

There is no vacuum hold when vinyl is being cut.

There is vacuum hold down while cutting a lacquer. It’s an absolute fact and even Weiss accepts it.

 

[mtemur]

Suction presses the whole record tight onto platter, the record surface resonance is much reduced. Every record becomes 200g or 300g record.

Actually it’s much more. A record under absolute vacuum couples to the platter with a weight around 97kg (97.000g) far more than 200-300g. An absolute vacuum is hard to achieve that’s why this figure will be lower than 97kg. Maybe 80 or 70kg I don’t know but still much higher than any other method can do. Most important thing here is pressure spreads over the record surface uniformly . No other method can achieve uniform pressure. Actually there’s another method achieves uniform pressure over record surface, “nothing method”. Using no clamp, washer, outer ring etc is the only other method guarantees uniform pressure over record surface besides vacuum hold down but it has it’s own disadvantages.

 

[Solypsa]

Many lathes through the early history of the process did not have vacuum hold down. The Neumann VMS 70, such as the one I owned, was designed to use vacuum hold down. Mine as it happens was setup by a tech that maintained Sterling Sound lathes through the 80s and early 90s. He advised me to use it.

A master lacquer is a metal disc coated in cellulose and not vinyl anyway, so this is not a simple comparison.

 

[PeterA]

I know of five ways to couple a record to the platter: Vacuum hold down, clamp with washer, clamp without washer, record weight on flat platter, record weight on concave platter. There is also the matter of using a mat and what surface material and texture there is on the platter.

I have lived with at least three of these methods. My SME turntable had a screw down clamp and washer system on a platter with a scrolled soft vinyl like material adhered to it. That resulted in a very damped sound. It seemed very good at reducing residence from the vinyl. It was inconvenient to have to shut down the platter each time and unscrew the clamp. The clamp pressure also affected the sound and the coupling of the inner part of the record to the platter. This resulted in some inconsistency and inconvenience

I then had vacuum hold down with a leather felt mat on a stainless steal platter on my Micro Seiki SX 8000 II. I was told that in this case the vacuum hold down what is a solution necessary to stop the ringing of the platter. In this case the vacuum hold down was used to dampen the effect of the platter material. Of course it also resulted in a very good coupling between the record and the platter but it was sometimes difficult to get the edge of the record and vacuum seal really tight. The sound was very neutral to my ears.

I now have a heavy record weight, a smooth leather mat on a concave extremely massive 150 pound platter. There is a thinner upper platter of a different type of metal that is non-magnetic because the machining of the slight concave surface magnetizes the the stainless steel. I think this in parts a consistent level of pressure along the record surface as does vacuum hold down. This solution is as effective as the vacuum and sounds as neutral but is much more convenient and far more simple, so it is no easy task to machine the surface of the platter. I leave the platter spinning all day and simply lift the record weight and flip the record.

Of course many factors contribute to the overall sound of the turntable. One wants a good neutral interface between the record and the platter and there are many possible solutions. Much of it comes down to quality of the implementation but materials and convenience or ease of use is also a factor.

My favorite of the three methods I have lived with is what I use now, the heavy record weight on a leather mat with a very slight concave platter surface.

Jonathan Weiss chose his platter material, clamp and washer system for specific reasons but, IMO, it is not accurate to say that it is the best solution available. It may be the easiest to design and implement.

 

[mtemur]

Certainly no vacuum hold at the best engineer in the world - Burnie Grundman. Neither does Kevin Gray or Sterling sound.

Disagree that thinner vinyl vibrates more than thicker.

I watched the videos again. There is nothing mentioned about vacuum hold down. How did you get the impression that they don’t use vacuum hold down?

 

[tima]

When a thicker record is screwed down with a washer both level of resonance in general and resonance frequency decrease due to higher mass.

I'd like more information. Are you saying 'more mass' in terms of a, for example, 160 gram LP versus a 180 gram LP?

I can understand a change in resonance frequency, but am sceptical about the amount of resonance being reduced. Would you please explain?

 

[PeterA]

I'd like more information. Are you saying 'more mass' in terms of a, for example, 160 gram LP versus a 180 gram LP?

I can understand a change in resonance frequency, but am sceptical about the amount of resonance being reduced. Would you please explain?

I have a theory Tim even though I am not making the claim. When I had my SME turntable I noticed that I had to screw down the clamp tighter with a thicker record or there remained a gap under the inner third of the record. Thinner records are more flexible generally, and they conformed to the platter surface with less clamp pressure and the coupling was often more complete. With the SME damping material on the platter surface, the record was deader or more damped when there was more contact with the material. The contact at the outer edge of the record was usually better.

this variability is not an issue with the vacuum hold of the micro Seki turntable or the American sound turntable I now have.

 

[tima]

I have a theory Tim even though I am not making the claim. When I had my SME turntable I noticed that I had to screw down the clamp tighter with a thicker record or there remained a gap under the inner third of the record. Thinner records are more flexible generally, and they conformed to the platter surface with less clamp pressure and the coupling was often more complete. With the SME damping material on the platter surface, the record was deader or more damped when there was more contact with the material. The contact at the outer edge of the record was usually better.

this variability is not an issue with the vacuum hold of the micro Seki turntable or the American sound turntable I now have.

I understand you to say a clamped thinner record is deader or more damped than a thicker record.

Here is my thinking ... 'deader' or 'more damped' translates to lower resonance frequency. The idea being to shift the resonance frequency of the vinyl to something that is inaudible to our ears. Or put differently, shift the resonance frequency of the record to reduce audible distortion at the creation of the source signal.

When vibration is put upon a thing at that thing's own natural resonance frequency the resonance of the thing increases. So moving the vinyl+platter resonance frequency well above or below the natural resonance frequency of the cartridge is a positive.

 

[XV-1]

I watched the videos again. There is nothing mentioned about vacuum hold down. How did you get the impression that they don’t use vacuum hold down?

Exactly. Can you see vacuum hold being applied anywhere?

 

[PeterA]

I understand you to say a clamped thinner record is deader or more damped than a thicker record.

Here is my thinking ... 'deader' or 'more damped' translates to lower resonance frequency. The idea being to shift the resonance frequency of the vinyl to something that is inaudible to our ears. Or put differently, shift the resonance frequency of the record to reduce audible distortion at the creation of the source signal.

When vibration is put upon a thing at that thing's own natural resonance frequency the resonance of the thing increases. So moving the vinyl+platter resonance frequency well above or below the natural resonance frequency of the cartridge is a positive.

Tim, it was easier to make a good contact with a thin record against the dampening material on the SME platter. It could still be done with a thicker record, one just has to apply more clamping pressure. If I got good clamping pressure with both then the thicker record generally tended to sound a little more damped.

I don’t know if that was vinyl formulation or thickness or what. Anyway, this was my least favorite of the three clamping methods I have used in the last 10 or so years.

 

[microstrip]

(...) Jonathan Weiss chose his platter material, clamp and washer system for specific reasons but, IMO, it is not accurate to say that it is the best solution available. It may be the easiest to design and implement.

Still thinking there is a best in vinyl playback? It is probably the solution he prefers sonically. If people also prefer it, they should be happy. Others will surely prefer otherwise.

In my turntable I prefer vacuum on - closer the sound I get from my other reference sources.

Can you imagine how good it would sound an LP in which only one side was grooved and the other was flat? I know the experiment was tried decades ago, but do not remember the results.

 

[Bonesy Jonesy]

I remember reading that Franc Kuzma with the Kuzma XL DC TT preferred the non screw down Kuzma Ebony Spindle Clamp with no spindle washers and with the Kuzma Outer Ring Clamp vs the Brass screw down with spindle washers that come with the XL DC and with and without the Kuzma Outer Ring Clamp !

 

[Solypsa]

Can you imagine how good it would sound an LP in which only one side was grooved and the other was flat? I know the experiment was tried decades ago, but do not remember the results.

I too don't remember any consensus or measured testing but these type of discs are not too difficult to find if you rummage through some bins of techno 12" . I have a few...