Peter, you are forgetting about nude. the vinyl just sitting on the platter without any clamping or weights. all my platters are straight so no concave to deal with. using a weight or clamp certainly does change the sound but not necessarily for the better imo - certainly no more information, just presented differently. Mostly I prefer the sound naked, but nice to have the choice.
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Peter, you are forgetting about nude. the vinyl just sitting on the platter without any clamping or weights. all my platters are straight so no concave to deal with. using a weight or clamp certainly does change the sound but not necessarily for the better imo - certainly no more information, just presented differently. Mostly I prefer the sound naked, but nice to have the choice.
You said "Certainly no vacuum hold at the best engineer in the world - Burnie Grundman. Neither does Kevin Gray or Sterling sound." on your OP. You made a claim and you need to prove it, not me. that's the logical way. But anyway I'll answer your question.
- In the first video you shared, there is a small puck on the spindle with a pipe. You can see it when the tape starts to roll, when the actual cutting starts. That's vacuum hold down and it's used by Bernie Grundman. Here is a photo of a Scully lathe (Bernie Grundman uses Scully). You can see small puck and a pipe over the spindle.
- Here is a photo of Neumann VMS 70 lathe with vacuum hold down. You didn't share a video about it but it is widely used so I didn't want to pass it. KG also uses VMS70. You can see the piping for vacuum hold down.
- In the second video you shared, RKS is operating a Neumann VMS 80 lathe. It is the latest model and the most improved one. Vacuum hold down pipe is moved underneath the platter as an improvement over VMS 70. Here is a photo of VMS 80 platter. There are holes for vacuum but there is no pipe over platter. That's why you can not see a pipe. Micro Seiki, Techdas, Bergman etc. use similar method.
- Additionally on both videos you shared both Bernie Grundman and RKS are cutting reference disks not master lacquers used for record manufacturing.
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I agree with you. I don't use a clamp or any other method. as I said on my earlier posts it provides equal pressure distribution like vacuum hold down. I don't know if this is better than other methods but I'm sure a washer and screw down clamp is not the best.
I once had the Pink Triangle Tarantella, which was not a great turntable overall but the platter was genius. It was dished a bit and in just such a way that records basically "sucked" themselves to it. No need for a clamp or vacuum hold down. If put your finger on the edge of the record it even resisted sliding. I suspect the shape made sure that there was good contact over the whole record and being a plastic platter it probably had sufficient electrostatic charge to give static hold down rather than vacuum hold down. Over such a large surface area that charge had a pretty good grip on the record. If the record had only been contacting at the edges (like if you have a flat platter with clamp or with a washer, then you won't get the same effect.
If all things are equal an increase in mass reduces vibration.
- Think about tweeters; designers try to decrease the mass of diaphragm IOT reach higher frequencies. Some diamond tweeters can reach 100kHz. If you switch the diaphragm with a paper one it can no longer produce 100kHz cause the same power can no longer move a heavier diaphragm (paper) as fast as lighter one (diamond). That is one aspect; high frequency vibrations are more absorbed when mass increases.
- Imagine you're doing push ups at every second and you can do 50 every morning. If 50kg of weight is placed over your shoulder and you try to do push ups every second like you used to do can you reach your maximum number 50? Certainly not. Same goes for mass too. If mass increases, same power can not move the higher mass at a certain frequency as high in level as lower mass. Level decreases due to shorter duration. That's the second aspect.
As a result if all things are equal when the mass increases:
- High frequency vibrations start to be absorbed more
- Low frequency vibrations decrease in level (duration). Both are a reduction of vibration in general.
In this case record shape, size and material are the same. Also disturbance introduced by turntable, motor etc to the record is the same. The only changing thing is the mass. So we can come to a conclusion that a 180g record has a lower vibration than a 100g record.
On the other hand the resonance frequency and it's relation with tonearm tube, bearings, cartridge suspension are more important IMHO.
Additionally older, lighter records are better cut, better pressed and made out of better material compared to new heavier ones IMHO. That is much more important than vibration decrease on record IMHO.
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Thanks for responding. I agree this object of discussion in not all that important relative to other factors. It started when I wondered about the notion that a thicker record vibrates less than a thinner record, regardless of how or whether it is fixed to the platter.
I am not a physicist, so bear with me. My understanding is that as mass increases the frequency of vibration decreases. Are you saying lowering frequency also lowers the magnitude or amplitude of vibration?
When we talk about 'reduced vibration' what talking about?
I am not a physicist either. Moreover English is a foreign language to me. I'll try my best.
Specifically for this case; an increase in mass results as an absorption on high frequencies and a reduction of amplitude on low frequencies. This is a reduction on vibration in total. The key point here is the power that causes confusion. The power is the disturbance introduced by platter, motor, speaker etc. The power or disturbance that causes vibration is same for both heavier and lighter records cause platter, motor etc are the same. That's why same power can only produce less movement (vibration) with higher mass.
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I understand the source of vibration -- the energy transferred into the vinyl comes from the table and external sources. Vinyl has its own natural resonance frequency. Clamp and vacuum create a tighter coupling between platter and record. Presumably the platter resonance should be well away from that to create a kind of impedance mis-match as it were.
Your English is quite good for whatever is your native tongue.
No Shane, I did not forget. Nor did I forget about the method spiritofmusic uses which is nude elevated on points. If you go back to my list, I mentioned the five methods I know to “couple” an LP to the platter. What you call nude I do not consider coupling. I tried it and preferred others. Personal choice.
Adam Gonsalves in this video clearly mentioned vacuum suction is used on the master plate.
Cutting a lacquer is a very different process than playback. I think vacuum hold down makes sense for cutting, not sure it does for playback. With a system like SAT’s, I wonder if there will be sufficient suction to flatten a warped disc? I have not read any detailed reviews of it, but it seems like a battery powered pump that is connected to flatten then disconnected before playback. Not very convenient, but it’s only about 40,000€ retail, so what can you expect
In full disclosure I am a SAT representative in Canada. I have a little bit of background information that I can add here regarding the SAT vacuum system.Cutting a lacquer is a very different process than playback. I think vacuum hold down makes sense for cutting, not sure it does for playback. With a system like SAT’s, I wonder if there will be sufficient suction to flatten a warped disc? I have not read any detailed reviews of it, but it seems like a battery powered pump that is connected to flatten then disconnected before playback. Not very convenient, but it’s only about 40,000€ retail, so what can you expect
The vacuum system is an option to the XD1 and can be purchased without it or with the typical threaded clamping system employed by many manufactures quite successfully.
The P1 (vacuum pump unit for the XD1) is not battery operated but is connected to the wall and has a PSU feeding the pump. The pump itself is a programable laboratory grade design rated at 30,000+ hours of continuous use. That is 3.6 million vacuum cycles on the XD1. It would be difficult to approach playing that many album sides in a lifetime. The vacuum hose is attached and detached from the valve port on the side of the platter. The hose is now brought through the body of the XD1 leaving a length available for easy connection. When you engage the vacuum system the P1 runs continuously until you reach the vacuum desired. You then turn it off and detach the hose. It does not run continuously or has permanent attachment as it was found that the continuous vacuum approach had a perceptible noise and detracted from the performance of the XD1. The convenience is secondary as the performance of the XD1 is of primary importance. The vacuum can last hours if left. More than enough time to play the entire album side. For disengaging the vacuum from the record there is now a button that is depressed. The early production unit provided a tool to release it.
We are also TechDAS and Dohmann dealers. The vacuum systems employed by TechDAS has had no issues with any warped records. It struggles with dished records, when the dished side is up as it does not contact the outer vacuum seals easily, but will easily flatten them with some coaxing around the edges.
In my experience vacuum systems add a level of performance to turntable designs and allow the majority of your records to be played flat, maximum contact to the platter surface and with a uniform pressure applied to the vinyl itself.
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Thank you. I appreciate the compliment.@JEB42 thanks for the info. Great lineup, the Toronto area surely benefits from such a great analog resource
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