TURNTABLE SETUP Questions thread - don't start a new thread, ASK YOUR QUESTION HERE!

[Gram2]

Thanks ,I know that there has to be a solid ground and some people say to put washers and mess around with the Pro-ject if it hums. To me I'm not one to buy one that hums and spend money to fix! 

 

[analogsurviver]

  Check this out:  https://www.youtube.com/watch?v=Aw2ifJFtERA&feature=youtu.be

Great result - better than most.
 
The reason why Rega used glass for the platter - if quality glass is selected, it is flatter than almost anything else in sheet form. Only requires making hole in the center and machining the circumference. All other materials require machining on all surfaces in order to achieve the same tolerances and the platter results in costing more.
 
Glass is not an ideal material for the platter - it is too "lively" and impedance mismatch with vinyl is great. That is why acrylic, delrin and simiar "plastic" are widely used now after pioneered for the TT use by the Pink Triangle. Rega itself later went as only of few ( Kyocera was the first IIRC ) with ceramic platters in their top models. At least the P7 platter I have seen and heard in action was impeccably machined.
 
However, adding a felt mat to use between the platter and record does not strike me as the best possible solution to the problem. Both for dimensional accuracy as well as for the resonance control.

 

[Eee Pee]

Never made sense to me why they'd boast about the glass platter but put a big piece of felt between it and the record.

 

[analogsurviver]

With Technics, it boils down to under how lucky star you were born : if VERY lucky, you might be having trouble even optically to tell whether the platter spins or is it stationary; if not :
 

 
I have seen similar but lessened in degree even in SP 10 Mk2 .

 

[analogsurviver]

  Never made sense to me why they'd boast about the glass platter but put a big piece of felt between it and the record.

$imple economic$. Ever since Linn discovered that felt mat sounded "better", the easiest and cheapest way out was to
use felt mat. It is light enough material that even if the hole is punctured considerably off center it will not introduce objectionable wow. Cheap material and cheap manufacturing can be used this way.
 
But when one wants to use anything else as mat, it is either precisely made  mould and/or machining each piece.
Depending on material, this can reach quite high figures. Mat is ALWAYS to be judged with specific platter(s)/material(s) - there is no such thing as an universally acceptable mat that could prove its superiority when used with each and any turntable. There are good examples of stock turntables whose mats were made so well that replacing the original mat with anything else will most likely result with decrease of SQ.

 

[Eee Pee]

I went from aluminum with a rubbery mat and no clamp to delrin and no mat with a screw down clamp.
 
I like my records flat and damped.
 

 

[analogsurviver]

  I went from aluminum with a rubbery mat and no clamp to delrin and no mat with a screw down clamp.
 
I like my records flat and damped.
 

It is the most reasonable solution without breaking the bank.
 
But one has to be aware that clamps (or weights) can do only so much - if the record is dished convexly (say on side A ), it helps in flattening the record by mating it to the platter surface, which also brings damping of both the record and the platter. 
If the record is dished concavely ( say on side B ), normal screw down clamp or weight will not only fail to flatten the record against the surface of the platter, but will lift it off the platter even further. This can be ( to a degree )  improved by using a washer around the spindle area between the mat and record and an appropriate clamp; this way, the entire record surface can be brought in contact with the mat . This solution was IIRC first introduced by Oracle.
 
Normal clamps or weights can well lift the perfectly flat record from the mat/platter - and therefore their use can well have detrimental results compared to flat record simply laying on the mat/platter. This is often seen mistake. If you look the junction made by the record and mat/platter from the profile; if you can see any gap between the record and mat/platter, whatever you are using (weight, clamp ) - is not good enough.
 
The record should be supported across entire playing surface for best sound. 

 

[Eee Pee]

This VPI platter uses a rubber washer around the spindle, and the clamp is cut so only the outermost edge is pressing against the record.  
 
So ideally, only the outermost edge of the record is touching the platter.  Works well I think.

 

[analogsurviver]

  This VPI platter uses a rubber washer around the spindle, and the clamp is cut so only the outermost edge is pressing against the record.  
 
So ideally, only the outermost edge of the record is touching the platter.  Works well I think.

Yes, it is one of the innumerable variations that came into being after first commercially introduced by Oracle. They differ in execution/complexity/cost, yet principle remains the same :
 

 

[analogsurviver]

  Thanks ,I know that there has to be a solid ground and some people say to put washers and mess around with the Pro-ject if it hums. To me I'm not one to buy one that hums and spend money to fix! 

I understand your position - but learning how to prevent hum in ANY turntable, not just Project goes a long way towards long term enjoyment of playing records. Sometimes, it is only oxidized part that still looks to be OK - and that can either have intermittent,  contact with too high resistance or no contact at all. There is nothing worse than a metal platter that is supposed to be grounded left "in the air" - such a TT will hum no matter what.
 
If everything else fails, the use of silver varnish used to repair ( among others ) car window heating elements on the spot that refuses giving solid electrical contact can save
the day. All you need to test the continuity is an ohmmeter or DMM that can be bought really cheaply.

 

[riffer]

I can't remember where I saw the information; but regarding the Pro-ject., I believe that there is either a new version, or one is coming, that incorporates a number of improvements to deal with the "hum" issue.  It might worth a wait and see to ensure all the old ones have worked their way through distribution channels.

 

[bbophead]

 

  This VPI platter uses a rubber washer around the spindle, and the clamp is cut so only the outermost edge is pressing against the record.  
 
So ideally, only the outermost edge of the record is touching the platter.  Works well I think.

Yes, it is one of the innumerable variations that came into being after first commercially introduced by Oracle. They differ in execution/complexity/cost, yet principle remains the same :
 

No thanks.  Seems like a lot of touching of the record with one's greasy thumb and fingers and also putting unnecessary stress on a sprung table's springs plus adding one more time consuming step before playing some music.  I'm glad I don't own that table and happy that I sold my Oracle.

 

[bbophead]

 

  Check this out:  https://www.youtube.com/watch?v=Aw2ifJFtERA&feature=youtu.be

Great result - better than most.
 
The reason why Rega used glass for the platter - if quality glass is selected, it is flatter than almost anything else in sheet form. Only requires making hole in the center and machining the circumference. All other materials require machining on all surfaces in order to achieve the same tolerances and the platter results in costing more.
 
Glass is not an ideal material for the platter - it is too "lively" and impedance mismatch with vinyl is great. That is why acrylic, delrin and simiar "plastic" are widely used now after pioneered for the TT use by the Pink Triangle. Rega itself later went as only of few ( Kyocera was the first IIRC ) with ceramic platters in their top models. At least the P7 platter I have seen and heard in action was impeccably machined.
 
However, adding a felt mat to use between the platter and record does not strike me as the best possible solution to the problem. Both for dimensional accuracy as well as for the resonance control.

I went with the delrin mod.  Less lively and no mat.  Some say it takes the life out of the music but I don't hear it that way.  Frank at Groovetracer does excellent work.  If I casually look to see if the table is running, I can be fooled.
 

 

[analogsurviver]

  I went with the delrin mod.  Less lively and no mat.  Some say it takes the life out of the music but I don't hear it that way.  Frank at Groovetracer does excellent work.  If I casually look to see if the table is running, I can be fooled.
 

I really like your take on the Rega - said it many times. It is the reasonable thing also in financial terms and perhaps sweet spot in all things Rega phono. 
 
That "live" feeling taken out of Linn, stock Rega, etc by non-resonant platters and without felt mats is a group of colourations people have gotten used to - and used as a trade mark. The turntable should be as dead as possible - no sound of its own. Comparison with master tape (or file ...)  is the only way to subjectively correctly judge the performance of a turntable. 
If the master is "dead", than I do not want my TT to make it "alive" - that is the task of recording engineer, producer, mastering... - NOT a turntable, which would anyway produce that "live feeling " in an "one note samba" fashion ( according to its mechanical resonances ). 
 
A really good TT (or anything else in audio ) is a rather boring thing at first listen - NOTHING special about it. Long term experience is another matter - as this "boring" piece of gear may well prove to be the most accurate and capable of displaying small shadings that make for the great artists  - and which would be lost by being burried below "live feeling" of a lesser TT.

 

[analogsurviver]

  No thanks.  Seems like a lot of touching of the record with one's greasy thumb and fingers and also putting unnecessary stress on a sprung table's springs plus adding one more time consuming step before playing some music.  I'm glad I don't own that table and happy that I sold my Oracle.

I can understand your position. 
 
Yet adding one more time consuming step before playing some music and  greasy fingers touching the record one way or another is the only way that can assure the record is supported under its entire playing surface by the mat/platter.
 
Unless going by the active vacuum suction turntable. That starts at roughly 4K$.