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Post by Deleted on Jun 14, 2020 18:33:54 GMT
I've just bought an original Rega P2 for a second system and have bought a 24v motor, aluminium sub platter, Delrin main platter and a Peek ceramic bearing. I'm also going to try to isolate the motor by setting it in a sub plinth sited beneath the deck a bit like the SRM Silent Base. I've just bought a P1 gloss black plinth for £22 on eBay to use as the sub plinth and like the SRM I will isolate and separate the two plinths with 4 sorbothane domes. The P1 plinth is used and so already has a section cut out for the motor to sit in. The plinth below is from a Nimak Rega modified deck from Croatia I think that shows the kind of thing I'm thinking of and below that is the P1 plinth I've bought. Has anyone tried this mod or have any ideas advice that might be helpful below is a link from someone who fitted an SRM Base to give you an idea. www.vinylengine.com/turntable_forum/viewtopic.php?t=73056 s-l1600 by [a href="https://www.flickr.com/photos/141362658@N06/"  s-l1600 by
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Post by sq225917 on Jun 14, 2020 19:14:57 GMT
I did a p5 years ago. The lowest noise was from routing out a square of the plinth, right through. And then bolting the motor to a sheet of carbon plywood carbon laminate sheet and then damping between them with 2mm of sorbothane sheet cut as a 1cm outline of the overlap between hole and plate. The sorbothane was sticky enough to stop the motor moving, but soft enough to absorb vibration.
Just set the motor to compensate for the 5mm stack height of the new set up.
Tried plain Carson sheet 2mm thick, it was noisier than the ply carbon plate. It's called Dragonplate.
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Post by Deleted on Jun 15, 2020 6:02:47 GMT
I did a p5 years ago. The lowest noise was from routing out a square of the plinth, right through. And then bolting the motor to a sheet of carbon plywood carbon laminate sheet and then damping between them with 2mm of sorbothane sheet cut as a 1cm outline of the overlap between hole and plate. The sorbothane was sticky enough to stop the motor moving, but soft enough to absorb vibration. Just set the motor to compensate for the 5mm stack height of the new set up. Tried plain Carson sheet 2mm thick, it was noisier than the ply carbon plate. It's called Dragonplate. Thanks very good advice as soon as I start putting the deck together I'll post some pictures. SRM do something they call a Motor Vibration absorber which is made of a polymer and helps to hold the motor implace it looks like a big grommet with a notch cut out for the wires. |
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Post by sq225917 on Jun 15, 2020 12:40:33 GMT
Their stuff is generally well made.
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Post by dsjr on Jun 15, 2020 16:46:06 GMT
I may be totally wrong now, but it's my experience that the only way to quieten down an Aipax style motor is to reduce the driving voltage and carefully optimise the phase shift driving the motor coils.
Of course the 24V version may be rather different here, but my RP3 'Mule deck' with 24V motor still suffers motor drone getting into the stylus (admittedly using an R200 arm which isn't really suited to the later decks imo). I believe that's what the external power supply aimed to diminish as the 'phasing' could be better optimised. The Neo supply adds fine speed adjustment which in my experience almost ALL Regas need as most run slightly fast without this adjustment option, the white belt making it worse!
If the above is irrelevant, then I apologise. I tried a good size 24VAC transformer with the above deck, didn't like the sound much to my liking and the deck now sits sulking in the loft.
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Post by Deleted on Jun 15, 2020 18:23:14 GMT
I will eventually trade up from TTPSU Mk2 to a Neo but I bought both platters and a new 24v motor so there was no cash left for a Neo at present. I'm not saying this mod will remove all noise caused by motor vibration getting to the stylus but removing the motor from the same piece of wood that holds the tonearm must have a positive effect and then adding further isolation by putting three or four sorbothane domes between the piece of wood holding the motor and the piece of wood holding the tonearm must also help matters.
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Post by sq225917 on Jun 15, 2020 20:16:07 GMT
The 24v motors are quieter than the 110v premotec, but cogging is the same. Accurately setting phase offset to your specific motor is key to low drive noise.
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Post by Deleted on Jun 20, 2020 8:05:43 GMT
I've been looking more at the SRM Tech Silent Base which is a kit which makes this mod extremely simple and for the money £129 looks like pretty good value baring in mind I'd have to buy new feet and the motor vibration absorber which both come included.
Also apart from another bearing and a tonearm I actually have two decks so I may build another bedroom deck to use with a headphone amp or sell the parts to recoup some of the outlay.
I contacted SRM yesterday and they have a small batch of the black Silent Bases coming in at the end of June so I reserved one.
I'll resurrect the thread as soon as it arrives and post pictures then.
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Post by sq225917 on Jun 20, 2020 12:50:03 GMT
If I was doing a rega deck these days I'd wrap the motor body in 10mm neoprene rubber and mount it in a circular heavy metal sleeve with rubber feet.
The neoprene will damp almost all vibration while still providing total geometric stability so the pulley never moves relative to bearing/sub.
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Post by Deleted on Jun 21, 2020 20:53:33 GMT
I may be totally wrong now, but it's my experience that the only way to quieten down an Aipax style motor is to reduce the driving voltage and carefully optimise the phase shift driving the motor coils. Of course the 24V version may be rather different here, but my RP3 'Mule deck' with 24V motor still suffers motor drone getting into the stylus (admittedly using an R200 arm which isn't really suited to the later decks imo). I believe that's what the external power supply aimed to diminish as the 'phasing' could be better optimised. The Neo supply adds fine speed adjustment which in my experience almost ALL Regas need as most run slightly fast without this adjustment option, the white belt making it worse! If the above is irrelevant, then I apologise. I tried a good size 24VAC transformer with the above deck, didn't like the sound much to my liking and the deck now sits sulking in the loft. I have been looking into this method dsj and it seems you are onto something after all so thank you and forgive my ignorance it also looks like quite an easy thing to do reducing motor hum if successful will mean that the motor isolation mod might not be needed! I was even considering buying the SRM Silent Base so the saving will mean I could sell my TTPSU 2 and put the funds to a Neo. |
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Post by Deleted on Jun 22, 2020 19:00:34 GMT
I've actually gone through the first part of the method , first take the belt off then replace the platter put a record on and place the stylus on to the record somewhere near the end close to the motor then switch the power on so that the motor is driving the pulley without the belt attached then slowly increase the volume.
I found that I had no hum at all until the dial was almost on full and even then the hum was very low.
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