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My turntable has a very basic/simple power supply, namely an on/off switch, a 0.12uF/400V capacitor for phase shift, and a 220V ac 4 watt motor. I was wondering whether one of those uninterruptible power supplies that are used in computing and science labs would bring any benefits with regards to speed stability or motor noise, as our mains electricity supply can be prone to slight fluctuations due to our location out in the countryside? Please forgive me if it is a dumb question but I am not very clued up on electronics to know if it is a silly idea.
Follow Ups:
I have used various power cleaners and they have an effect but, the largest effect by far is from a source that has a very pure 60Hz sine wave(take a look on your oscilloscope.) a signal generator can help here.
If you don't want to do that. Then I suggest a a serious filter as it reduces noise in the motor(given noisy wall power) if you have a lot of grunge in the power line. The UPS might have a filter that works.
The third thing to use is a variac to reduce the voltage into the turntable as that will also reduce noise dramatically. 65-70v works great on an LP12.
"The third thing to use is a variac to reduce the voltage into the turntable as that will also reduce noise dramatically. 65-70v works great on an LP12."Bingo. I've had my table plugged into a pretty decent line conditioner with good results for many years but one of the bigger bang for buck tweaks I've experienced is running my AC Gyrodec off a variac after Harry Weisfeld from VPI suggested it here in a thread a year or two ago.
For $50 it is a no brainer on tables with an AC synchronous motor. Both the VPI SDS and Linn Lingo power supplies drop the voltage after startup to around 70 volts. With a variac you are going to have to do it manually so there will be an extra step involved in playing a record. Then again, a variable output transformer is $50 vs maybe 20X that for something like the SDS and Lingo, which clearly do a few other things and offer up 33/45 speed control as well.
I run my Gyro at 68 volts.
Edits: 06/01/12
The Project Speedbox SE II also looks interesting but, again, I am not certain it would work with my turntable. The ProJect has a 230v output on the rear panel but this output says it is for 3W power consumption max - am I right in thinking my 4 watt motor is therefore too high a draw on it? (as previously stated, apologies if that is a dumb question)
Assuming the answer to the above first question is 'no' and that it could therefore be used if no other incompatabilities, the Speedbox manual states that it is not designed for use with a "capacitive load". Is my turntable, with its 220c AC, 4 watt motor, and single capacitor for phase shift a "capacitive load"?
But the problem is how the typical computer UPS works. The typical UPS box has some filtering and surge protection that is applied to your household AC current but the regeneration part of the equation is not kicked in until the AC voltage drops below a certain threshold.The turntable boxes mentioned by another poster uses the same technology that a computer UPS uses when it kicks into regeneration mode but the turntable box runs like this full time. The computer UPS will not go into AC regeneration mode unless you lose AC power or it drops below a threshold.
The computer UPS concerns itself with providing clean power and uninterruptable power. It does so by charging its battery, filtering and passing along the AC power when that AC power is available and depending on its battery and AC regeneration circuitry to provide the AC power when the household power drops. Some computer UPSs do the filtering and surge suppression better than others but by design they allow less than perfect power through assuming that power is good enough to keep the average computer operational.
You are better off buying one of the turntable speed control boxes that are available. It will do the job you want full time.
Ed
We don't shush around here!
Life is analog...digital is just samples thereof
Edits: 05/29/12
Good point about the dedicated turntable motor speed controller but what about this idea....
How about a PS Audio P300 power regenerator? It takes AC in from your mains and regenerates it as a filtered and pure rock solid sinewave and you can even select the voltage and frequency output. If you choose 60Hz it stays at a rock solid 60Hz. Same for voltage. Choose your output voltage and it stays there regardless of how your AC mains are fluctuating (within reasonable limits).
Would this be a viable alternative to a TT motor speed controller? I think it might, unless the speed controller is somehow run in a 'closed loop' fashion where it adjusts based on a feedback signal from the motor, maybe in the form of a tachometer.
The whole reason i bought the PS Audio P600 was reading an article about 'alternate' Hz for the A/C power supply and how a faster HZ on the current gave more power available to the components power supply (as the power supply uses the peak mostly, so more peaks, more power)
I had to find one WITH the optional, no longer available HZ board.
I did aand am one happy camper.
I tried 75hz and 90 hz and am happiest with it set to 110hz.
But the SDS has additional features to control the speed at 45RPM plus the stylus timer thing.
The SDS would be optimized to work with VPI motors and I'm sure they tested it to make it generate the most motor friendly waveform possible. The other device's point is to produce a sinewave power waveform.
Its just the difference between the point of the devices and the convenience of the 45RPM thing.
Ed
We don't shush around here!
Life is analog...digital is just samples thereof
Thanks for the replies. I even understood most of them, which is great!So a UPS isn't ideal but there are other possibilities such as the PS Audio device mentioned and the turntable speed controllers listed.
Regarding turntable speed controllers, does anyone have any experience of the Heed Orbit 2? It is a relatively straightforward device that even I could fit (it only requires the replacement of the plug on your turntable), and claims to output a steady 230v AC (I am in the UK) and offer switchable 33/45rpm by altering the frequency between 50Hz and 67.5Hz. The PS Audio is available in the UK but I don't think the increments of frequency change would allow it to do 45rpm (unless I have misunderstood how it works), though this is not too much of an issue as 45rpm is achieved on my turntable by the changing of belt on pulley. The VPI SDS looks interesting but I don't think it would suit my turntable as it only outputs 115v.
How about something like this:
Edits: 05/30/12
The SDS made my VPI TNT Mk. II sound much better than using the P300 without the SDS. But this was many years ago. All are gone now.
Some Sondek owners with a Naim power supply use a PP300 to spin 45 rpm records with a 60hz Linn motor instead of futzing with changing a pully. ( PITA )
No comment regarding direct benefit to the turntable.
I do have two surge protectors, one outside the house, the other on the main circuit breaker panel. All of my audio & video gear is on a dedicated circuit in my studio, protected by a large UPS. This wasn't done for any audible improvement (and indeed I can't hear any) but rather as protection from surges, lightning strikes, and periodic black outs. I'm doing audio & video transfers for customers, so if the power goes out I can lose time and billable hours with a 'start over.' The UPS has paid for itself many times over.
Sorry. NT
Not a dumb question. I think what you're after is some kind of voltage stabilizer. However, that will not help if there is a mechanical or electromechanical problem with the actual table, as you know.
Having said that, I do use two APC Backups 550's (and power line filtering) for no other reason than my area is plagued with inexplicable blackouts, and even worse, brownouts.
What I'd like to get in addition to that is an AVS2000, which is a voltage stabilizer, to feed my gear with a steady 120VAC. I've measured the house voltage and it most definitely fluctuates.
Several turntables have a better power supply box available. VPI, Rega, Avid..
As for the AVD2000... Way better to just get a power conditioner.
I still have my Monster HTPS 7000SS though I do not use it.
I use a Furman REF20i and a PS Audio P600 for conditioning.
When i had the AVS2000 from Monster yeah it kept the voltage from fluctuating, but the few volts change from day to night just was not enough to be worth the downgrade in sound quality that came with it daisychained to a conditioner.
(alone it was not bad, but the conditioner alone on the A/C sounded better to me)
I sold the AVS2000 last year after it sat around for a few years.
If your voltage is not sagging or going too high, the variation of five volts is normal and not a problem.
Edits: 05/29/12
As a builder of tube amps, I have to hold fast that a voltage stabilizer, such as the AVS2000 (or any other well executed v.s.) is a good idea and will most likely extend the life of the component, all things considered.
Better power supplies/speed regualtors for the turntable itself (like an SDS, Speed Box, Paul Hynes PSU, etc. etc.) are also very good ideas if the aim is to get the most performance possible out of the deck. However, if the deck itself is shot (bad bearing, stretched belt, flat spotted idler) little else will matter.
By itself the AVs was not bad. but daisy chained to the regular conditioner it did degrade the sound.
And i liked the sound with the power conditioner more than the AVS.
So i dumped the AVS.
Ah, makes sense, I can see that as a possibility.
I'm always a little cautious, especially about placement, of these devices. These UPS' are really built for PCs/servers/etc. If APC has made any claims about being audiophile grade, I've not seen them. Monster, of course, is *supposed* to be audiophile grade. Considering what you've said, I think I'll try to arrange a trial before actually purchasing one.
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