SDS or phono stage

Thanks Bpoletti.

The Herron phono stage is wonderful. Enjoy your investment.

Thanks Rodman99999!

Enjoy your music!

So, I have the SDS and got a Herron VTPH-2 last week. The Herron is still breaking in, but already sounds excellent. So far so good!

I spoke with Matt at VPI today, and he says it doesn't really matter how you do it. He says he has seen his father (Harry) leave it turned on for weeks at a time, using the tt motor switch. There is no harm in doing this, apparently.

Never mind I found it.

Here it is:
http://vpiindustries.com/manuals/CALIBRATION_MODE_FOR%20_SDS.pdf

Brf-

I don't mean to hijack this thread but...

What is the SDS "run hours" feature? I bought my SDS used and did not know this feature existed.

How do you reset it? How do you "read" its results.

Thanks.

Good idea, for those that track cartridge/stylus hours.

I use the on/off button on the TT as I find it more convenient to use. I spoke with VPI and they told me that there was no problem doing it that way. VPI says not to have the SDS too close to the TT. When I had it about six inches away it created some hum. I have them about three feet apart now and no hum at all. I have a newer Classic 3 with the motor in the rear which is a pain to change the belt. The SDS makes changing from 33 1/3 to 45 easy with the push of a button.

If you use the SDS’s on/off to control the motor, you can use the VPI SDS “run hours” feature to monitor cartridge use.

I've had a SDS in continuous use for 10+ years using the on/off switch w/o any problems.

Use the TT's switch and watch voltage display on your powered-up SDS. You'll notice that the drive senses start-up voltage requirement and provides it, then reduces again(your, "specified power sequence"). Just a BTW; I always start the platter and clean my LPs at 45rpm(more torque).

Gpgr4blu, that "VPI rep" is wrong. The VPI SDS is a motor controller and is used to turn the motor on and off with a specified power sequence.

The SDS manual states

Both the SDS and the turntable plugged into it may be turned on and off with the SDS's power switch.

Contact VPI if in doubt.

Thank you Gpgr4blu.

I was instructed by a VPI rep to always turn the motor on and off and not to use the sds as an on/off switch. That advise was many years ago but I think it still holds.

Thanks. When I was setting it up, I watched the sds as I turned the motor off and on. When I turned the motor on, the sds voltage jumped to 115 then down to 72, as I gather it should. Do you really switch the sds on and off every time you flip the record, brush it clean, etc?

Motor always on, and use the SDS to control the on/off. If you do it the other way, the SDS will not start at full power and then ramp down.

Thanks again. I hooked up my sds and set speed using the kAB. Question: do you leave the sds on all the time and turn the turntable motor on and off, OR do you leave the tt motor on all the time and use the sds to turn it on and off? Thanks again.

At least now I know that I can blame autocorrect for converting my moniker to "Lewn". No one should think I am at all angry about it. It's been happening ever since I started posting under "LewM" on Audiogon. I find it amusing, in fact.

Arsh, from all I have ever read about it (and that's all I know about it) the Herron phono stage you have purchased will likely make you very happy for years to come. I think you've made a good choice.

Thanks, Al.

Thanks everyone for the useful information. I got a bit of an education there. Mcbuddah, thanks for the tip about the ECPA. I had not previously heard of it.

02-26-14: Lewm
So an autoformer will not either block noise on the AC line or prevent tt motor noise from going back into the AC line. (I think this is true; perhaps Al will jump in and correct me, if I am wrong.)

02-26-14: Mcbuddah
All the variacs I have ever used or even seen have been of below par construction for audio use. I think most are used to control motors in certain kinds of factory production and OEM usaes in the same role, where critical adjustments are either not necessary or are supported with gauges or a servo mechanism. The speed precision needed to properly replay records far more important due to the sensitivity of our ears to even tiny speed inaccuracies. The KAB device used with VPI's SDS is capable of both setting and holding the speed steady, something else that the Variac likely does poorly in that it is set by mechanical means, whereas the SDS resolves in .01hz increments.

A Variac will provide some degree of filtering of high frequency noise, both ingoing and outgoing. The ability of noise currents to flow in response to noise voltages appearing between the AC "hot" line and either the neutral or safety ground lines will be constrained to some degree by the bandwidth limitations of the Variac, that limitation resulting mainly from the various inductive reactances that are present in an autoformer (or a transformer). The likelihood of that noise reduction being audibly beneficial in a given turntable application is anyone's guess, but personally I wouldn't bet on it.

Variacs are widely used in or in conjunction with test equipment for many electrical and electronic products, where testing requires precise setting and/or variability of the applied AC voltage. As everyone seems to realize, a Variac cannot change the AC frequency, as an SDS or other regenerator can, it can just vary the voltage. But, consistent with the posts by Bpoletti and Hdm, I would by no means categorically rule out the possibility of their being useful in some audio system applications. The leading exception to that being that I suspect their bandwidth limitations would make them unsuitable for use with power amplifiers or other components whose current draw fluctuates widely and rapidly.

Regards,
-- Al

The VPI SDS also reduces the voltage once the platter is up to speed. The end user can program the final run voltage.

Variac works quite well in my experience with my Gyrodec. It's a fairly serious bang for the buck as far as I'm concerned. No ability to control speed (as far as switching from 33 to 45 RPM) and it lacks the elegance and automation of supplies like the SDS but certainly no drawbacks in terms of holding actual speed.

Granted, the SDS probably does more (and should at the price) but HW is actually on record as recommending the use of a variac with certain AC Synchronous motors and the fact is that the variac does accomplish some of what power supplies like the SDS and Lingo do, namely reducing the voltage and, as a result considerably reducing motor noise/vibration resulting in a cleaned up presentation and lower noise floor.

Lewm, sorry about the typo. My iPad autocorrects Lewm to Lewn.

I have both the KAB strobe and PlatterSpeed app and Adjust+ disc. I found the platterSpeed to be more accurate and easier to use.

http://platterspeed.com/

Arsh, if you are still looking for a tube phono stage in the $1500 range, you might want to check out the Eddie Current ECPA. This is the same Eddie Current that makes the Zana Deux (and a lot of other) outre-quality headphone amps. The build quality and design quality of their products is extraordinary, and the designer/owner is tube audio legend. I am happy with a 15 year-old Thor in my system, but if it ever needs replacing, I would put the ECPA at the top of my list to audition. Please note that I have no financial interest in that company, just a very happy Zana Deux ZDT owner who has a real appreciation for the work product of fanatics.

Lew M, sometimes it is better to ask questions than to shout out answers, only to find out the world has moved on. All the variacs I have ever used or even seen have been of below par construction for audio use. I think most are used to control motors in certain kinds of factory production and OEM usaes in the same role, where critical adjustments are either not necessary or are supported with gauges or a servo mechanism. The speed precision needed to properly replay records far more important due to the sensitivity of our ears to even tiny speed inaccuracies. The KAB device used with VPI's SDS is capable of both setting and holding the speed steady, something else that the Variac likely does poorly in that it is set by mechanical means, whereas the SDS resolves in .01hz increments.

Mcbuddah, The SDS and the Variac are not equivalent devices, as you seem to know; the SDS is an active device whereas the Variac is passive. One small error: the Variac is an autoformer, not a true transformer. Since the primary and secondary of an autoformer have one connection in common, an autoformer does not isolate the primary side from the secondary. So an autoformer will not either block noise on the AC line or prevent tt motor noise from going back into the AC line. (I think this is true; perhaps Al will jump in and correct me, if I am wrong.) On the other hand, the SDS synthesizes "new" AC and both voltage and frequency can be varied. So the SDS can control a motor by varying either of the two parameters and will ameliorate noise, etc. I have a feeling you know all this. Bottom line: I have tried using a Variac, not to control a tt but to reduce bias voltage on an ESL panel, to "rest" the diaphragms when the speakers were not in use. For some reason, I found that it introduced a very objectionable coloration to the sound from the speakers. I don't know whether the same effect would be audible if Variac is used on a tt motor, but my Variac is now occupying a dark and dingy place in my basement.

Brf, What is "Platter Speed"? Since I've spent about ~$100 on the KAB Strobe, why would I want to spend $35 more on a device that does the same thing, or does it? By the way, that's "Lew M". You are not the only one who finds it hard to read "Lewm" and thus calls me "Lewn". On the other hand, I am a bit Lewnie, for sure.

Has anyone actually compared the sonic output of a variac vs. the SDS? From what I have read technically, the SDS is designed to control the speed of the motor by varying the FREQUENCY of the AC current where a variac is just a glorified transformer outfitted with a wiper to adjust the voltage by adjusting the effective number turns in the secondary.

I owned both the Walker and SDS and I could not tell any difference between the 2 units. I sold the Walker only because I had a friend who wanted it. I would have been happy with either.

Lewn, have you tried the Platter Speed? At a cost of $35, it is easy to use and hard to beat.

Just for the record, and speaking only for myself, I discussed the SDS only because that is the unit that Arsh asked about. What I said about the SDS is only hearsay. I personally do use a Walker Audio Precision Motor Controller, which does pretty much the same thing as the SDS but without some of the less useful SDS features. All my experience of the beneficial effects of a Motor Controller has to do with the Walker. Some, who have tried both the Walker and the SDS, have found the Walker to "sound" a bit better, but with a VPI tt, I assume the SDS would be a great match. There is no savings associated with purchasing the Walker vs the SDS. Used or new, I think the typical prices are about the same.

As to use of a laser tach and other similar gadgets, that's fine, but they do not address the issues at hand, and they suck up funds otherwise available for the nitty gritty solutions. The KAB strobe is the most accurate and cost-effective device for checking tt speed and speed stability, IMO.

To measure correct speed, purchase Dr. Feickert Analogue's Adjust+ tesy disc and download the PlatterSpeed app for iPhone, iPad and/or Android smart phones.

+1 for the SDS followed closely with a new phono stage.

Thanks.

This is the LASER tach that I chose: (http://www.amazon.com/Industrial-Grade-5URH0-Contact-Tachometer/dp/B004ZRN7AE/ref=sr_1_fkmr1_1?ie=UTF8&qid=1393294097&sr=8-1-fkmr1&keywords=5urh0+uni-t) There are many cheaper: (http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=laser+tach+uni-t&rh=i%3Aaps%2Ck%3Alaser+tach+uni-t) I also confirm my adjustments/speeds with the SDS strobe disk.

Arsh, i purchased a Digital Photo Tachometer Model: DT-2234C+. There were a bunch of sellers.

Thanks. Mcgal, what is that digital tack from Amazon?

Get a nice tube phono preamp like the Croft Acoustics RIAA for $995.

I find the strobe disk a little hard to read with my old eyes. Using a digital tack from Amazon for only $16.00 makes it easy for the fine adjustments that the SDS is capable of.

Thanks for your reponses. Is the strobe disc that comes with the SDS good enough?

Thanks a lot. I am getting a new VTPH-2 directly from Keith. I am excited to hear it!

I have the VTPH-1MC and I can't imagine a better phono stage and I've spent thousands in the past.... and everyone says VTPH2 is better. You'll love it and Keith is a fantastic person and very helpful. If it's used, have him go through it if you decide to buy. It's incredibly reasonable and you end up with basically a refurbished unit.

Herron phono stage plus a variac for the Scoutmaster. The Herron will take care of the cartridge (few , if any, equal or better), the variac will reduce noise from the table.

Variac operation is easy. Dial up 120v to get the table running and to brush the record surface, then reduce the voltage to 60v to 70v before playing the record.

The Herron is one I would like to hear. From all reports it should be a big improvement on your in built MF phono stage.

Thanks a lot everyone. I found an SDS here and have purchased it. Should arrive in a few days. I have also ordered a Herron VTPH2 phono stage for audition. Anyone have experience with it? Everything I have read has been very positive, and Herron is close to home. Thanks again for your help.

The phono stage in the MF A308 integrated I had long ago was not very good. Not sure how it compares with your newer MF though.

It will depend on how much your budget is? If you could stretch for something like a Parasound JC3, it would be more of an improvement than the SDS alone. If your budget is around $1k then it becomes a closer call. Personally I would save as much as possible and get a really nice phono stage first.

Correct! The SDS converts wall AC into DC, then synthesizes AC, at whatever(user adjustable) frequency it takes to achieve 33 1/3 or 45 rpm. It also lowers the voltage, after platter start-up, to reduce motor noise. I like not having to change the belt, to go from 33 1/3 to 45 rpm. That now just takes the push of a button.

what about using the cheaper alternatives to the SDS that correctly maintain speed?

Arsh (and Lwin), The SDS is an AC re-generator. Think of it as an amplifier that puts out 120V and 60Hz (or whatever variation from those baseline parameters is needed to make your tt run at precise 33 and 45). Thus it does more than any typical power conditioner, most of which are just noise filters with or without an isolation transformer, unless your power conditioner is also an AC regenerator. Lwin, your balanced AC power does not substitute for the SDS or other similar power regenerating motor controller. Moreover, a good motor controller also makes the tt motor run quieter, if properly adjusted. Even further, the AC regenerator prevents motor noise from getting back on to the AC that serves your other noise sensitive components. So even if speed is bang on without the motor controller, there are still benefits to be had.

Thanks!

There is an SDS listed here and on Audio Asylum.

Thanks Cerrot. Now the only problem is finding one. None of the retailers seem to have any.