First time I heard a TT isolation effect was in rural New Hampshire, five
miles at least from the nearest Interstate. The device was called
Vibraplane and it dealt with vertical and horizontal vibrations down to
2.5Hz. A switch on the air pump allowed it to be activated or disabled in
seconds and man! did it make an improvement. While "any decent isolation
feet should prevent them," true decent is going to cost because none of the
mere feet I've seen address the noisome lateral vibrations to any effective
degree.
The point is you don't need earthquakes to be in a seismic environment.
On Wed, Sep 19, 2012 at 4:57 PM, Tom Fine <[log in to unmask]>wrote:
> I think it depends on what kind of earth your turntable sits. I agree
> about a building in Manhattan over a subway line. I disagree about a home's
> concrete slab in a suburban area not known for seizmic (sp?) activity. The
> kind of resonances that naturally occur in the ground are sub-sonic and any
> decent isolation feet should prevent them. However, if you're having
> earthquake activity or even high wind activity that creates air-mass
> vibrations akin to a huge woofer, that probably can show us as rumble or
> skipping on most if not all turntables (maybe not those old Garrard console
> models that track at 5 grams and cut their own new grooves each time you
> play the record). Oh, HVAC systems will also cause rumble, especially on
> wood-framed floors.
>
> That said, floating the turntable platter (and the tonearm connection to
> the cabinet) and using a frictionless bearing (if such a thing existed)
> should, in theory decouple your spinng record and groove-reading cartridge
> from all external vibrations. Such a system doesn't exist, at any price,
> for any sized man.
>
> -- Tom Fine
>
> ----- Original Message ----- From: "Clark Johnsen" <[log in to unmask]
> >
> To: <[log in to unmask]>
> Sent: Wednesday, September 19, 2012 4:33 PM
> Subject: [Norton AntiSpam]Re: [ARSCLIST] High-end turntable
>
>
>
> Footfall susceptibility is the obvious vibration problem with many
>> turntables. Left mostly unsaid is the pernicious effect of low-level,
>> omnipresent vibration transmitted up from the earth. Most built-in
>> isolation methods and suspensions fail to stop this and those that
>> somewhat do, then fail to account for the far more worrisome lateral
>> shaking... the stuff that fells buildings in earthquake zones.
>>
>> It is my considered view that much of the difference heard among
>> turntables
>> (apart from the clearcut stuff like rumble) can be accounted for by their
>> susceptibility to this unsuspected vibration environment. One class of
>> exception: The very, very expensive 'tables that do seem to address this
>> situation, but I can't say for certain. One thing I do know, though, is
>> that clamping a 'table down tightly to the earth only allows more
>> ground vibrations to proceed into the unit.
>>
>> clark
>>
>> On Wed, Sep 19, 2012 at 3:37 PM, Tom Fine <[log in to unmask]>**
>> wrote:
>>
>> Hi Carl:
>>>
>>> You are right about the Philips with floor vibrations. Cheapo feet are
>>> the
>>> reason. I use an old IBM typewriter pad that used to sit under the
>>> Selectric typewriters so they wouldn't vibrate a desk. Plus it's on top
>>> of
>>> a heavy file cabinet sitting on a concrete slab, nowhere near any
>>> woofers.
>>> The touch-sensitive buttons were a koolio feature in the early 80's
>>> (along
>>> with big hair and "Flashdance"), but they get very insensitive over
>>> time. I
>>> now have to blow on my fingertips before operating them or they won't
>>> sense
>>> any touch. I'm not dead, but I do have dry hands and fingers. My mother
>>> (the original owner) had the same problem with those buttons. At her
>>> house,
>>> the turntable was in a cabinet that had cement under it and the speakers
>>> were in a different room, so no vibration feedback problems.
>>>
>>> In the case of both the Philips and the Technics servo systems, there's
>>> plenty of feedback to make speed accuracy and pitch accuracy if the
>>> system
>>> is functioning. One system that could get tripped up was Denon, which had
>>> two tape heads and a magnetic ring inside the platter as its system.
>>> That's
>>> only about one data point per second (2x 33 1/3 per minute), and some
>>> people can hear the system adjust speed on tracking-challenge stuff like
>>> fff to ppp on a good classical recording. I saw that tape-head and fixed
>>> magnet system used in one other place -- on AutoTec tape decks, that's
>>> how
>>> motion-sensing was done. Ampex used a light source, strobe wheel and
>>> light-detector on the AG-440C. I was taught old-school about tape
>>> spooling,
>>> and don't trust any motion sensing system. I always "rock and roll" to a
>>> dead stop, then hit stop. Diverging ...
>>>
>>> Anyway, as I've said numerous times, there is only so much "perfection"
>>> you're going to eek out of the _vast_ majority of LP records. Even a
>>> modest
>>> modern system (due to low-noise phono preamps and the general
>>> availability
>>> of decently compliant cartridges) will reveal how much rumble and hum and
>>> hiss is baked into the "golden era" records. Listen on headphones and it
>>> all hangs out. The early Westrex stereo cutters were tough beasts to
>>> wrangle, and the old lathes were rumbling to varying degrees of
>>> audibility.
>>> Plus the old tape machines had relatively high noise floors, old tapes
>>> hissed, etc. The problem with most "audiophile" records is that the
>>> content
>>> sucks and isn't worth hearing, performance-wise and/or recording-wise.
>>> Some
>>> reissue LPs of more recent vintage are wonderful exceptions to that
>>> admittedly blanket statement.
>>>
>>> -- Tom Fine
>>>
>>> ----- Original Message ----- From: "Carl" <[log in to unmask]>
>>> To: "Tom Fine" <[log in to unmask]>
>>> Sent: Wednesday, September 19, 2012 3:11 PM
>>> Subject: Re: [ARSCLIST] High-end turntable
>>>
>>>
>>> Pardon the imprecise language, professor. I mean to say the best
>>> playback
>>>
>>>> of LP I have yet heard. :)
>>>>
>>>> You mean the Philips model that used touch-sensitive buttons? I had one
>>>> of those around 1978. It was good, but the suspension was very
>>>> sensitive to
>>>> footfalls. Speed is not the only thing that's important, but it should
>>>> be
>>>> right. The original Rega Planar 3s ran fast! (Purposely?) On how many
>>>> TTs
>>>> can you hear the pitch go up after a loud passage? You're right about
>>>> the
>>>> Slovak stuff - they're toys. I'd rather have what I think you've got -
>>>> Technics? But then it would be fun to put yours next to a mid-range
>>>> Rega,
>>>> and compare them for overall tunage. The Technics would probably win for
>>>> value, but of course, that's a very personal evaluation.
>>>>
>>>> Small things mean a lot with this black magic stuff, and they cost. The
>>>> tonearm is important and so is the way it interacts with the rest of the
>>>> structure. The fewer you sell, the more expensive each is, forming a
>>>> commercial feedback loop. I know from working in high-end retail, that
>>>> nobody actually pays $170,000 or $35,000 for one of these things, unless
>>>> the buyer's favorite charity is his audio dealer. On the Clearaudio, the
>>>> customer could demand a 25% discount and the dealer would still make
>>>> $15,000. No dealer would say no, right?
>>>>
>>>> Now, the question of value, .... that machine looks absurd. Clearaudio's
>>>> normal stuff pales in comparison to SME's workmanship, but their stuff
>>>> generally is better than VPI or others at below 8k (my buddy is a dealer
>>>> for those makes and others). The SME's price makes some sense given the
>>>> scope of the market, inherent quality, and the performance you get.
>>>> Seriously. I have owned (of the good ones) Thorens, Luxman, Oracle,
>>>> Micro
>>>> Seiki, VPI, Nottingham, and now for some years the modest little SME 10.
>>>> They're all good, all different, and there is a hierarchy of
>>>> reproduction
>>>> quality that, to me, is worthwhile.
>>>>
>>>> In high-end audio, high cost also is its own priority. It is sometimes
>>>> money for nothing and when it is shysterism, that's wrong. I'm okay with
>>>> your populist sentiment, Tom. I've spent most of life on a shoestring
>>>> and
>>>> right now Micky and I are literally below poverty income - only
>>>> partially
>>>> by choice. So far, it has made sense to me to have a better TT than a
>>>> car.
>>>> Hope that doesn't change!
>>>>
>>>> -----Original Message-----
>>>>
>>>> From: Tom Fine <[log in to unmask]>
>>>>> Sent: Sep 19, 2012 1:17 PM
>>>>> To: Carl <[log in to unmask]>
>>>>> Subject: Re: [ARSCLIST] High-end turntable
>>>>>
>>>>>
>>>>> Aside from obvious things like unacceptably high rumble, speed
>>>>> inaccuracy and tonearm resonances,
>>>>> which should only occur on cheapo junk among modern-production
>>>>> turntables, what exactly is the
>>>>> "sound" of a turntable? Shouldn't the "sound" of a turntable be the
>>>>> sound of the cartridge with good
>>>>> design rendering rumble and mechanical resonances inaudible and perfect
>>>>> speed accuracy eliminating
>>>>> wow and flutter?
>>>>>
>>>>> By the way, use any objective test record (Analogue Productions, Shure,
>>>>> the old Command test record,
>>>>> CBS Labs, etc) and a frequency counter and see how inaccurate the speed
>>>>> is on the lower-end
>>>>> "audiophile" belt-drive turntables. I discovered this problem on a
>>>>> MusicHall turntable and then
>>>>> measured the same problems on all of those similar turntables made in
>>>>> Eastern Europe. I think the
>>>>> problem is a combination of a cheapo motor and a cheapo bearing, which
>>>>> makes speed accuracy
>>>>> impossible without a platter too heavy for the cheapo motor to move.
>>>>> The
>>>>> old Thoren belt-drives had
>>>>> it right -- if you're going to go that route (and I prefer direct-drive
>>>>> in the first place), then
>>>>> you better have a massive platter and a precision bearing. Philips had
>>>>> a
>>>>> clever system that they got
>>>>> down to very low price points by using a non-exotic platter with a good
>>>>> but non-exotic bearing and a
>>>>> DC servo motor driving the belt, so the motor would make up for
>>>>> whatever
>>>>> the consequences with a
>>>>> light platter. I've got one of those Philips turntables and it measures
>>>>> speed-accurate like a
>>>>> Technics 1200 direct-drive. Both have very low flutter characteristics
>>>>> too.
>>>>>
>>>>> As for tonearm resonances, that's another problem with the low-end
>>>>> "audiophile" tables coming out of
>>>>> Europe. Those hollow-metal tonearms very audibly resonate with many
>>>>> cartridges, especially on
>>>>> deeply-cut records and on warped records. Plus the premative
>>>>> string-and-weight anti-skate
>>>>> "mechanism" is a joke. For the same money, the Chinese
>>>>> Technics-knockoffs will give you better speed
>>>>> accuracy, a better-designed (but not necessarily better-executed)
>>>>> anti-skate mechanism and, if you
>>>>> get a real-deal Technics heavy rubber platter mat instead of a felt
>>>>> "skate mat" typically included,
>>>>> you get equal or lower rumble.
>>>>>
>>>>> -- Tom Fine
>>>>>
>>>>> ----- Original Message ----- From: "Carl" <[log in to unmask]>
>>>>> To: <[log in to unmask]>
>>>>> Sent: Wednesday, September 19, 2012 12:48 PM
>>>>> Subject: Re: [ARSCLIST] High-end turntable
>>>>>
>>>>>
>>>>> It's a statement all right, and so is the price. Makes the best record
>>>>>
>>>>>> player I've ever heard seem
>>>>>> cheap. The SME 30 is about $35k. Yes, if I had that kind of money, I'd
>>>>>> own one. Better than
>>>>>> wasting that much cash on an automobile.
>>>>>>
>>>>>>
>>>>>> -----Original Message-----
>>>>>>
>>>>>> From: Randy Lane <[log in to unmask]>
>>>>>>> Sent: Sep 19, 2012 11:42 AM
>>>>>>> To: [log in to unmask]
>>>>>>> Subject: [ARSCLIST] High-end turntable
>>>>>>>
>>>>>>> Anyone own, plan to buy, or used one of these yet?
>>>>>>>
>>>>>>> *http://tinyurl.com/5w2zw7*
>>>>>>>
>>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>
>>
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