Vinyl temperature

[circui...@gmail.com]

The elasticity of vinyl (and many other materials) varies with temperature.
It seems to me that at lower temps would allow the phonograph stylus to more faithfully follow groove displacement.
Would there be any advantage to a turntable which chilled the record during playback?
And what would be the optimum temp? Too low and the vinyl would enter the glass transition and become brittle.
i thought of this reading a discussion about using summer car tires in cold weather.

[Peter Wieck]

It is an interesting question, but you first need to do some math, and then to understand the forces involved.

First (and I will first calculate in old and new currency here):

How fast is the stylus going?

A 12" Disc uses from about 11-7/8" to about 5" for actual signal. To make life easier, we will use 12 and 4. Meaning that the average diameter is about 8". Pi x 8 x 33.33 = distance per minute. Use 838 inches per minute. Use 70 feet per minute. Which is about 1.16 fps, or 4,200 feet per hour. On average.

How much does the stylus "weigh"?

Use 2 grams. Use 0.2 x 0.7mm as the stylus bearing area. Giving a total bearing surface of a bit more than 0.14 sq.mm. That comes to 51 grams per sq.mm. One sq.mm. = 0.00155 sq.in. Or, 645 sq.mm. = 1 sq.in. 51 x 645 = 39,345 grams per square inch (39.345 kilos). = 1,405 ounces per square inch, or ~87 pounds per square inch. Drag something that has a bearing surface of one square inch and weighs 87 points at 70 feet per minute over a rough vinyl surface while bouncing it 10,000 times per second and, I suspect, there will be some evidence of that passage. (70 fpm = 21.3 mpm)

Now, consider that said sylus is jumping up, down and side-to-side at anywhere from about 20 to about 20,000 times per second and all parts between. That it is as hard as (at least) an industrial sapphire or diamond is a good start. Steel needles back in the day moved much faster, but had a much greater bearing area - but were designed to play one (1) time per use. ONE TIME. Edison learned early, and developed the vertical diamond stylus.

Cutting to the chase:

Too cold, and the diamond (read small, dull chisel) will shear off the sharpest points on the groove. Too hot, and the vinyl will be in a plastic stage and those points will be rounded, or even folded over. Vinyl has no memory, so would not 'recover' as some plastics.

Ideally, any given vinyl disc should be played no more than once (1 time) per 24 hours to give the surface a chance to equalize in temperature and to give the peaks and valleys a chance to re-polymerize with the rest of the substrate. I would go so far as to suggest that no vinyl disc should be played about about 80F or below about 85F (15.5C to 29.5C).

As to "summer" tires vs. "Winter" tires: once the vehicle has gone a few miles/km on smooth pavement, the friction has warmed the system to the point that it should make no functional difference. This is not to suggest that there are no differences in rubber formulations - there are, and they are significant. And, those differences are most significant when the tires are actually being used per their design: A winter tire on an icy or ice-and-snow mix will have definite advantages over a summer tire, even were it to have an aggressive tread design. And a winter tire driven on a hot asphalt road in the middle of the summer will wear out very quickly. But on dry pavement in the winter after those first few miles, the tires are about equal - based on actual tread design.

Peter Wieck
Melrose Park, PA

[circui...@gmail.com]

To talk about stylus pressure against the vinyl groove one must also consider effective mass of the stylus + cantilever etc. combined with acceleration of that moving mass, F = MA.

Re. tires, the manufacturers of high performance summer tires typically warn not to use them below ~40F. The problem is not traction related, the rubber compound becomes brittle and prone to cracking. Also, one cannot count on friction warming the treads if the vehicle is driven at low speeds. This link talks about using and storing HPSTs:

http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=220

[Peter Wieck]

On Sunday, October 30, 2016 at 9:03:03 AM UTC-4, circui...@gmail.com wrote:

Please note the interpolations:

> To talk about stylus pressure against the vinyl groove one must also consider effective mass of the stylus + cantilever etc. combined with acceleration of that moving mass, F = MA.

True, but keep in mind that for the stylus to do its job - which is to transmit the vibration from the groove to the magnet (or coil) to the fixed coil in the cartridge, it must be fairly rigid (at least horizontally). As I understand it, there is considerable low-frequency vertical damping to account for warped records, but horizontal damping is minimal.

> Re. tires, the manufacturers of high performance summer tires typically warn not to use them below ~40F. The problem is not traction related, the rubber compound becomes brittle and prone to cracking. Also, one cannot count on friction warming the treads if the vehicle is driven at low speeds. This link talks about using and storing HPSTs:
>
> http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=220

All true. But, HP tires are a different class from the common herd. However and furthermore, tires age out in 3-5 (with some few lasting as long as 10 in low ozone areas) years - another very seldom understood issue, especially with Great Aunt Esmeralda, who drives only to church, Bingo, and the market - her tires will be 'done' long before they are 'done'.

[Robert Peirce]

On 10/31/16 1:10 PM, Peter Wieck wrote:
>> Re. tires, the manufacturers of high performance summer tires typically warn
not to use them below ~40F. The problem is not traction related, the
rubber compound
becomes brittle and prone to cracking. Also, one cannot count on
friction warming
the treads if the vehicle is driven at low speeds. This link talks about
using and
storing HPSTs:
>>
>> http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=220
>
> All true. But, HP tires are a different class from the common herd. However
and furthermore, tires age out in 3-5 (with some few lasting as long as
10 in
low ozone areas) years - another very seldom understood issue,
especially with
Great Aunt Esmeralda, who drives only to church, Bingo, and the market - her
tires will be 'done' long before they are 'done'.
>
> Peter Wieck
> Melrose Park, PA
>

I find tracking your car solves this problem nicely. I can't think of
any other reason to use high performance tires. I run all seasons on my
daily driver.


[ Please bring the conversation back to audio topics. -- dsr ]

[Peter Wieck]

Oh, I dunno. Sometimes sidebars have a place in any conversation - and given the scarcity of posts to this group these days, perhaps any conversation might be welcome as a 'proof of life'.

As to audio stuff, two weekends ago, I paid $40 for the following at a yard-sale: Dynaco FM3, ST70, ST80, ST120. The seller stated that they were his 'rejects'. I asked if he might have any other such items - he replied that I should have been there earlier.... Ah, well.

And, to be even more risque - I will request for those Americans who are able within this group that they follow the advice of one Alphonse Gabriel Capone: Vote early and vote often!

[angusstewa...@gmail.com]

Doesn't all of this rather make the point that - in terms of fidelity to the master - vinyl is *inherently* inferior to modern high-res digital?

[isw]

In article <earsog...@mid.individual.net>,

angusstewa...@gmail.com wrote:

> Doesn't all of this rather make the point that - in terms of fidelity to the
> master - vinyl is *inherently* inferior to modern high-res digital?

It's even "inherently" inferior to ordinary digital recordings. And, the
more you play the record, the more inferior it becomes.

Isaac

[Peter Wieck]

I think the question is directed at other-than-CD sources - MP3 and such, and the definition of "high-res".

I have written this in the past - music has been dumbed-down greatly in the last 30 years or so. I remember back in the 60s, a decent speaker at the bottom of the line would have an 8" woofer and either a very small (1.5") conventional or dome tweeter. As the line improved, the woofers got larger, the tweeters smaller, and mid-ranges joined the choir. And then the drivers multiplied. Meanwhile, amplifiers got bigger, heavier and more powerful, usually in large increments. THEN, something strange happened. Everything started going backwards such that one may pay tens of thousands of whatever currency is handy for fly-weight amplifiers in single-digit watts driving tiny little speakers configured wildly in massive baffles and so forth. And, we call it "HiFi".

Good sound is about shaking air. Shaking air takes energy. When we stop shaking air, we stop having good sound. And, unless we use headphones, or are listening in a closet, we need to shake a significant amount of air to have good sound. Kinda-Sorta circular reasoning. Oh, and one more thing: the concept of the "Sweet Spot" was formed - if only to legitimize the lack of ability to shake air sufficiently outside of that sweet spot for any sort of sound-stage larger than a 10" cube.

However, if we fall away from the concept, and listen with tiny little speakers with tiny little drivers, or worst of all - earbuds - then, yes, Virginia, about any digital source is going to be superior to vinyl as it does not degrade over time. BUT, also, both are superior to the reproducing engine.

[Scott]

On Wednesday, December 7, 2016 at 5:53:22 PM UTC-8, angusstewa...@gmail.com wrote:
> Doesn't all of this rather make the point that - in terms of fidelity to the master - vinyl is *inherently* inferior to modern high-res digital?

*This* doesn't really make that point. That point has been long made. And it's great that many significant works that were originally recorded on analog tape can now be archived witha level of accuracy that they are for all practical purposes perfect copies of the feed coming off of the analog tape playback. Ofc ourse this does not address the issue of the analog tape playback. That is very dependent on the tape deck, the set up of that deck and the speed at which the tape is played back.

For purposes of archiving I am all in on hi res digital. For purposes of SQ for my personal playback I still prefer vinyl in most cases.