Turntable drive belt ..

[The Natural Philosopher]

Quantum reality.

This dicates the ultimate noise floor of any sound system for example.

Yes, you can actually hear the individual atoms and molecules banging on the microphone diaphragm. And your eardrum apparently.

The noise floor in electronics is actually related to the number of electrons in the seimiconductor device that comprise the signal. You can't get better than +- 1 electron resolution no matter what you do, with electronics.

If you boost your signal and digitise it accurately enough, that +- 1 electron might be +- 4 bits or so, at which point your quantization noise is well below the digital noise of the (so called) analogue signal anyway.

Just because w like to model the world in smooth continous lineaer functions, doesn't mean that is how the world actually is. It's just a reasonable approximation at the macro level we live at.

At the quantum level is all either yes or no type stuff. The integral of all the quantum states approximates to the smooth functions we think are the natural laws.

[bigcat]

example.

can you tell us any real world implementation that does this though. Anyone can dream.

Indeed, but none of that makes real life digital.

NT

[The Natural Philosopher]

?eh? its prefectly possible for any recording studio to push a mic channel to the point where the noise exceeds the quantization level of the A to D. In fact most would do so routinely.

Er...are you as thick as you appear to be?

[OldBill]

Waste of time trying to get the TT working. Those tracks can all be downloaded for nowt

[bigcat]

integral> > of

I think your definitions of digital vs analogue are off. The fact that all analogue signals are a given whole number quantity of electroncs does not make them digital, despite the obvious similarity.

You keep making assumptions that I dont really think are accurate.

NT

[Dave Plowman (News)]

I've got a Thorens belt driven deck and it's anything but a rubber band. It's a carefully made rubber band with a controlled width and thickness. And a rough surface for maximum friction.

FFS, what's a fiver for something that works properly and has a life of about 10 years + ?

[Dave Plowman (News)]

Most analogue signals went through a magnetic tape stage at some point, and the size of the individual magnets on that tape - ie the coating - were surprisingly analogous to digital recording. As are the size of the individual polymers? on a vinyl disc.

Some think that analogue gives an infinite variety of levels and 'sampling' but this just ain't true when listening to a recording.

Good analogue can easily give a sig noise of about 100dB if it's not recorded on analogue. Digital can be what you require it to be - but limited by the analogue at both source and destination.

[T i m]

But that's not a cheap / basic turntable is it Dave? I've got a Rover but it's anything but a Porche? ;-)

I'm sure it is.

Ok, howabout you buy it for me and then you can have the deck for the

9.99+ years after we have finished experimenting with it? ;-)

*If* I have need to order something from Maplin and can tack a belt onto the order or if I actually go past a HiFi shop that has one for less than a fiver I might just buy one. In the mean time the deck is back in the loft where it has spent the last 10+ years ... ;-(

All the best ..

T i m

p.s. I could easily find 10 things to spend 'just' 5 quid on ..

[T i m]

Well indeed .. other than it was partly an excercise for my daughter re 'records' ;-)

"Oh, you can use both sides ... how do you select the next track .. how do you do random or shuffle .. where does it plug into my PC ... " ?

All the best ..

T i m

[Owain]

If they're worthless records can they be played with a drawing pin through the back of a paper cup?

And for my next trick, how to work a twirly dial telephone...

Owain

[T i m]

Well I'm not sure she thinks they are worthless .. but then she hasn't heard these particular tracks before (they are older offerings). Maybe I can find one of the other arf's Cliff albums to 'play with' ..

Funny, I was explaining that one to the missus tonight .. why our replacement MF PBX was 'better' than the LD one ..

Cheers ..

T i m

[bigcat]

NT

[The Natural Philosopher]

? what is digital if not a systemn of encoding using a whole number of finite sized elements?

Analogue is simply digital encoding using a finite sized electron as the smallest 'bit'.

I think you will find that is your problem, not mine.

The world apprears to be - as far as quantum physicists are concerned - made up of a huge number of binary transitions between quantum states.

The great mystery - and believe me it is a mystery - is why these average out so that we can crudely represent them by linear equations.

Nevertheless, as we go deeper, the quantum nature is revealed - in the hiss and noise of our electronics. That is more or less us hearing individual quantum jumps.

If you boost the level and then convert to a higher resoulution digital signal than the hiss suggets, your quantization noise is totally buried in the 'analogue' noise so in theory, you can can approach the quantum limits as closely as you like.

In the limit, there is no such thing as 'analogue' in the sense that most people mean, and 'digital' is every bit as good on noise and jitter, and in every other way better.

Now of copurse if you choose to try and comp[ress our data into an inadeqyuate number of bits, then that is an entirely different story.

Nevertheless, CD sampling rates are good enough to exceed vinyl type performamnce in almost every single respect, quie easily.

[Dave Plowman (News)]

It's the second harmonic distortion inherent in vinyl that most appear to like.

If you copy an LP to CD carefully and set up a proper double blind test between that LP and that copy, none will tell the difference.

Do it the other way - copy a CD to LP, (and I have ;-)) - everyone will notice a difference.

FWIW, it's not the same thing buying the same piece which has been released on both vinyl and CD - they may (probably) have gone through different mastering - ie are not just straight transfers from the same master.

In other words, vinyl is not and never was a clone of the master. It adds its own footprint. Some types of music *may* be enhanced by this to some ears. But an accurate recording medium it's not.

[The Natural Philosopher]

Third harmonic I would buy. second would be assymetric, and I suspect unlikely

I agree.

[Joe]

Any medium which saturates (how many don't?) will generate odd harmonics. Records are also prone to some strange distortions, such as the one produced by a radial arm tracking a groove created by a parallel-tracking master cutter, and the one produced by tracking a groove cut with a cutting head, using a stylus. The more hyper- elliptical, the better, but you can never get it right.