I'm trying to understand what it is in terms of, say, framerates in video. Supposedly, visually they say we consider motion to be "smooth" at 30fps, but I know from playing computer games that anything under 60fps tends to look choppy and 100fps looks much smoother.

If we think of the CD as storing 44.1K "sonic" frames per second, how many "sonic" frames per second is stored on an LP?

-Mike...

P.S. This is not a troll. I've seen enough Vinyl vs. CD debates in my time. I'm just hoping that the beanie-headed inmates could help me with a technical question.

 Re: Technical question about vinyl - macaque 10:27:31 12/11/02 (3)
 Re: Technical question about vinyl - Leisure7 11:58:23 12/11/02 (2)
 Re: Technical question about vinyl - macaque 06:41:04 12/12/02 (1)

...

Show full thread outline!

 Re: Technical question about vinyl - macaque 10:27:31 12/11/02 (3)
 Re: Technical question about vinyl - Leisure7 11:58:23 12/11/02 (2)
 Re: Technical question about vinyl - macaque 06:41:04 12/12/02 (1)
 Re: Technical question about vinyl - Leisure7 14:06:57 12/12/02 (0)
 Re: Technical question about vinyl - Penguin 18:42:26 11/19/02 (0)
 rough calculation... - chillysalsa 18:01:03 11/18/02 (17)
 Re: rough calculation... - John Escallier 14:30:56 11/19/02 (12)
 stamping process - chillysalsa 09:40:56 11/20/02 (11)
 Re: stamping process - John Escallier 10:04:08 11/20/02 (10)
 You CAN open 2 explorers. Why not? - orejones 11:37:26 11/21/02 (2)
 You can also... - bhjazz 13:02:19 12/07/02 (0)
 Son of a gun, it worked. - John Escallier 11:45:38 11/21/02 (0)
 Download the latest version of Netscape :-) - Penguin 10:40:14 11/20/02 (5)
 Netscape is okay, but... - bhjazz 13:04:20 12/07/02 (0)
 That's just vat dey'd expect me to do. - John Escallier 10:58:22 11/20/02 (3)
 Get one of these for home - Penguin 12:14:25 11/20/02 (2)
 Gonna order it before end of day - John Escallier 12:45:46 11/20/02 (1)
 They are very secure (nt) - Penguin 19:54:47 11/20/02 (0)
 Google, of course - John Escallier 10:10:44 11/20/02 (0)
 That's the sort of calculation I would have thought about… - David Aiken 00:17:57 11/19/02 (2)
 But now that I've thought further… - David Aiken 12:09:40 11/19/02 (1)
 It seems comparison is like round peg in square hole - chillysalsa 13:13:39 11/19/02 (0)
 Thanks (nt) - mike_decock 19:44:51 11/18/02 (0)
 Re: Technical question about vinyl - jeff mai 16:32:55 11/18/02 (2)
 That's kind of along the lines I was thinking... - mike_decock 19:41:58 11/18/02 (0)
 Re: Technical question about vinyl - John Escallier 17:01:03 11/18/02 (0)
 1 per song. - davewe 16:19:38 11/18/02 (0)
 Re: Technical question about vinyl - tcain 15:38:54 11/18/02 (3)
 Re: Technical question about vinyl - middleground 18:04:25 11/18/02 (2)
 Re: Technical question about vinyl - tcain 18:37:11 11/18/02 (1)
 Re: Technical question about vinyl - john curl 15:22:17 11/21/02 (0)

Better to consider the quality of the vinyl.

Or the freq response of the cutting head and associated electronics.

TTFN, John

If they use electrodeposition to produce the stampers for the 'pits' on the die, then typically the dimensional accuracy for the smallest feature that can be produced is ~0.5 microns (0.5 x 10^-6 m)

Vinyl travels at speeds across the stylus at roughly: 1.6 cm/s to 0.8cm/s (at start & end) - or 0.016 - 0.008 m/s

Thus, the sample rate is approx:
0.016 / 0.5 x 10^-6 per second = 32 kHz at start
and 16 kHz at the end.
(that's for EACH channel of stereo)

Happy listening...

==Absolutely.

>>laying the argument of the superiority of analogue reproduciton as being based on some uninterrupted continous wave the way God intended music to be, a little bare?

==No more than it ever was 50 years ago when Lp was king.

I maintain that no medium is best, each has problems and always will. I may see holographic 3D optical storage mediums for cheap in my lifetime but will they let you hear "the hairdoo's"? I doubt faster sample rates will change the sound much. I think digital is quite good today. I find analogue far more problematic and disapointing when playback noise takes away from the music. Still, the sheer beauty of the performance can be all powerfull. I have a treasured Calvin Jackson and his All Stars lp from '57, scratched, furrowed and mono still delivers far more energy, tonal character, and ambiance than most any digital I've heard. All those scratches won't impress anyone but a music lover, and that's why I still play it. I listen for materials sounds ie: drumsticks, maple wood tips or nylon, Ludwig or Pearl. You can do that with LP in spite of spurious stylus movements. On the other hand the tonal character changes record to record. Stylus cleanlines is a vocation. Got a pet in the house? TC

The other aspect of this that I'm thinking about is that, as an analog medium, the size (time window) of these discrete steps would not be a constant. It would be somewhat of a randomized sample rate.

My theory is that randomized distortions are less irritating than organized distortions. Kind of like the screendoor/stairstepping of a digital picture looking less "natural" than a picture taken on film with equivalent "resolution", but using random-sized dots.

-Mike...

Building on your comments, the stylus is really only producing musical information when it's direction of travel or speed changes because of irregularities in the groove wall. A totally smooth, unmodulated groove like the lead in and lead out grooves produces no sound at all, or as close to that as possible.

The question then becomes how many changes in travel can you pack into a second of music which is what your calculations address. As you point out it's higher at the start of a side than the end, so the 'sample rate' is always changing.

So, some further questions:

1 - Given that not all music requires as many modulations to the groove wall as can be packed into the space at maximum density, does that imply that the sample rate is lower when the groove wall isn't heavily modulated? and

2 - Given stylus tracking constraints, is there a limit to the density of modulation that can be tracked which is lower than the figure in your calculation and does that imply a lower sample rate as well?

David Aiken

I now wonder about this whole approach, however. In digital, the sample rate determines the upper frequency limit which is half of the sample rate since you need at least 2 points to define the wave form. On this calculation for a n equivalent sample rate for vinyl, the sample rate on the inner groove is about half that of the sample rate on the outer groove. While there may be some variation in the upper frequency limit of vinyl between the inner and outer grooves, the upper frequencies on the inner groove don't seem to be compromised by anywhere near that degree in relation to the outer groove and these sample rates, if they were digital, would yield upper frequency limits of 16 kHz for the outer track and 8 kHz for the inner track. Vinyl definitely exceeds both of those frequency limits so I don't think this approach will work at all.

David Aiken

While you need 2 digital points to fit wave, the analog format of vinyl means that even on a single 'bump', you still actualy have an infinite number of points to constructing that curve. You could technically say that vinyl has infinite sample rate, but I'm just calculating it on the limit to 'bump' size: ie, the frequency that can be extracted from that feature.

Of course, everything is still dependant on the factors of how fast the stylus can be moved, the electrical connections, etc etc.

I'm confused. I understand pits for cd stamping. Is that the term used for vinyl?

Cheers, John

dee
;-D

Certainly sounds like it..

But isn't the vinyl started by cutting a master, where the wall features (highest frequency limit) are determined by the radius of curvature of the side of the cutting needle? Whereas the CD is photolithography? Or am I (carbon) dating myself?

Course, now that I've posted this, I'll have to google it. Shoulda googled first, but can't open 2 explorers.

Cheers, John

dee
;-D

Can't do so at work, the IT people try to standardize, but home is a definite possibility.

Is it less vulnerable to hacking? I've '98 se on my home computer with norton antivirus, on a cable modem. Constant hack attack as IP never changes.

TTFN, John

• http://www.cdw.com/shop/products/default.asp?ProductID=56163

Had a hub, but was afraid to connect to the modem. Routers apparently provide a hard firewall.

I'll be able to connect all 4 of my systems at the same time. It's been a pain, burning 8cm CD's to transfer info. Had a zip, but hated it.

Thank You

John

At least, it works fine for me: sometimes I go check some data, while writing something like this at AA...

Regards

BF

Cheers, John

Click File, New, Window

or

Hold down your Ctrl key and tap your N key. Voila! New Window!

You might also use the Open command from the same menu, along with the previous commands. Whn I see someone add in a website name on the forum but it isn't listed as a hyperlink (in blue), I do the following:

Take the mouse and highlight the link
put your pinkie on the left Ctrl key
tap the C key (copy)
tap the N key (opens new window)
tap the V key (pastes the copied web address)
hit enter.

After a little practice, it goes very fast. I think I can open pages faster than popups with thie method! hahaha.

Enjoy!

bhjazz

For a low profile browser that doesn't support alot of internet stuff, you might also try Opera. Very, very fast, low overhead.

bhjazz

That being said one often overlooked part of digital audio is that as implemented it cannot exactly recreate the original analog signal. The theory allows taking samples at discrete time intervals of a band limited signal and recreating the original analog signal exactly (sampling thereom) assuming you can make a perfect low pass filter. For all this to work the samples have to be continuous and not discrete. 16 bit quantization of the samples is the main thing preventing the realisation of a better rendition of the original signal (you would like an inifinite number of bits). I think high-res audio has the potential to sound a lot more like analog because of the bit resolution more so than the sample rate. You get 256 times closer to "continuous" samples with 24 vs 16 bits. Higher sample rates allow you build low pass filters that are not necessarily ideal but very close to ideal in the audible band. This has been exploited for a long time with oversampling.

There is no sample frequency or amplitude quantiziation in analog, except that at some point the molucules which control the movement of the stylus are discrete, in terms of digital audio you could think of the amplitude of the signal being represented by a number of bits approaching inifinity and infinitely small time sampling (allowing unlimited bandwidth).

It would be interesting to have a format which was discrete time sampled but used a stylus instead of a DAC to have a continuous "sample" level based on molecular bits. In essence, high rez digital formats are trying to emulate that type of situation in a more convenient (and less error prone) format.

That being said, I just got a Music Hall MMF-7 turntable and there is something so magnetic about the sound of vinyl I have a hard time listening to CDs now.

If you don't like the sound of your CD player, then get a new CD player and enjoy all the music encoded on your discs as well as the treasures in your vinyl library.

One of the major differences though is that digital systems introduce noise that is correlated to the actual signal (due to quantization of the sample amplitudes) and correlated noise in the clocking also creates a non-random type noise. This may explain the qualitative differences people hear bewteen analog and digital. Granted most turntable produce an inner groove distortion which can be quite annoying as well. And wow/flutter of the platter can also contribute to correlated noise, especially with servo controlled motors.

I am not giving up on CDs... I have too much invested in them. I find that even big clicks or pops in vinyl don't ruin the illusion of the music - I assume because they are completely uncorrlated to the music your brain treats them as separate sounds. "Hey, someone is popping popcorn on my speakers" but it doesn't ruin the illusion of an orchestra playing in my room. Crappy CD players do ruin the illulsion of the orchestra playing in my room - even with 110dB S/N ratio. Why is that?

In my experience, those who claim to hate all digital simply do not like the sound of the particular CD playback equipment they own. Even if it is very expensive, based on what I've heard when visiting them, I have to agree with them. There are better and worse CD players just like in everything else. I have and enjoy the Wadia 861. It has a very strong analog output stage, which IMHO contributes to its good performance. Crappy CD players have crappy output stages and power supplies contaminated with correlated and noncorrelated digital grunge. Did you ever experiment with the Radio Shack CD3400? That device demonstrated clearly how a well-regulated supply could clean up the sound.

The WOW distortion from playback of LPs with off-center holes makes it impossible for me to believe there is a real performance going on in the room, regardless of how well the pickup and phono stage reproduce the sound. This distortion is very annoying to me, and I hear it on most LPs. I'm sure I had been trained to ignore it back in the days before CDs, just as I'm sure I'm well trained now to ignore whatever correlated noise the Redbook CD playback method produces, even with good equipment.