"geoff" wrote in message
...
Peter Larsen wrote:
Steven Sullivan wrote:


The peak signal when recording vinyl comes frm the clicks, usually 6
dB higher than the signal for the large ones. Grammophone records and
quality playback of them can provide a very high quality sound IF and
only IF all links are good.

I have found it most useful to sample them at 96 kHz 16 bit so as to
save disks space, I don't see any logical reason in wasting it for
writting 16 binary ones for each sample, but I want a good sharp and
undistorted clicks in case automated click removal is relevant.
Mostly I just take the big ones out with fix single click

Record at 24 bits, then once you've got rid of your clicks, then you can
raise the overall level with less degradation.

Why 96/16 rather than 44k1/24 ? I don't follow that logic. The highest
freq recorded on most LPs was around 15KHz, apart from clicks of course...


I'm not sure I follow yours. Whilst the highest *recorded" frequency was
around 15kHz, the click spectrum would go much higher than that so
preserving the fast risetime of the clicks would be of value to automatic
click detection software. On the other hand the S/N ratio of no better than
70dB requires only a 13-bit ADC, leaving a margin of 3 bits (18dB) for click
headroom/ post digitising amplification even when using a 16-bit converter.
And it doesn't matter if high-amplitude clicks are clipped, as long as the
rise-time is preserved.

I would be astonished if anyone could tell the difference between an
original 24-bit digitisation and a 16-bit one when digitising vinyl.

In the old days of 405-line TV the (AM) sound channel would have a simple
impulse interference reduction limiter fitted. This worked on the fact that
the impulse would have a far faster rise-time than any audio content. For
this reason the band-width of the sound IF channel was kept far wider than
need for the audio, around 100kHz.


David.