Sound card for recording
 

"Tony Houghton" wrote in message
...
I'd like to make some recordings, maybe transferring some gems from my
vinyl collection to digital etc. I'm wondering whether I should use a
better sound card than the onboard sound.

I know one of the regulars here occasionally posts about an almost
universal design flaw on sound cards where the input circuitry clips
well below the potential ability of the A/D convertor or something. I
did try recording from vinyl via a T/T preamp to a basic onboard sound
card a few years ago. The preamp has no gain control and ISTR the result
did sound slightly distorted as if clipped.

I've got one of those old Santa Cruz/Sonic Fury cards lying around,
which were reckoned to be pretty good in their time. Would it be worth
installing that for recording? I found an old review:

Audio Converters: Dual AC-97 2.1 audio codecs with hardware full-duplex
for simultaneous record and playback and up to 48 kHz sample rates.
18-bit A/D converters for high-resolution recording. 20-bit D/A
converters for high-resolution playback of up to 6 independent streams.

Alternatively I could probably borrow my friend's EMI external USB sound
adapter which he bought especially for semi-professional recording a few
years back. Significantly better still?

--
TH * http://www.realh.co.uk


Try uk.rec.audio

--
Michael Chare

Sound card for recording
 

In article , Michael
Chare
wrote:
"Tony Houghton" wrote in message
...
I'd like to make some recordings, maybe transferring some gems from my
vinyl collection to digital etc. I'm wondering whether I should use a
better sound card than the onboard sound.

Try uk.rec.audio

Tony can perhaps guess what my response will be from reading already what
I've written elsewhere. However my basic preference is to use an audio
recorder that is not connected to a computer during recording.

This avoids any problems caused by the computer not being able to collect
samples correctly, interference, hum loops, etc, etc.

I've tended to use CD Audio recorders like the Pioneer PDR-509. But am
currently looking at buying a Tascam HD P2. Something like the 509 is quite
cheap, but limited to CDDA (16bit / 44.1ksamples/sec). Whereas the Tascam
goes up to 192ksample sec and 24 bit. But is more expensive. :-) But
there are a number of other audio recorders around.

This means I use the recorder just as you might have used an older cassette
or reel-to-reel as part of the hifi system with no computer attached. Then
carry the recordings on CD to the computer for editing and final writing to
CDDA, or use from a server as you prefer.

For the modern 'solid state' recorders, you'd obvious use either a USB
(or firewire) link or carry the memory card instead of a CD for the
transfer. Treat that as a separate operation to the actual recording
process.

I'm personally wary of using a 'soundcard' as it means a risk of the
computer disturbing making best-quality recordings for various reasons.
However despite this I'd agree that with the better soundcards and a
carefully setup system that approach works well. But I would not use any of
the internal 'soundcards' on any of the computers I have for recording
analogue sources as the results would be poorer than a stand-alone CD Audio
recorder.

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

Sound card for recording
 

"Michael Chare" wrote in
message
"Tony Houghton" wrote in message
...
I'd like to make some recordings, maybe transferring
some gems from my vinyl collection to digital etc. I'm
wondering whether I should use a better sound card than
the onboard sound.

I know one of the regulars here occasionally posts about
an almost universal design flaw on sound cards where the
input circuitry clips well below the potential ability
of the A/D converter or something. I did try recording
from vinyl via a T/T preamp to a basic onboard sound
card a few years ago. The preamp has no gain control and
ISTR the result did sound slightly distorted as if
clipped.

That's a stupid problem that was created by badly engineered products. It is
a situation that is easy enough to address with a simple attenuator.

I've got one of those old Santa Cruz/Sonic Fury cards
lying around, which were reckoned to be pretty good in
their time. Would it be worth installing that for
recording? I found an old review:

If it still works and if you can find appropriate drivers for it, yes.

Audio Converters: Dual AC-97 2.1 audio codecs with
hardware full-duplex for simultaneous record and
playback and up to 48 kHz sample rates. 18-bit A/D
converters for high-resolution recording. 20-bit D/A
converters for high-resolution playback of up to 6
independent streams.

Alternatively I could probably borrow my friend's EMI
external USB sound adapter which he bought especially
for semi-professional recording a few years back.
Significantly better still?

Whatever works.

Because of the LP format's inherent technical failings, digitizing LPs is
not all that challenging of a task for even an one of those on-board audio
interfaces that comes with most motherboards.

Sound card for recording
 

In article , Arny
Krueger
wrote:


Because of the LP format's inherent technical failings, digitizing LPs
is not all that challenging of a task for even an one of those on-board
audio interfaces that comes with most motherboards.

In principle it is slightly complicated because of the possibility of
unpredictably high peaks. But in practice this doesn't seem a problem in my
experience and 16bit samples should be fine if you allow for enough
headroom when setting the gain.

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

Sound card for recording
 

On Thu, 10 Dec 2009 13:24:53 +0000 (GMT), Jim Lesurf
wrote:

In article , Arny
Krueger
wrote:


Because of the LP format's inherent technical failings, digitizing LPs
is not all that challenging of a task for even an one of those on-board
audio interfaces that comes with most motherboards.

In principle it is slightly complicated because of the possibility of
unpredictably high peaks. But in practice this doesn't seem a problem in my
experience and 16bit samples should be fine if you allow for enough
headroom when setting the gain.


The unexpectedly high peaks are invariably ticks and scratches, and it
really doesn't matter if they overload - they need removing anyway.

d

Sound card for recording
 

"Don Pearce" wrote in message

On Thu, 10 Dec 2009 13:24:53 +0000 (GMT), Jim Lesurf
wrote:

In article
, Arny
Krueger
wrote:

Because of the LP format's inherent technical failings,
digitizing LPs is not all that challenging of a task
for even an one of those on-board audio interfaces that
comes with most motherboards.

In principle it is slightly complicated because of the
possibility of unpredictably high peaks. But in practice
this doesn't seem a problem in my experience and 16bit
samples should be fine if you allow for enough headroom
when setting the gain.

The unexpectedly high peaks are invariably ticks and
scratches, and it really doesn't matter if they overload
- they need removing anyway.

That agrees with my experience. The LP format has a serious problem with
dynamic range, if you define dynamic range as the difference between the
noise floor and the largest relatively undistorted signal related to music
or speech.

If you define dynamic range as the difference between the noise floor and
the largest instantaneous value, no matter how irrelevant to the music or
distorted, then the LP format might have less deficient dynamic range.

We've been in a similar place around here just lately. People have lately
gone on record as demanding sufficient headroom to play back fairly
improbable but rarely observed signals whose samples are all less than FS
but in combination can trick a reconstruction filter into creating an analog
signal that significantly exceeds FS.

I'm not buying either situation as being one that needs to be pandered to.

Sound card for recording
 

In article ,
Don Pearce wrote:
On Thu, 10 Dec 2009 13:24:53 +0000 (GMT), Jim Lesurf
wrote:

In article , Arny
Krueger
wrote:


Because of the LP format's inherent technical failings, digitizing
LPs is not all that challenging of a task for even an one of those
on-board audio interfaces that comes with most motherboards.

In principle it is slightly complicated because of the possibility of
unpredictably high peaks. But in practice this doesn't seem a problem
in my experience and 16bit samples should be fine if you allow for
enough headroom when setting the gain.


The unexpectedly high peaks are invariably ticks and scratches, and it
really doesn't matter if they overload - they need removing anyway.

But if you overload the analogue section with a tick etc isn't there a
chance it will effect the prog material immediately afterwards?

--
*Ever stop to think and forget to start again?

Dave Plowman London SW
To e-mail, change noise into sound.

Sound card for recording
 

"Dave Plowman (News)" wrote in
message
In article
, Don
Pearce wrote:
On Thu, 10 Dec 2009 13:24:53 +0000 (GMT), Jim Lesurf
wrote:

In article
, Arny
Krueger wrote:


Because of the LP format's inherent technical
failings, digitizing LPs is not all that challenging
of a task for even an one of those on-board audio
interfaces that comes with most motherboards.

In principle it is slightly complicated because of the
possibility of unpredictably high peaks. But in
practice this doesn't seem a problem in my experience
and 16bit samples should be fine if you allow for
enough headroom when setting the gain.


The unexpectedly high peaks are invariably ticks and
scratches, and it really doesn't matter if they overload
- they need removing anyway.

But if you overload the analogue section with a tick etc
isn't there a chance it will effect the prog material
immediately afterwards?

There's a chance the sky will fall. How many sky supports do you keep on
hand? ;-)

In general, modern gear recovers from overloads pretty fast.

If you've got an exceptional case, you can determine that pretty quickly by
looking at the digitized file.

Sound card for recording
 

In article , Arny
Krueger
wrote:


We've been in a similar place around here just lately. People have
lately gone on record as demanding sufficient headroom to play back
fairly improbable but rarely observed signals whose samples are all
less than FS but in combination can trick a reconstruction filter into
creating an analog signal that significantly exceeds FS.

The distinction between that and clicks on an LP is that there is no need
to 'trick' the reconstruction filter and nor does it require the disc to be
physically damaged as in the case of 'clicks' from an LP. The excursions
above 0dBFS arise because the recorded waveforms include them. They are
part of the recorded waveform, not a 'trick' or the result of physical
damage.

So the word 'trick' in this context is misleading and inappropriate, and
the LP and CD cases are not similar in cause. One behaviour arises due to
physical damage and makes the required waveform unrecoverable. The other
can be a result of the required waveform defined by the series of samples
recorded on a correctly produced and physically undamaged disc. The
required waveform may still be defined by the series of samples even if a
given DAC can't cope with reproducing that.

The behaviour (requirements for some peaks above 0dBFS) arises as a
consequence of the Sampling Theorem and basic Information Theory. The
series of samples correctly define the waveform to be reconstructed, as per
the Sampling Theorem. Although some test waveforms show extreme examples
of this, required excursions above 0dBFS can occur for commercial
recordings of music. This is not due to any damage equivalent to an LP
being scratched, but a part of the data on the CD. if you check some
pop/rock CDs you can probably find examples without trying very hard.

I'm not buying either situation as being one that needs to be pandered
to.

The main way I "don't buy it" is to avoid buying rock/pop CDs that have
been affected. :-) Alas, you may not know until you have one of the CDs.
So I (and I assume many others) do have CDs where the provided samples
require the reconstructed waveform to exceed 0dBFS between some samples.
What is then unclear is what individual CD players make of this when they
try to reconstruct the waveforms from the data.

Since this is being xposted to a group I don't normally read it may be
helpful for readers there if I give a couple of URLs that examine these
matters in case they haven't encountered this issue previously.

http://www.audiomisc.co.uk/HFN/Clipp.../clipping.html

Shows some examples of one way this can occur with real commercial CDs

http://www.audiomisc.co.uk/HFN/OverTheTop/OTT.html

Examines the effect in detail. Examples show around +2dBFS for commercial
CD, and then an extreme case test waveform.

The important points here a

1) That the effect examined on CD arises a consequence of using sampled
data. So is an aspect of digital information methods for purposes like
recording audio waveforms.

2) That it can arise as a result of what was recorded, not because of a
situation like an LP being scratched.

3) If the DAC and reconstruction filter are correctly designed they would
reproduce the defined waveform correctly, including the parts above 0dBFS,
whereas a scratched LP would be reproducing the effects of damage.

Note also that this has been discussed in AES papers, etc. And I know that
the BBC (sound radio) people tend to keep down the max sample levels on R3,
etc for similar reasons.

FWIW I'd agree that this *should* be a non-issue in practice, *if* CD
makers ensured they kept down the recorded sample levels to avoid
intersample peaks above 0dBFS and/or if DAC makers ensured they played
waveforms above 0dBFS without distortion. However I'm far from sure that
both these provisos are universal. Certainly I know of both CDs and DACs
that fail to meet these conditions.

Given the large dynamic range of 16bit CD it would be easy for pop/rock to
avoid peaks above 0dBFS. But alas the pop industry obsession with
'loudness' seems to drive them to the maximum they can manage.

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

Sound card for recording
 

On Thu, 10 Dec 2009 15:44:21 +0000 (GMT), "Dave Plowman (News)"
wrote:

In article ,
Don Pearce wrote:
On Thu, 10 Dec 2009 13:24:53 +0000 (GMT), Jim Lesurf
wrote:

In article , Arny
Krueger
wrote:


Because of the LP format's inherent technical failings, digitizing
LPs is not all that challenging of a task for even an one of those
on-board audio interfaces that comes with most motherboards.

In principle it is slightly complicated because of the possibility of
unpredictably high peaks. But in practice this doesn't seem a problem
in my experience and 16bit samples should be fine if you allow for
enough headroom when setting the gain.


The unexpectedly high peaks are invariably ticks and scratches, and it
really doesn't matter if they overload - they need removing anyway.

But if you overload the analogue section with a tick etc isn't there a
chance it will effect the prog material immediately afterwards?

A very small one I would have thought. I can't remember the last time
I saw a circuit that didn't simply follow the waveform out of
limiting.

d