# Re: How do I tell which A/D Converter is better

"Mike Rivers" <mrivers@xxxxxxxxxxx> writes:

Matthias wrote:

If I have 2 A/D Converters, let's say sampling rate 44.1 kHz, 16 Bit
resolution, how can I really TELL which one's the better one ?

Record the same thing throug each one, play back your recordings
through the same D/A converter, and listen for differences. Unless one
of your A/D converters is really bad, I suspect that you won't be able
to hear a significant difference, but if you do, then, you'll be able
to tell which one you like better - and that's what counts.

And, probably in addition to the above (just cam in mind while writing
this), I can 'imagine' that 20 Bt is better than 16 - but how to 'prove'
it (to myself .....) ?

The classic demonstration is to reduce the record level by about 65 dB
below normal, then boost the playback level back to where you can hear
it. While you should never do this in practice, it will give you a
sense of what happens at low levels where you're down close to the
limit of resolutin of the converter.

Is this all done 'by ear' (which would assume, that I have THE ears) or
can I 'measure' this in some magic way ?

Generally, measured numbers look so close that you can't really tell
one from another.

Listening is the best way in the end.

But also, you should do some diagnostics as listed above to make sure things
are working. Here is another one: Record a single sinewave (eg., 1600Hz) onto
a computer file or CD. Play it into the ADC and record. Then do a Fourier
analysis and look for harmonics (distortion) at multiples of the base
frequency. Only the base frequency should be present.

Try this at different input levels, both very low (as above) and near full
scale (just under 0dB). I've noticed fairly large distortion (eg., 1% THD,
harmonics -20dB down) on some ADCs. They're obviously broken. As with
computers, assume something is broken until you can confirm it works!

Richard
.

## Relevant Pages

• Re: How do I tell which A/D Converter is better
... resolution, how can I really TELL which one's the better one? ... Record the same thing throug each one, play back your recordings ... through the same D/A converter, ... to hear a significant difference, but if you do, then, you'll be able ...
(rec.audio.pro)
• Re: OT: New low for Microsoft!
... > and computers that are around now are overpowered, ... In which case I DO "want" to be able to play the latest greatest games ... 21" monitor I can play at a resolution above 640*480. ... Which is play those games. ...
(Fedora)
• Re: Potentially Worrying Gulf Envoys
... You also need to install BG2 if you want to play the Tutu mod. ... (when I finish the vanilla game I can begin the expansion)? ... Patched versions of Quake and Quake 2 look really good and play well as they can be made to run at the native resolution. ...
(uk.games.video.misc)
• Re: help please: audio synch problems
... The play fine on my PC in perfect audio synch. ... Anyway how I got it fixed was to first use Xilsofts Video ... Converter to change just the frame rate to 29.9 on the Xvid's and then DVD's ...
(alt.video.dvd)
• Re: product that will record off the air tv onto a hard drive?
... satellite tv programs onto a digital digital hard drive and then play ... play onto a tv set that does not need a monthly subscription to TiVo ... converter box, but using it is cumbersome with the equipment I have. ... It depends what country your living in. ...
(rec.video.desktop)