Setting USB audio interface input level

[Al, Cambridge, UK]

I'm looking at USB audio interfaces, but I'm puzzled that very few
appear to offer any indication of input level beyond a simple red
light when the ADC overloads - and many don't seem to offer even that
much.
Am I overestimating the importance of this feature?

I'm currently using a small Behringer mixer + Edirol UA-1EX (into
Cubase Essentials 5 on a laptop), but it's difficult to set up the
levels so the mixer's VU meters give an accurate measure of the
convertor's input level.
Is there a better way to set this up beyond trial & error?

Thanks for any help with these questions.
Al

[Soundhaspriority]

"Al, Cambridge, UK" <big...@bigfoot.com> wrote in message
news:abf60335-0d0d-4bb2...@k19g2000yqc.googlegroups.com...

Al,
The crudity of the indicator is because, customarily, the level is
measured on the digital side. The software looks at the numbers the A/D puts
out. 0dB is indicated by the magnitude of a 16 bit signed quantity.
Most converters above entry level are bundled with a small applet that
provides a large, readable bar meter display. However, this is not
necessary. All recording software provides metering of the input level.
Focus on those indicators, not the metering on the gadget.

Bob Morein
(310) 237-6511

[Scott Dorsey]

Al, Cambridge, UK <big...@bigfoot.com> wrote:
>I'm looking at USB audio interfaces, but I'm puzzled that very few
>appear to offer any indication of input level beyond a simple red
>light when the ADC overloads - and many don't seem to offer even that
>much.
>Am I overestimating the importance of this feature?

Depends. Most people are watching the metering on the DAW.

>I'm currently using a small Behringer mixer + Edirol UA-1EX (into
>Cubase Essentials 5 on a laptop), but it's difficult to set up the
>levels so the mixer's VU meters give an accurate measure of the
>convertor's input level.

That's because the "VU" meters and the peak meters on the DAW are measuring
different things and they are not comparable. And the meters on the Behringer
aren't even real VU meters.

Good, accurate metering is very expensive. This is what keeps guys like
RTW and Dorrough in business. And it's the reason why folks use the metering
on the DAW.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Cyberserf]

Al,

IFAIK, there are two options...the Edirol should come with a software
mixer that has a meter bridge, once you set your levels, there isn't
much reaon to expect they'll change. Conversely, as Bob suggests, you
could press F3 and use the input meter bridge in Cubase.

Cheers, CS

[Al, Cambridge, UK]

Thanks everybody for their help; it has helped my understanding.

Unfortunately the Edirol UA-1EX only has a single input activity (not
clip) LED on the unit itself, and its software doesn't include a meter
display.

I'm a bit surprised that the Cubase channel meters don't show a clear
indication of overload and I'm suspicious that I'm able to adjust the
track's input level in software - as far as I can see, I could adjust
that to be very low but the ADC would still clip. The transport window
shows a red flag above its minature meters when the input overloads,
which you click on to reset - it's a pity that I can't get something
similar on the channel itself.

I'm planning to find a more sophisticated USB interface with mic &
instrument inputs, so I think I've got some more ideas of what I need
to look for.

Thanks again,
Al

[Mike Rivers]

Al, Cambridge, UK wrote:

> I'm a bit surprised that the Cubase channel meters don't show a clear
> indication of overload

They don't? Whadd'ya want? Flashing lights and bells? When the meter
hits the end, that's too much. What you don't have an indication of, and
this is true of any software program (and unfortunately some hardware,
too) is that you don't have an indication of analog overload.

> I'm suspicious that I'm able to adjust the
> track's input level in software - as far as I can see, I could adjust
> that to be very low but the ADC would still clip.

This is a problem everywhere, and one that manufacturers tend to ignore
on the assumptions that:

(1) You'll be able to figure out that's happening from the sound, or at
least
the clipped waveform when you know that the meters were running in a
safe range (most hand-sized recorders have this problem)

and

(2) You'll have what it takes to deal with it - an attenuator on the input
that's coming from something else.

This is all about system engineering, and unfortunately it isn't automatic
and one-size-fits-all. The problem is compounded by the manufacturers
being forced to keep costs as low as possible. An extra dollar would put
in a suitable attenuator and maybe even an adjustable level control, but
that would put them in a non-competetive spot in the market. Too many
customers don't see the need for that extra switch or knob and don't want
to pay for it.