From: "Wayne Brissette" <>
>
> Walter Knapp on 12/25/03 at 20:33 stated:
>
>
>>I note that the level meters on most current recorders are LCD and could=
>>be a problem. Don't have a good solution, for the highly visually
>>impaired something like the metering on the Sound Devices MP2 would be
>>good with it's bright multicolor LED's. But going that route is
>>expensive. My portadisc has a lighted meter of good contrast, but again,=
>>it's expensive. Metering is key to this stuff, so a solution would have
>>to be found.
>
>
> One other note about LCD, and LED meters for that matter, they tend to be
> less accurate than analog meters. Depending on what you are doing, this
> may or may not affect your work, but it is something to keep in mind.
> Also depending on the gear/vendor it's possible with analog meters to get
> Peak meters (PPM) instead of the standard VU meters (RMS where 0 dB =3D +=
4
> dBm).
>
> Wayne
Having used both analog and LCD/LED meters in my long history of
recording I'm not so sure I'd say analog were all that good. Especially
consistency over the long haul in the sort of meters found in portable
gear. I've found that the digital metering system is much more
consistent over time than any analog I used. Most portable
analog/mechanical meters are a compromise as the really sensitive meters
are also really sensitive to damage in field use. We are talking nature
recording here, not studio use.
There was a metering found on some really old equipment I did like. That
was a vacuum tube "wink" display. Not sure what the correct term was for
those, used to know. Those displays are long gone. They avoided delicate
mechanical meter movements and were highly reliable. Except that the
tube needed lots of power, it would be a good field meter.
You do have to check what your LCD/LED meters are telling you. Even the
consumer MD's LCD displays have exact calibration points. Few bother to
even find out what those are.
As far as peak vs averaging types, there are both in LCD/LED meters.
Often they are combined, like in my Portadisc where peak metering is
something I can switch on as a overlay on the regular meter. Again, you
have to take the trouble to understand what type of meter you have to
use it effectively.
What type of meter you have is far less important than how well you
understand it and how to use it. The errors I see in metering would not
be prevented by using a analog meter. They can be prevented by
understanding your recording system and using it appropriately.
One of the unfortunate things is that metering is still stuck on
standards that were appropriate for and designed around analog magnetic
tape and mechanical meter design. It would be nice to see metering
indications that were appropriate for digital. Too many people are still
metering like they were doing analog. If we can't change them, then
maybe the scaling on the meters can be changed. And then we get into the
question of why many digital meters are set up to imitate the dynamics
of the mechanical movements on old analog meters. The limitations of
those mechanics were not some ideal, only what could be achieved. And in
practice very variable.
And, to get back to the visually impaired, which is what this thread is
about, I would say that the typical analog meter with it's dancing
needle would not be better for the visually impaired than good LED
metering. Even LCD would be better than a fine needle. Particularly
illuminated LCD displays.
Walt
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