Martin,
The most telling difference between V1 and V2 software, with respect to
transmit audio quality, can be observed using an external receiver and
an Audio Editing program such as Cool Edit or Adobe Audition.. Viewing
the recovered waveform of normal speech on V2 reveals a distinctively
clipped waveform that is very different from V1.
No amount of input level manipulation or gain adjustment on the Orion
can make it go away, which seems to indicate that this is happening
someplace after the first audio amplification stage. Quantifying this as
a "measurement" of some kind is a bit tricky, but I can assure you that
the results are quite audible. For all of science's sophistication with
measurement techniques, nothing accurately quantifies the audible
effects of clipping. What IS known is that optimal interstage audio gain
structure can completely eliminate it. As a general rule, an audio
circuit will typically allow at least 10db of headroom between the
nominal operating level and the clipping point. That number can vary
considerably, depending on what the intended function of the circuit is
and whether or not the dynamic range of the input audio has been
modified prior to application.
My guess is that we have an audio stage being run too close to it's
clipping point. This audio stage is controlled in software, and is not
user adjustable. The increase of sensitivity with respect to levels on
both the microphone and auxiliary inputs seem to support this theory.
73,
Mike
NM7X
-----Original Message-----
From: tentec-bounces@contesting.com
[mailto:tentec-bounces@contesting.com]On Behalf Of Martin, AA6E
Sent: Wednesday, April 05, 2006 9:03 AM
To: Discussion of Ten-Tec Equipment
Subject: Re: [TenTec] The Bug
I don't have an opinion about O2 sound vs O1 (V1) or O1 (V2), but I would
like to see measurements instead of comments like "not robust". I haven't
got a clue what robust sound is!
73 Martin AA6E
On 4/5/06, Toby Pennington <toby423@earthlink.net> wrote:
I haven't heard a really good sounding O2 yet. OK, Yes, but not like the
robust audio coming out of the V1 firmware on the Classic Orion. Toby
W4CAK
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