[App_rpt-users] Repeater Audio?

[Alan Adamson]

isn't exactly Allstar related, but sorta.

I've got a challenge that I'm not sure how to resolve.

I think I've said this prior.  I've successfully glued an RTCM to a New Icom
NXDN repeater.  This repeater is running in mixed analog mode and the
Allstar is gated to analog only.  There is no external controller running
other than the RTCM.  The internal controller functions when there is a
digital signal and that doesn't come across allstar.  For now that's an
issue I'm willing to accept on that repeater.   By using the Disc Out and
the Mod in, this setup sounds *awesome*, I'm just blown away at how good it
all sounds end to end.

I'm about to head down this path on a second repeater, but this one I want
to bring up as either Digital only or mixed digital.  The controller has the
above mentioned Disc out, but that only works with an analog signal.  To get
*transcoded * audio out, you have to use a pin called AF OUT, it's fixed
level, but it's not discriminator, at best it sounds like speaker level.
This is the only way to get an intelligent audio signal to feed to allstar
when running in digital mode, there is no equivalent of discriminator out
when in digital mode.

Because I'm using an RTCM, I also can't *process the audio* or at least it's
not obvious.  And putting that audio back out into the network, it sounds
really bad.  it's too bassy, and muddy, basically it's de-emphasized and it
really needs to be pre-emphasized.  Is there any way with an RTCM to tell
anything that I've got de-emphasized audio and to help it out?  (it really
needs some form of low pass put on it and the mid/high frequencies boosted).
Also for note, I'm running my RTCM in conventional mode, not voter mode. and
I have a CTCSS gate that is valid with COR *AND* CTCSS (in digital in NXDN
they call that RAN codes).

So I either need to filter between the radio and the RTCM or in the Allstar
code if possible.

BTW, I really have the same problem coming the other way, FM audio coming
from Allstar and being then digitized to NXDN digital (AMBE+2 for those that
want to know) *can* sound *really* good, but can also sound really crappy.
If the person on the talking end is mumbling, or has a very deep voice, it
doesn't sound worth crap, if on the other hand the person has a bright voice
and talks clearly, it sounds amazing.  This has nothing to do with the
*emphasis* of this audio, it's FLAT going into the discriminator, the radio
from there handles the transcoding.

So, as a start, I'm looking for a relatively easy (and cheap) way to take
speaker quality audio from the repeater and put it out *improved* on allstar
with a RTCM.  Note, with a URI, I could do that, but I don't seem to know
how if possible with the RTCM/Voter/Rpt.conf stuff. 

Anyone faced a similar challenge and found an acceptable approach?  I
thought about trying one of the CAT audio boards, or maybe building a 3 or 5
band graphic equalizer, but I can't be the only person who's had this issue
and solved it?

Thanks in advance, and let me know your thoughts.

ps. I'm happy to give anyone a demo, just let me know and I'll reconfigure
my repeater for digital and show you. I'm testing some analog stuff at the
moment, and the new repeater is setting on my floor currently.

Alan
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