[arm-allstar] Audio Issue

[Doug Crompton]

David,

 The ideal with any digital system is to achieve the highest level possible
without clipping. Unfortunately with the wide number of users on a repeater
or mass connected Allstar users it is very hard to maintain a constant
level. This is most often a user problem especially with handhelds with
noise cancelling mics. If you get more than a few inches away the level
drops greatly.

The proper way to set the levels is to put a known fully deviated signal
into the repeater with a service monitor and adjust the simpleusb-tune-menu
item 2 for an equal level of deviation. You can also do this with a known
proper deviated radio talking to the repeater in the absence of a service
monitor. It is better to err on the low side as clipping is much more
objectionable than a slightly lower level. I might also add that the PC
iaxrpt's bar graph is also a good way to check the digital level. You want
it to go to no more than about 95% of full scale with any signal and never
to full scale.

Once the input level is set you can set the output level to the repeater
using item 3. This should be set using a service monitor looking at the
output of the repeater.

Doing it in this way and in this order results in fully modulating both the
repeater and the Allstar circuit without over deviation.

We are working on a new channel driver that will off some compression
and/or level control that would help this situation. In the end it is the
individual users responsibility to adjust their levels accordingly.


*73 Doug*

*WA3DSP*

*http://www.crompton.com/hamradio <http://www.crompton.com/hamradio>*



On Mon, Jun 11, 2018 at 11:50 PM, "David via arm-allstar" <
arm-allstar at hamvoip.org> wrote:

> I have a few repeater link node audio level extremely high on allstar
> only. Simply usb tune only adjusts the analog system audio and is good. The
> high output is across only the allstar system on several nodes monitoring.
> Have not found a place to adjust it. Most everyone is fine, but several
> link repeater nodes hurt my ears. It this a wiring issue?
> Thanks David, any info on direction is appreciated!
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