Hi Paul, One has to deal with reality... while you might consider a soft talking person not properly trained, more than a fair number of users don't have a booming voice. In a larger number of cases a little bit of added audio compression/limiting helps resolve the low (higher/soft pitch) perceived volume level difference.
The brain is pretty good about picking a voice from background audio so just being able to hear the receive audio better is going to help. I've got racks and racks of many brands of audio processing gear available for testing... but you don't need that when a little more/higher audio drive level to the repeater transmitter section will hit the limiter/compressor "harder". Doesn't take much and things can quickly get out of hand (excessive compression/limiting) if you get greedy. So don't get greedy... I like about 6dB of audio compression... some of my broadcast audio friends who are also Hams can hear and tell me when the audio crunches approaching 10dB (which amazes me their ears are that good) so it's my opinion 10dB audio compression is too much in most situations. The ease of monitoring a local repeater during club activities is very much improved with a small amount of main transmitter limiting/compression. The disparity in perceived loudness is greatly reduced when you don't have to reach for the volume control (knob) so often. cheers, s. > "Paul Plack" <pl...@...> wrote: > > Skipp, I generally agree, but it's not the fault of the user's voice. It's a > lack of training in mic technique, sometimes combined with audio circuits > that aren't easily user-accessible. Compression on the repeater eliminate's > the user's need to get things right at the source, and one day, he's going to > need to operate simplex. > > I've worked with broadcast compressors for many years, and agree they could > play a useful role in repeater audio chains. But I always wanted to design > one that was a little different, and digital control of an analog signal path > seems like a good candidate. > > Specifically, I'd like to have something like a compressor with very fast > attack and infinitely long release, immediately dropping gain as needed to > accommodate voice peaks, but not releasing until COS dropped. This would > essentially set the audio gain individually for each user at the start of a > transmission, without any ongoing compression to create the obnoxious > "pumping" artifact we all know and hate. > > The downsides would be additional background noise before the first syllable, > and difficulty in distinguishing users with low audio from users with > inadequate signal strength. Both would feature increased background noise as > a symptom. Then again, IRLP users hand out S-meter reports from a thousand > miles away, so maybe it doesn't matter...(sigh) > > Just running the audio gain 6-10 dB hotter into a fast limiter still allows > great disparity in perceived loudness, but at least the guys with low audio > can be heard. > > 73, > Paul, AE4KR > > ----- Original Message ----- > From: skipp025 > To: [email protected] > Sent: Sunday, August 09, 2009 9:07 PM > Subject: [Repeater-Builder] An advocate for a little audio compression > > > ...a number of operators don't seem to have voices that > drive their radios with adequate audio...Consider 6 to 10dB of audio > compression in your repeater system... > > > . >
