High Pitched Voices On Digital Question

[snerd]

There is a female who works dispatch, alternating between police and sheriff dept. Her voice is very high-pitched, nasally, almost whiny sounding. It makes understanding her very hard sometimes. It seems as though some of her higher-pitched tones make the reception stutter. I messed with my antenna and locations around the house for a week lol, and realized it's probably her voice, as others are okay. I would assume there is no setting that could help with this?

 

[jtwalker]

Maybe a high quality external speaker. I am not aware of any settings on the scanner.

 

[RFI-EMI-GUY]

I have had a lot of trouble understanding the dispatchers on our local system. I use the replay feature a lot. Sometimes a unit will come in so clear you will think it was analog. But mostly the audio has a mushy sound. I don't think it is simulcast distortion even though I have a BCD536HP.

Yesterday even the dispatcher was asking a unit to repeat.

I think the audio settings on the portables is way off, a lot of variability. In my opinion P25 audio is pretty damn awful. For comparison, I recently tested some 1990's Securenet (12 KBP/s DES, CVSD) and they sounded much better. P25 (Astro) was supposed to improve encryption over the Securenet. I think they missed the target. Yes, I know IMBE was not Motorola's decision, they pushed VSELP.

 

[snerd]

There are times when she will speak clearly, slowly into the mic, and it is much better. I think they just need some refresher training lol

 

[GlobalNorth]

My agency once hired someone with a significant hearing impairment to be a dispatcher. He was a nice person, a diligent employee, but the guy could not speak clearly to most of the listening audience. They had to move him out of radio because he just couldn't perform the job satisfactorily.

 

[RoninJoliet]

You guys got it right, seems some PD's have been given cheaper equipment with shrill sounding mikes and mushy audio, audio was much clearer on VHF-UHF back in the day if the signals were good

 

[RFI-EMI-GUY]

They are speaking too quickly as well. I wonder if the vocoder expects this fast of cadence?

 

[RFI-EMI-GUY]

My agency once hired someone with a significant hearing impairment to be a dispatcher. He was a nice person, a diligent employee, but the guy could not speak clearly to most of the listening audience. They had to move him out of radio because he just couldn't perform the job satisfactorily.

Having a "radio voice" should be a requirement. No discrimination, you just need to be heard.

 

[snerd]

I should check into it.............. I've been told I have a face for radio lol!!

 

[snerd]

And the Fire Tone Out sound on digital lol!! I've heard better on a fully-compressed ham radio signal!

 

[Ubbe]

Most digital systems doesn't use vocoders that transfer the exact voice data bit for bit from one end to the other, like a compressed zip kind of function. They use algorithms that strip away a lot of data bits and at the other end the algorithm tries to guess what bits have been removed and tries to restores them as best as it can following the rules in the algorithm.

The algorithms are dependent of the voice quality and if it doesn't "match" it will sound awful. It's impossible to transfer pure tones in a digital system as they will sound harsh and very distorted due to the algorithm that are not optimised for that kind of sound.

/Ubbe

 

[IAmSixNine]

Also Most radios, (Motorola for sure, maybe kenwood) have the ability to adjust the audio profile and give bass and treble adjustment as well as how the P25 decoding is handled. Sure this is on the Rx side but there are also mic gain and other adjustments on the TX side in the profiles.
There was a multi city radio system that was new, this was about 4 years ago and it was plagued with issues from the first day it went live. Radios sucked.
4-6 months into it on a fire dept ops channel they were testing radio profiles from various fire depts in the metroplex and there were noticeable differences in audio quality. Factory is OK but you can go in and tweak the audio on commercial radios to make them sound much much better.
A system that has been tweaked is nice to listen to. You can even have different audio profiles based on if your police, fire, ems, sanitation and if your radio uses a speaker mic or not.
This fire dept tested audio in normal environment, then next to an engine pumping water, then with a facemask on. First was their factory default test, then test with 1 neighboring dept on a different P25 system, then another on a different P25 system, and one from a UHF conventional fire dept that used APX radios.
While listening i could immediately tell a difference in all of them. And all of them were better than the factory.

 

[Ubbe]

And all of them were better than the factory.

I've probably programmed over a thousand digital radios over the years for systems in different countries and one huge problem are economical, that the sales department wants a system delivered asap to receive their bonuses for that quarter. Sometimes parts or software functions are missing at delivery or configurations have not been tested out, but sales do not care about it as it will be the after sales department, that has another account, that will fix it.

So most systems will work bad at delivery until all configurations have been sorted out. In later years profiles are used in radios but are a manual selection that the user has to do, and most of them will not bother. So I try to find a general setting that can be used in most places. One thing to avoid are too much mic gain and any kind of noise reduction features that will only distort the voice quality and the AGC also needs to be carefully set.

Most radios have seperate settings for the internal mic and speaker and the external audio gears. Even seperate setting for different kinds of external audio gear like speaker mics and headsets of different kinds, each one with its own audio profile settings. It's a myriad of different settings in modern digital radios that needs to be set correctly to make the whole system work with good audio quality. Most often economical reasons will leave those settings at their default values.

/Ubbe