Why do digital scanners sound terrible

[KC0CSE]

Originally Posted by pepsima1

Well you can't even buy a cheap scanner really anymore. All of the stock of cheap scanners are dwindlwing because there are no new companies making any of the scanner lines right now. Uniden is still making the bcd396xt/996xt but they are pretty much junk anyways but thats pretty much all we got right now. Digital has been pretty crappy but they say that there are some newer firmwares out there right now, but some still have troubles. GRE is out of business for the time being. All of their models are selling for high prices on ebay and amazon and they are not worth the hijacked prices.

Just move over to the commerical side and buy a nice Motorola handheld and program it yourself and learn. But you might pay double or triple for a nice radio and you have to spend the time researching and figuring out on how to program them. Worth the time I do say so. They sound so awesome and thats the way a radio should sound. Just my 1 cent of opinion.

Ok I ready for a Moto which one would you recomend? KCMO has P25 800MEG...simulcast is driving me crazy...ready for a "clean" sound....

[mmisk]

I agree with you about the sound quality of digital communications signals. Unless the radio is line of sight to the tower, it is terrible.
While digital is great for an un-compressed high sample rate music file that is on your computer, it leaves much to be desired for narrow band radio communications, especially if it is compressed. The slightest noise on the signal and you lose voice quality right away. It is the worst thing they ever did for emergency communications.
An analog narrow band FM communications signal can still be understood by the human ear even if it is extremely noisy. That is the amazing thing about the human ear. However, with narrow band digital comms, the slightest bit of noise, and chunks of the voice are cut right out. So emergency services now have a sub standard radio system. The manufactures will say digital is better, but with a noisy signal it is far worse resulting in very unreliable communications.

[kg4pbd]

Originally Posted by pepsima1

Well you can't even buy a cheap scanner really anymore. All of the stock of cheap scanners are dwindlwing because there are no new companies making any of the scanner lines right now. Uniden is still making the bcd396xt/996xt but they are pretty much junk anyways but thats pretty much all we got right now. Digital has been pretty crappy but they say that there are some newer firmwares out there right now, but some still have troubles. GRE is out of business for the time being. All of their models are selling for high prices on ebay and amazon and they are not worth the hijacked prices.

Just move over to the commerical side and buy a nice Motorola handheld and program it yourself and learn. But you might pay double or triple for a nice radio and you have to spend the time researching and figuring out on how to program them. Worth the time I do say so. They sound so awesome and thats the way a radio should sound. Just my 1 cent of opinion.

Actually I'm very happy with the sound quality on our local P25 simulcast system. I've adapted to the reality that I have to leave the scanners in a cabinet on a pair of yagi antennas. So I have multiple private streams I can dial into from my phone. I miss being able to reliably use a radio portable but this works. And the voice quality is very good. As far as using a Moto radio, how do you do that on a trunked system?

[Boatanchor]

I regularly monitor Conventional and Trunking P25 on a variety of 'high end' radios as well as scanners.
To my ear, there is actually little difference apart from the $1500+ radios having more audio grunt & better speakers.

People need to remember that Phase 1 (IMBE) is 10 year old technology.
P25 phase 1, even under low BER conditions, introduces unpleasant audio characteristics into the human voice and even worse characteristics to any ambient noise that also happens to make its way through the TX audio chain to the vocoder.

Basically, Phase 1 is well and truly obsolete and the only reason it is even still being sold at all is because of the huge vested interests from the likes of Motorola who have roughly 80-90% of the P25 Public Safety radio market.

If State administrators realized that you can buy a >1000ch, 45w, AMBE2++ (latest vocoder), DMR radio for less than $700 and a two slot, TDMA DMR repeater for less than $2500 and the DMR radio offers much better audio quality, twice the channel capacity in the same bandwidth and comparable range to P25, P25 would very quickly turn into the BetaMax of the radio world.

[car55]

Originally Posted by Boatanchor

I regularly monitor Conventional and Trunking P25 on a variety of 'high end' radios as well as scanners.
To my ear, there is actually little difference apart from the $1500+ radios having more audio grunt & better speakers.

People need to remember that Phase 1 (IMBE) is 10 year old technology.
P25 phase 1, even under low BER conditions, introduces unpleasant audio characteristics into the human voice and even worse characteristics to any ambient noise that also happens to make its way through the TX audio chain to the vocoder.

Basically, Phase 1 is well and truly obsolete and the only reason it is even still being sold at all is because of the huge vested interests from the likes of Motorola who have roughly 80-90% of the P25 Public Safety radio market.

If State administrators realized that you can buy a >1000ch, 45w, AMBE2++ (latest vocoder), DMR radio for less than $700 and a two slot, TDMA DMR repeater for less than $2500 and the DMR radio offers much better audio quality, twice the channel capacity in the same bandwidth and comparable range to P25, P25 would very quickly turn into the BetaMax of the radio world.

Are you saying radios the department uses are doing the same thing??? It is hard to believe any department would move to digital system if that was the the case.

[hertzian]

What about two-way manufacturers tweaking the P25 "standard" to their liking, and scanner manufacturers having to abide solely by the standard, or pay hefty proprietary licensing fees for the "tweaks", assuming that it even possible to license the tweaks in the first place?

Or am I just a conspiracy-theory nut. Probably.

[car55]

Like I say I have new smart phone and it does not come in harsh , muffled or artificial voice .

So don't know why it like that with scanners.


Also I don't how how Rebanding will work has it could also make communication sound terrible for scanners.


Here is Atlanta fire radio Motorola how it sounds on a digital system .
Tyler Perry studios fire radio traffic - YouTube

[rak313]

Originally Posted by car55

Like I say I have new smart phone and it does not come in harsh , muffled or artificial voice .

So don't know why it like that with scanners ....

Your smart phone likely has a much newer - better performing - higher bit rate - vocoder. The imbe vocoder is only 4400 bps, and is 10 years old. Much better performing vocoders are available. The typical 2G and after vocoder is around 8-12 kbps and much improved vs 10 years ago. There are even so called "HD" vocoders with 8-12 kbps that have 300Hz-7kHz BW.

I believe choosing the imbe vocoder for Phase 1 P25 was a big mistake. They should have allowed for multiple vocoders - and not specified a (soon to be obsolete) proprietary (and patented) one.

But the biggest mistake is making our firefighters and police cram 2 digital voice channels down a 12.5 kHz channel (phase II), and cry's of - no bandwidth available from the FCC - while 100 MHz frees up in the analog TV band that was sold off for smartphones so our 10 year old daughters can watch "dora - the explorer" while riding in the car.

This is just plain nuts! (yes - I know there is BW in the 700 MHz band for public safety).

Originally Posted by car55

Here is Atlanta fire radio Motorola how it sounds on a digital system .
Tyler Perry studios fire radio traffic - YouTube

I'm nor sure about this link - is it an example of good digital audio from a subscriber radio - or bad scanner audio.

To me - this sounds similar to what I hear on my $20 USB dongle to PC - SDR P25 receiver. Which I characterize as pretty good - as far as copy-able. Not the best - but neither is analog narrow band FM.

I understand - it can be muffled - and sometimes i can't understand what is being said. but i have that problem in person with anyone under 30

[car55]

I'm nor sure about this link - is it an example of good digital audio from a subscriber radio - or bad scanner audio.

To me - this sounds similar to what I hear on my $20 USB dongle to PC - SDR P25 receiver. Which I characterize as pretty good - as far as copy-able. Not the best - but neither is analog narrow band FM.

I understand - it can be muffled - and sometimes i can't understand what is being said. but i have that problem in person with anyone under 30

That audio may not be the best but way better than what a scanner can pick up and closer to analog.


This just terrible really terrible.
Police Radio Transmission - Phoenix PD Kidnapping Pursuit

Police Radio Transmission - Phoenix PD Kidnapping Pursuit - YouTube


Merry Christmas, LAPD Styl


Merry Christmas, LAPD Style [HD] - YouTube

LAPD Scanner Audio Crenshaw Mall Shooting Southwest Division

LAPD Scanner Audio Crenshaw Mall Shooting Southwest Division - YouTube


I can't see any department would go to digital system if this is what sound like.


Anyone called or e-mail Uniden ?

Any new scanner coming out this year or next year that may fix this problem?

[teknishun]

The secret to clear sounding audio on a DIGITAL channel is a GOOD ANTENNA. You MUST deliver a good strong signal to the receiver. A weak or poor signal causes data dropouts. You should buy and install the best OUTDOOR antenna you can afford and place it as high as feasible for your location. If all you are using is the rubber duck antenna that came with your scanner then what you will hear will sound like robot R2D2 or pure gibberish at times, garbled speech, unintelligible voice, etc. Bottom line - GET A GOOD OUTDOOR ANTENNA. I have listened to digital radio transmissions using the "real" police and EMS radios that the pros use in the field, and with the proper antenna system they sound just as crisp, clear, and natural sounding as the old out-dated analog!