Digital Audio

[GregOH]

I never had a two way radio when I was fighting fires. The Navy didn't think it was needed.

 

[radio3353]

I never had a two way radio when I was fighting fires. The Navy didn't think it was needed.

Agreed. When I was a FF (not Navy, civilian) only officers (LT and higher) had radios. But, having every FF equipped with a radio can be a life saver and I am glad that it is now SOP.

 

[GregOH]

Before trashing ANY DIGITAL SCANNER for audio look at the source of the audio.
A radio system sounds no better than how the users of the system operate on it please take the time to watch this 15 minute video and share with your local departments.

Say It Loud and Clear - Two Way Radios - Motorola Solutions Video Library Update (Catalogue)

Clear communications are critical to first responders. Motorola Solutions works with the International Association of Fire Chiefs to develop best practices to maximize intelligibility and overcome background noise on portable and mobile radios.

video.motorolasolutions.com

I agree.
I like digital audio, but there are many things I hear that I don't like which has nothing whatsoever to do with audio quality. Like when some mic's key it sounds like someone smacking two boards together, radios using the "echo effect", a dispatch radio with background noise that sounds like it's coming from a semi truck, and some of the fire paging that's very loud and over modulated.

I've really wanted to play the audio with a separate amp and speaker to increase the volume but I don't think I can handle hearing the things I mentioned above louder than what I hear of them from the radio's internal speaker.

The crappy stuff I'm hearing is the transmitting equipment and is no fault of the scanner that's recieving it.

 

[CanesFan95]

Digital audio sucks.

 

[stwings]

The problem with this and many other technology industries IMHO is the end user is not the focus of the technology. As a end user your expected to conform to what the technology needs and not what the end user needs. First responders may be unable to free a hand to get their "technology" into its optimal performance parameters. I see the same mentality in the computer industry. Engineers live in an echo chamber of their own ideas with like minded people.

Another example of what I'm saying is with Body Worn Cameras. For 20 years we've been trained to avoid the "inside position" standing directly in front of a subject, for officer safety. Now in order to get the best possible video footage we're told to stand directly in front of a subject, precisely where we've been told not to in the past. So which is it?

On the other side of the coin; my county recently went to a P-25 system and to be fair I will say that old habits are hard to break. I hear a lot of voices on air that are clearly not using best practices, not because they can't, but because they have not been sufficiently trained in the capabilities and limitations of the equipment. Just my humble opinion and it' worth everything you paid for it!!

 

[stwings]

It might also be the quality of the current digital scanners we are using. Let's face it--- I imagine a digital system sounds much better on a $3000 or $4000 Motorola portable. Kudos to Uniden and Whistler for refining reception for us "listeners" as well as they did. It's pretty amazing that we receive so many different systems as well as we do. I imagine that if you listening to digital on a "professional" radio, it would be quite a different experience. Or would it ? Perhaps some folks here who are hobbyists but are also exposed to the professional digital arena can comment.

My $8000.00 portable I use at work doesn't perform significantly better that my SDS100.

 

[KC3ECJ]

Digital audio sucks.

Yeah, the limited bandwidth allowed for 2 way radios is too narrow for digital to sound nice.
The technology isn't there yet to overcome this.

Many people have these pie in the sky ideas about digital. Where if the audio levels are garbled or vary in level, "it wasn't set up right", "a properly set up system sounds great!".

Well I've been monitoring several digital systems already, yeah, there's digital radios that sound about as good as digital can do within it's limits, but there are many that don't.

If digital alone was was supposed to solve this, it hasn't.

 

[MStep]

My $8000.00 portable I use at work doesn't perform significantly better that my SDS100.

Best recommendation for the SDS100 that I have seen yet.

 

[RFI-EMI-GUY]

Yeah, the limited bandwidth allowed for 2 way radios is too narrow for digital to sound nice.
The technology isn't there yet to overcome this.

Many people have these pie in the sky ideas about digital. Where if the audio levels are garbled or vary in level, "it wasn't set up right", "a properly set up system sounds great!".

Well I've been monitoring several digital systems already, yeah, there's digital radios that sound about as good as digital can do within it's limits, but there are many that don't.

If digital alone was was supposed to solve this, it hasn't.

I don't think the vendors M and H have wrapped their heads around what constitutes test tone level for P25 systems. subscriber radios run hot and cold and consoles are usually set too hot and sound muffled. in an analog system there was a linear relationship between RX and TX levels. with vocoder there is not.

 

[merlin]

Hands down, the best audio I have heard was an older Orion commercial radio.
It uses an analog processor for advanced filtering and sprouts a 15 watt low distortion amplifier.
Mate that with the 20 watt speaker and sounds great.
Digital is far more complicated. Just in its nature, noise can be reduced 80Db. Digital signal processing adds filtering and for radio, formats any digital protocol in use and decodes the same.
Radio is a two way affair, consider the TX mic, it's immunity to noise then preamp distortion. That all gets digitized.
Put garbage in, you get garbage out. any protocol, won't change that.
Some formats are better at normalizing but still fail the test. The booming voice of a mic eater, then the squeaky voice across the room. add noise in, you get noise out also.
What scanner made has equalizing with the DSP ? (much less normalizing.
Some day, they may go to synthesized voice generated by decoding functions. Til then, you are stuckwith hearing 'radio'.
Cheers

 

[EastCoastSunrise]

I agree with everyone here. When I first started to listen to radios I for some reason always loved to find a digital channel. Yet quickly that wore off and analog became my preference once more. While it may be a range thing or a system configuration I found analog more easy on the ears and I could pick up on speech patterns to understand what's being said. With digital, when its good its good and can sound awesome, but that is uncommon for me to find. Up near me is the Cambridge P25 system, and it sounds awful. Everyone sounds like they are speaking at the bottom of a barrel with a pillow over their face. I thought it was just one or two users at first but noticed that everyone on the system sounded like that. I discovered that when I heard one of their engines calling up on the analog system of a surrounding town. I think that there are improvements to be made to these systems to improve their quality, but analog I think still is superior, and looking at it at the lowest level, analog I think will remain supreme for voice quality.

 

[Rt169Radio]

In my area so far all digital transmissions sound "computery" if that makes sense, I believe it's because of all the extra data that is transmitted along with the voice.

Compared to regular VHF/UHF where all is being transmitted is just voice

 

[chrismol1]

I've got to say digital audio on a real newer commercial subscriber radio, my APX, is amazing compared to just about anything else Ive had especially if you get into the various radio profile settings. Phase 1 P25 audio certainly comes out cleaner compared to an old 10 yr old IMBE XTS with latest firmware or SDR trunk or any of those. The day I first turned on my APX was quite a shock!

 

[buddrousa]

Money talks BS walks

 

[KN4EHX]

I’m personally enjoying the switch to digital. Almost everyone else I work with is transitioning to P25 Phase II on APX NEXT. Changing from VHF and UHF analog systems that are on their last legs - I’m glad to see them go.

The static is terrible even when others are using their mobiles; of course poor antenna choices made by the city and county have a lot to do with that. Even worse on portables.

P25 provides us with clean audio and more talk paths. Sure, the technology will continue to evolve as it isn’t absolutely perfect, but it ain’t bad by any stretch. Furthermore Tennessee uses a statewide system so the more people who decide to join the better the infrastructure will be as more sites are added.

It will be interesting to know what will appear in the next 20 or 30 years.