dPMR446 Audio Test - Digital vs Analogue 

DR-100 MKII - MKIII is out now.

@@tdcattech Nice bit of kit....

@@tdcattech Are you going to do a range test on these Motorola's?

Yes. I'll be doing something locally. Probably using the same route as this video ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-t3LZ5CvlQGM.html so I have a direct comparison to a test I've already done. I'll also be including them in a 27km range test I'm due to do with a friend of mine in the next few months. That one needs a bit more planning though.

TDCatTech perhaps compare them with your T80’s in a similar 10km test that you did?

Hi, i just consider between the kenwood 3601D and the motorola xt660. Cant decide. Did you test them? Which one youwould choose? thx

@@RC-Fan Any updates any of you two? :P

@@Micromation not yet :)

Just to chime in, although years later, maybe useful to someone who’s looking into those. I recently got the Kenwood TK-3701D and they are way way better in dPMR than the Motorolas in this video. I hope Motorola updated those at some point. dPMR works so good over few kilometres it’s unbelievable for a 0.5W radio. All crystal clear and practically very low noise floor. Yes some delay but when you’re far away it doesn’t matter. Also tried those in analog with a Baofeng I had lying around and all good and working.

​@@Xpucso far never had a pick up on dpmr in north hertfordshire anyway on my equipped sds100, nor one my sds200 with outside aerial, most seem to use the extra analogue and original analogue

It couldn’t do this automatically, no. Of course, you could always request the other user switch channels to digital but that would kind of defeat the object. In my experience, although digital is frankly awful compared to the possible clarity on analogue, your ear does become attuned to it and you can understand it better. It depends enormously on the speaker. Some voices almost sound as good as analogue. If you have someone who mumbles, you’ve had it!

I use sds 100 and sds 200 and rarely have any issues listening to dmr, dpmr still no users found near me but my local shopwatch, theatre, factories, and even a few vhf farns sound excellent on dmr

I gave audio process issues yet most tx are fine oddly I've heard same on radio bring used and it's not as good as my uniden, so can see that using is difficult I've heard airwave tetra and that I do find hard to understand on the police radios, but somehow they seem to understand, but my mate says sometimes he can't understand, but that happened on analogue as well

I love it when a user switches from analogue to dmr, or even nexedge, much Rarer uk, as to me love listening to dmr

Ans simplex users too less range yes but with my garex I can get simplex dmr from 2 miles or so

DMR and dPMR radios generally all use the same vocoder (AMBE+2). If you used a different vocoder then the radios wouldn't be compatible. So Motorola uses the same vocoder as the Anytone radio you mentioned.

Exactly. I am also from an era of outstanding audio quality (FM broadcasts). I love new tech, but when we take such a distinct (and audible) step backwards, it makes me question those who make spectrum decisions (Ofcom in the UK). It's a shame as these could sound amazing.

You’re right, but in my opinion, the incredibly low bitrate leads to a lack of intelligibility. Particular when you compare it to the analogue equivalent. The other benefits of digital are massive, but, as you say, it's all about communication and digital could be so much better.

Because of the poor quality many public services do not use DMR. CRITICAL COMMUNICATIONS REQUIRE EXCELLENT AUDIO QUALITY. I think Tetra sounds better than DMR.

@@Subgunman The USA uses P25 phase 2 which has the same vocoder as DMR. So you really can't argue that nobody uses DMR because of the audio quality, when P25 phase 2 has the same audio.

@@radiosification I have heard the difference between DMR AND P25. If they use the same Vocoder then why when one listens to the audio produced on an analog radio, there is a massive difference. P25 encoded audio sounds like white noise of an unsquelced radio while the DMR encoded audio sounds like you are listening to fast packet radio? From what I have read they might be using the same vocoder but the algorithm used is far different otherwise a P25 radio will receive DMR audio without a problem. Another issue is there is no "color code" used anywhere in programming the radio data, there is only the NAC code which allows one to access a particular repeater.

​@@Subgunman The vocoder has nothing to do with how it sounds when you listen to the signal in analogue. You can send voice encoded in this vocoder (AMBE+2) over any sort of network. You can send it over the internet or even a dial up connection. Are you sitting here talking about how dial up sounds? Or how the radio channel sounds when you send it over 4G or 5G? No, because it's completely irrelevant. Lots of modes use the same vocoder. Yaesu fusion, dPMR, NXDN. They all use that vocoder too. None of them are compatible because they have different packet structures, signalling etc. Even different modulation. None of them would work with each other because the bits are arranged differently for signalling, maybe they have different forward error correction and so on. If any two digital modes/standards worked with each other, then they're not two different modes -they're the same one. Digital standards are nothing like human language. You have to get it exactly right otherwise it just won't decode, so you can try all you like making a DMR radio talk to a P25 radio or whatever other combination of standards you want, and it'll never work in a million years. Two radio standards can absolutely use the same vocoder and sound the same when decoded without being even slightly similar if you listen to them in analogue.

Agreed. It's horrible. The other digital benefits are numerous but why would audio quality be ignored so much. It's kind of a key part of radio communication!!

We have the same issue with digital comms at my place of work although thats with licensed DMR equipment. the staff have said the old analogue system we previously used was much clearer. mind you I believe the DMR standard was originally developed in the 1990s so what do you expect? and dPMR doesnt seem to be any better either.

Digital undoubtedly has many advantages over analogue. I have never tested it with a noisy background. I assume you're saying that the rejection of background noise is much better. I can see that being a huge plus point for pub and club workers etc. Unfortunately, I can't get over how compressed they decided to make the audio. It's typical spectrum planning. Audio quality is sacrificed over everything else. Yes, I have sent SMS using the XT660d. It's basic and feels like using a mobile phone in 1998, but it works and does the job it was designed to do.

@@tdcattech Thank You for reply, Yes , exactly their codec compress most significant human voice bandwidth (I work on DP3600) and i was surprised how well that reject ambient noise that are outside this spectrum. Agree sadly it's to small bandwidth to get good reproduction good thing after couple days You will get use to it and stop noticing. Would You recommend XT660d or something else in unlicensed dPMR segment?

they are discontinuing all analog radios... since when?

Did I not do that here? Doh!

Much harder but if you speak clearly, it’s fine after tuning your ear a bit. Of course, it beats analogue in fringe areas. I always felt it could be better.