My $00.02. Been a ham op for 46 plus years. High speed CW will ALWAYS be my first love, and weak CW in the noise with QRM and QSB.
That said, D-Star is what it is for reasons other than fidelity. Others have touched upon it: narrow bandwidth, ecoms, integrated text/date, etc., Frankly, my Echolink through my 220 repeater produces audio and reliability superior to D-Star. So what? I can't route by callsign, and I'm not contributing to the state-of-the-art by using it. Will I give up Echolink? No. Will I give up D-Star? Depends. And I will NEVER give up CW. But right now, as a new technology D-STar floats my boat and I want to be a part of it. It only will get better until something better than that comes along. I heard the same criticisms said about SSB. But SSB gave us 1.5 Khz reliable voice transmission and is today the main stay. As they say, if its not your cup of tea, don't sip. 73, Jozef WB2MIC On 9/1/2010 18 19 Hours, n2gyn wrote: > > It's NOT a microphone issue. It's the small bit processing. I have > been in Pro sound for most of my life. Their is NO WAY to get any > quality at 8bit. This is unexceptionable to me! I rather listen to all > the QRM and QRN in the world with analog. > I am very surprise that their are not more people that feel this way. > The bit rate has to be at lest 28bit to starting sounding acceptable. > John > ======================================== > > --- In [email protected] > <mailto:dstar_digital%40yahoogroups.com>, "Ted Wrobel" <twro...@...> > wrote: > > > > There are likely two possible areas for improvement and one where > > improvement is likely impossible. > > > > Some radios seem to have better transmit audio than others. Many > people find > > the IC-2200 very good while many people find the ID-880 very bad. > > Possible the receive audio could also be improved by some additional > audio > > processing. > > > > Much of the "poor" quality in DStar can be attributed to the AMBE > Vocoder. > > This is a very complex algorythm that converts a high bit-rate voice > data > > stream into a very low bit-rate data stream. By its very nature this > is a > > lossy process. Removing bits must reduce the information content of the > > data. AMBE attempts to maximize the bit-rate while maintaining > 'acceptable' > > audio quality. Some people may find the resulting sound > unacceptable. Much > > like the battles over vinyl vd CD vs MP3 and tubes vs solid state in the > > music world, some ears are very sensitive to the aural content while > others > > are quite insensitive. > > > > In a search to find a better sound for my 880, I contacted Bob, > AB5N, who > > sells upgrades to a vatiety on ham microphones hoping he could provide a > > solution. below is his response. I hope it helps explain the problem. > > > > 73, > > Ted > > > > W1GRI > > > > Ted- > > > > We have a conundrum here. Most people buy the ID-880H to use it on > D-Star. > > > > Otherwise they would just buy a less-expensive rig. > > > > D-Star is a extremely compressed digital voice mode. They don't want to > > digitize any audio that isn't > > directly responsible for intelligibility. That passband is > 300-3000... the > > old telephone response. > > Any audio that is outside that range would just be "wasting bits" > encoding > > sound that does not > > help you understand what is being said. So, the mic audio is tailored > > narrowly to that passband > > for D-Star in the radio. Problem is, on FM, it sounds light at the > bottom. > > If it was me, I would have had separate mic EQ circuits switched in > for each > > mode. > > > > Thus, if we change the mic response curve to un-do what the mic > pre-amp EQ's > > are doing, D-Star will go down the drain. Digital distortion is > horrible. > > I've tried this experiment with my ID-800. > > I had to remove the new element and go stock again. > > > > As well, Icom engineers have always felt that their radios should have > > "communications-grade audio". None of their FM radios sound as > pleasing as > > say a Yaesu FM mobile (totally analog radios). When you go to an > Icom like a > > IC-7000, it is like comparing a vinyl record with a MP3. > > > > So, for radios that use the 133 or 131 - which do not have D-Star, > indeed my > > mic element gives a very nice improvement. > > > > Uh oh... major storm here...tornado warnings.. I better unplug the > router > > and laptop. > > > > Hope that clears it up... I wish I could help! > > > > Bob-AB5N > > > > > > > > _____ > > > > From: [email protected] > <mailto:dstar_digital%40yahoogroups.com> > [mailto:[email protected] > <mailto:dstar_digital%40yahoogroups.com>] > > On Behalf Of n2gyn > > Sent: Wednesday, September 01, 2010 14:27 > > To: [email protected] > <mailto:dstar_digital%40yahoogroups.com> > > Subject: [DSTAR_DIGITAL] Re: Bit Rate? > > > > > > > > > > Thank you all for you reply and comments. > > Let me make myself clearer. > > I would like to see the audio quality of D-Star be improved. To MY ears' > > everyone sound like a robot. I thought this was due to the low bit > rate. I > > am NOT impressed with the digital voice mode. I want to hear a more > natural > > sounding voice. My telephone sounds better. > > How could this be achieved if not by bit rate? > > John > > ==================================================== > > > > --- In [email protected] > <mailto:dstar_digital%40yahoogroups.com> > > <mailto:dstar_digital%40yahoogroups.com> , "Ted Wrobel" <twrobel@> > wrote: > > > > > > Hi John, > > > > > > Not quite sure what you are thinking, but here is a brief overview > of the > > > DStar data stream. > > > > > > The input to / output from the data processing 'module' of the > radio is a > > > 9600 Baud stream - which equates to roughly 960 eight bit > characters per > > > second. > > > > > > The logic of the system digitizes the voice in and passes it to > the AMBE > > > Vocoder that compresses the data stream - a lot. > > > > > > It is the compresion by the Vocoder that is both the strength and > weakness > > > of DStar. The compression makes a low data rate (and thus low > bandwidth) > > > possible, but it also means that the re-constituted voice is an > > > approximation of the voice input. Generally the reconstructed voice is > > > pretty good, and given the bandwidth it is really quite remarkable. > > > > > > In any case, the baud rate of the system is fixed and cannot be > modified > > at > > > any stage of the process without making the resulting stream > > unrecognizable > > > to other DStar systems. > > > > > > Note that the data rate over the internet can be much higher, but the > > chain > > > from repeater controller to / from the radio is fixed for DV comms at > > 9600. > > > > > > > > > 73 > > > Ted > > > W1GRI > > > > > > _____ > > > > > > From: [email protected] > <mailto:dstar_digital%40yahoogroups.com> > > <mailto:dstar_digital%40yahoogroups.com> > > [mailto:[email protected] > <mailto:dstar_digital%40yahoogroups.com> > > <mailto:dstar_digital%40yahoogroups.com> ] > > > On Behalf Of n2gyn > > > Sent: Tuesday, August 31, 2010 16:54 > > > To: [email protected] > <mailto:dstar_digital%40yahoogroups.com> > <mailto:dstar_digital%40yahoogroups.com> > > > > > Subject: [DSTAR_DIGITAL] Bit Rate? > > > > > > > > > > > > > > > Most radios are sent to 8bit. Can all radio's bit rate be changed? > > > I believe it is the LOW bit rate that lowers the quality of d-star's > > audio. > > > Is there a sub menu in the radio's. Also can the repeater's rate > be change > > > to a higher rate? > > > John > > > > > > >
<<attachment: jozef.vcf>>
