I'm not sure what Tom was saying, but he has considerable expertise in this
field.
Before you give up on the TS-590, I would try some things you may already
have thought of:
You may be having to turn the output of your headphone jack down so far, in
order not to over-drive the input to your hearing aid, that the signal is
mixed with a lot of broadband noise. Some attenuation in the right place
might improve things.
The menu system of that rig includes an equalizer. Perhaps you could improve
the sound by making some adjustments. I have not had to use cochlear
implants, but the last information I had was that you experienced all sounds
at higher-than-normal pitch, and the sounds were a lot more like tones than
natural sounds coming through intact auditory nerves. So I'm not sure how
the "analog sound" from ham radio would be much different from what you are
getting from your digital rig, unless something is being driven into
distortion.
I don't own a TS-590. Some folks in the past have complained about the
digital sound of some ham receivers (they didn't have severe hearing loss, I
think). My FT-950 uses DSP for IF filtering and SSB/CW/AM detection, and the
audio circuit after the D/A converter deliberately rolls off the highs,
starting at 1 KHz, with a gentle roll-off of 6 dB per octave, probably to
diminish some of this harshness.
VoIP systems for telephony run at different bitrates, depending on economics
and infrastructure. The good ones will perform about as well as the 64 kBps
mu-law digital signals we have had over long-distance for several decades.
The poor VoIP implementations sacrifice some naturalness, and make the
talker at the other end sound somewhat like an early speech synthesizer. The
same goes for cell phones and the low-bitrate codecs being promoted for ham
radio purposes.
The encoding system we use for NLS talking books, adaptive multirate
wideband extended, is, at its base mode, the same codec used in GSM cell
phones like those used on AT&T and T-Mobile. But if you give it enough bits
and add high-frequency extensions to the base code, speech can sound really
natural at a bitrate of only 24 k bits per second.
More audio coding discussion some other time; it's time that I went to bed.
73,
Lloyd Rasmussen, W3IUU, Kensington, MD
http://lras.home.sprynet.com
-----Original Message-----
From: Mike Keithley
Sent: Saturday, January 28, 2017 10:18 PM
To: [log in to unmask]
Subject: Re: Analog sound?
Very sorry but I don't understand this. As far as I know, the output at the
earphone jack is analog, not digital.
----- Original Message -----
From: Tom Brennan <[log in to unmask]>
To: [log in to unmask]
Date: Thursday, January 26, 2017 6:50 am
Subject: Re: Analog sound?
>
>
> Mike, you might try a d/a converter on the earphone output of your 590
> into
> another speaker. Might get rid of the problem. I've had clients with
> mixed
> results from going digital/analog but could be worth a shot.
>
> Tom
>
>
> Tom Brennan KD5VIJ, CCC-A/SLP
> web page http://titan.sfasu.edu/~g_brennantg/sonicpage.html
>
> On Tue, 24 Jan 2017, Mike Keithley wrote:
>
> > Date: Tue, 24 Jan 2017 19:48:23 -0800
> > From: Mike Keithley <[log in to unmask]>
> > Reply-To: For blind ham radio operators <[log in to unmask]>
> > To: [log in to unmask]
> > Subject: Analog sound?
> >
> > Hello list,
> >
> > This might sound strange, but I'm getting discouraged with the sound
> > from my ST590. It's just a digital sound, and my cochlear implants
> > (being digital devices themselves) just don't handle digitally-generated
> > sound well. I'm seriously thinking of finding an old ham receiver with
> > analog signal processing and putting up with poor selectivity etc.
> >
> > For example, my iPhone sounds digital, even with a good connection. To a
> > lesser extent, my land line phone, which is actually VOIP through
> > Comcast, also sounds digital. But the digital effect disappears when
> > using my wife's wired landline phone (which I'm sure turns into VOIP
> > along the network).
> >
> > now the TS590 just sounds digital even with the noise limiter and
> > blanker turned off and listening to AM broadcast stations with broadest
> > selectivity. But my Victor Stream (which is actually digital), sounds
> > more analog and better. In the 590, I can turn the RF gain down to keep
> > an SSB signal from influencing the AGC, and this removes the digital
> > effect somewhat. But I think something got lost in the audio quality
> > (for my ears at least) of modern transceivers. Maybe I'll try building
> > my own receiver, like the regenerative receiver I built in my novice
> > days. That used vacuum tubes and was inspired from an article in the
> > BTP. It wasn't much, but it was analog!
> >
> > Sorry for the rant. I used to enjoy phone, but it now sounds so gross
> > sometimes that I spend more time on CW and deal with weird
> > digitally-generated effects, which can get rather wild with sharp
> > selectivity.
> >
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