Thread Subject: Re: More questions/discussion on gain

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From: John Combs (jcombs)
Date: Mon, Nov 13 2006 12:20 PM

Michael,

Nice to meet you online.

One thing you mention in your text below -- an audio amplifier which
claims to have 60 dB of gain. This is another thing we should address
in the TEITAC discussions, lack of a testing standard for measuring true
amplifier gain. Many manufacturers claims very high gain numbers, but
don't deliver anything close to what they say.

Let's consider 60 dB of audio gain. If the initial maximum audio level
on an analog phone receiver is 1 Watt of sound power, a 60 dB boost of
this gives us 1 million Watts!

Regardless of claims, I've never found an inline handset amplifier that
actually exceeded 30 dB of true gain.


- John Combs


-----Original Message-----
From: = EMAIL ADDRESS REMOVED =
[mailto: = EMAIL ADDRESS REMOVED = ] On Behalf Of Michael
Byington
Sent: Monday, November 13, 2006 12:40 AM
To: = EMAIL ADDRESS REMOVED =
Subject: Re: [teitac-telecom] More questions/discussion on gain

Diane, John, Jim, and others

I am new to this list, and like John, I want to introduce myself and
tell a little bit about my background. I was asked to participate on
this list by the President of the Council of Citizens with Low Vision
International (CCLVI) , Bernice Candarian. I am a past President of
CCLVI. I am legally blind and am a heavy user of visual aids for
information access although i also quite often choose to use screen
readers as well.

In terms of my professional background, I have a Master's in
Communications, and I have worked for many years, in a combination of
human service, disability rights advocacy, and telecommunications access
positions. I served as Section 504 Coordinator for the City of Wichita
just after graduating from college, and long before the ADA. I have
worked for two centers for independent living in direct service and
administrative positions, have served as the Technical Consultant for
the Kansas Affiliate Program to the Helen Keller National Center for
Deafblind Youths and Adults, and have worked as a professional lobbyist
representing several human service interests. For two and a half years,
I served as Contract Administrator for Telecommunications Relay Services
for the State of Kansas, and also as a part of that job, I had overall
responsibility for our telecommunications equipment distribution program
in Kansas. I left that position three years ago and returned to direct
service; I currently serve as a Shift Manager in a residential training
facility for people who are newly blind or visually impaired. In my
current position, I do quite a bit of teaching and independent living
training with people who are sensory impaired, but who are not at the
expert or even semi-skilled level of competence when it comes to the use
of telecommunications accommodations such as screenreaders, enlarging
software, etc.

I do not begin to have the technical background that John does, and I
thank him for his insightful posting. What I want to share, however, are
some practical thoughts as to what may work for the broad plethora of
people with sensory disabilities who need telecommunications
accommodations on the job, and what needs to be fleshed out in the
regulatory process for 508 and 255. I am going to address more of 508.
With regard to 255, I never have been fond of the "readily achievable"
level of compliance and enforcement built into the statute, and I will
leave the line of demarcation as to what is readily achievable to build
in as opposed to make compatible for add-on to those with engineering
skills superior to mine, and to those who have more experience with
telecommunications and "readily achievable" based case law.

The central issue being discussed in the postings I have read on this
list and its parent website, however, relate to what standards of
universal design may be required by regulation to accommodate all of
those with disabilities who may need accommodation in the 508 covered
workplace. The first thing I want to caution is that universal design in
developing parameters for telecommunications access for sensory impaired
is a much less exacting science than it is to place physical standards
for the built environment in an operational document such as the ADAAG.
It is easier, and less personalized or individualized to determine the
minimum requirements for width, slope, height of truncated domes, etc.,
than it is to determine how much gain, or what font size or
screenreading hierarchy will work best for individual users in order for
them to work competitively and efficiently.

I am not going to mention specific brands of equipment because I have
been our of the telecommunications equipment distribution day to day
operations for nearly three years now, so I know that brands, models,
and company alliances have all changed, and I have not really kept up. I
will say, however, that when giving out amplified telephone equipment in
Kansas, our program would not fund equipment with less than about 25 db
of amplification, and some thpes of amplification equipment we funded
had a gain of up to 60 db. This kind of technology could not be built in
to a telephone system as a feature of universal design. One of many
reasons is that the level of very high amplification needed by some
severely hearing impaired individuals could actually be injurous to the
hearing of a normally hearing individual, or individual with a less
severe loss. Yet, I would contend that the worker who has a very severe
impairment, requiring, for example, 55 db of gain, should still have the
option to choose to use their hearing for telephone communication rather
that a traditional TTY, Cap-Tel, or other text based technology.

The same is true for accommodations for people who are blind and
visually impaired. Certainly a certain degree of enlargement
capabilities, and speech access can be built into a universal system,
but for the professional, well-trained user of such software as JAWS,
Window Eyes, or Zoomtext, the features of these particular pieces of
software configured specifically for the individual user, can make the
difference as to whether the person can work at a competitive level of
quality and productivity.

Thus, while I think a certain amount of the required minimum standards
to be built into systems as universal design features are important for
overall, universal accessibility, most people who have significant
degrees of sensory disabilities are going to need more powerful and
personalized solutions. The ability to add on, and compatibility with,
individualized modifications therefore remains paramount.

It is becoming increasingly possible to in fact make access features
portable so that the worker moving from system to system or place to
place may have full access even if all access features are not built
into each system, terminal, or other linked equipment. For example, two
very functional brands of screenreaders can now be loaded onto any
system without going through installation procedures, and through simply
plugging a jump drive into a USB port. I think regulatory changes have
to be firm in providing for such needed individualized accommodations,
but I also think we make a regulatory mistake if we promulgate
regulatory language that relies on the state of current science. There
is every reason to believe that the progression of assistive technology
is moving more and more toward situations where personally customized
access for people with specific and severe disabilities will be provided
universally through personally carried add on devices attached to
systems in-line, through USB ports, and in other evolving ways.

I hope this is helpful. I look forwarding to hearing from many of you on
the call later today.

Michael Byington


>>> "Diane Golden" < = EMAIL ADDRESS REMOVED = > 11/12/2006 5:18 PM >>>
First -- thank you, thank you, thank you, John for the info you
provided. I really needed much of that years ago when we began
procurement reviews, but it is still extremely helpful now (smile.)

So in reference to the issue of gain or volume control it appears all
phones have about 12 dB of gain/volume control built into the product to
conform to HAC 68.317. However, the current 508 requirement,
1194.23(f), for 20 dB is not being met as a built-in feature which was
the intent of the standard.
(I can say this is accurate from the procurements I'm familiar with at a
state level, but would be interesting to see if it is an accurate
reflection of what federal procurement officials are seeing also.)

So to follow up on Jim's questions, it would seem not a problem to
continue to require the 12 dB gain as a baseline for built-in gain
(provided there was a better definition of how gain is measured to
ensure consistency.) But clearly this will do nothing to increase
accessibility -- in fact it will appear to be a lessening of the current
508 standard since that standard has not been met as intended.

When you described the distortion and shift to amplifying the high
frequencies for gain significantly over 12 dB, were you talking about
just "add-on" amplifiers to a base phone product (e.g. in-line
amplifiers or substituted handsets) or were you also talking about stand
alone amplified phones? I would think this would influence Jim's second
option for a standard that requires more than 12 dB of gain but allows
that to be "high frequency amplification". Specifically, how much of
that "shifted"
gain
could/should be delivered as a built-in feature to every phone
purchased?

And last, maybe it is just our experience in Missouri, but we find very
few folks who go to "add-on" AT with reference to telephone access. In
fact over the years, in-line amplifiers and other add-on AT products
have really faded from the market. Almost everything now is a
substituted product assumedly because of all the factors John described,
power issues, frequency shifting, default override options, etc. Or
folks go to hearing aid coupling (more direct boot connections, cochlear
links, etc.) So I'm not sure how helpful it would be to add a telecom
standard that requires compatibility with add-on products when there are
so few such AT products on the market any more.

Diane

Diane Cordry Golden, Ph.D.
National Association of State Chief Information Officers Missouri
Assistive Technology Office

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