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[Sonic Letterhead]                                                 EXHIBIT 10.15

                               November 24, 1997

                                                                    [Sonic Logo]
Mr. Orlando P. Rodrigues
375 Silverwood Circle
Southlake, TX 76092

Dear Orlando:

It is my great pleasure to offer you the position of Vice President of Marketing
for Sonix Technologies, Inc., reporting directly to the President & CEO.  Having
full responsibility for setting the marketing direction of the Company and for
executing it, you will also function as a senior member of the executive
management team and apply for a broad range of business skills to run the
enterprise.  Together, we will build Sonix Technologies into the most exciting,
customer-satisfying company in the history of hearing health care.

The terms of this offer include the following:

1.  Base salary will be $180,000 per year, paid twice-monthly.

2.  You will be paid a one time hiring bonus of $40,000 upon the beginning of
    your employment with Sonix.

3.  Benefits include vacation, holidays, medical insurance for the whole family
    (fully paid by Sonix), dental insurance and a 401k plan.

4.  At the first Board of Directors meeting after your acceptance of this offer,
    I will ask the Board to grant you an option to purchase 150,000 shares of
    common stock at the fair market price established by the Board on the date
    of grant. The grant will be subject to the standard terms and conditions of
    the Company's Stock Option Agreement. Your shares will vest over four years,
    the first 25% on the date of your first anniversary of employment at Sonix;
    the remainder in equal installments over the subsequent 36 month period.

5.  The Company will pay reasonable and customary relocation expenses for your
    move to the Salt Lake City area, including real estate commissions on both
    ends, moving of household goods, travel for your family, and temporary
    housing as appropriate. In addition, should you sell your home for less than
    you paid for it (plus improvements), Sonix will reimburse the difference to
    you, up to a maximum of $30,000.

6.  Employment at Sonix is not for a specific term and can be terminated by you
    or by the Company at any time, for any reason, with or without cause and
    with or without notice. If Sonix chooses to terminate your employment, there
    is no obligation to repay relocation costs
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    nor hiring bonus and, except for cause, Sonix will pay you six months salary
    as a severance package. If you choose to terminate your employment before
    completing one full year at Sonix, you agree to repay the hiring bonus and
    relocation costs.

7.  It shall be a condition of your employment that you execute the Company's
    standard non-disclosure agreement concerning confidentiality and
    intellectual property rights, and that you will not bring to Sonix any
    proprietary technology or information from any third party.

8.  Sonix anticipates your start date to be January 5, 1998. This offer of
    employment expires December 1, 1997. Please sign a copy of this letter,
    indicating your acceptance, and return it to me at your earliest
    convenience.

Orlando, you and I have an opportunity to help the hearing impaired as they have
never been helped before. The underlying technology of the Sonix DSP approach
has proven to be very effective in tests at the Mayo Clinic. While the science
is sound, the execution is a big challenge. Imagine the satisfaction we will
feel in 5 years, having built the best hearing aid company in the world and
having created the most satisfied customers in the history of the industry.
Please join me for the challenge and the fun!

Sincerely,

/s/ Andrew G. Raguskus

Andrew G. Raguskus
President and CEO

I accept the offer:    /s/ Orlando Rodrigues        Date:       12/1/97
                     -----------------------                 ------------

                                      -2-
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[Sonix Letterhead]

                                December 1, 1997

Mr. Orlando P. Rodrigues
375 Silverwood Circle
Southlake, TX 76092

Dear Orlando:

The Board of Directors, the management team and I are delighted that you have
accepted our offer to join Sonix as the Vice President of Marketing.  We look
forward to working with you to grow Sonix into a successful world class
organization.  This correspondence is an addendum to our offer letter dated
November 24, 1997.

The Company agrees that, in the event of an acquisition of greater than 50%
ownership by another industrial entity for the purposes of commercial
exploitation of Sonix technology during the option period, shares under the
option agreement indicated in our offer letter shall vest immediately.  This
accelerated vesting applies only to that portion of the original option
remaining at the time of acquisition.  If no such acquisition occurs as
indicated, you will be bound by the standard, four year vesting provision of the
Sonix Stock Option Agreement.

If you have any questions concerning this addition to your offer letter, please
contact me.  I look forward to seeing you and Chris at the Sonix Winter Party on
December 19th.  An invitation is enclosed.  Our team is excited to begin working
with you in early January.

Sincerely,

/s/ Andrew G. Raguskus

Andrew G. Raguskus
President and CEO

                                      -3-<PAGE>

[Sonic Letterhead]                                                 EXHIBIT 10.16

                               February 5, 1998

Mr. Michael D. Monahan
1063 Nelson Court
Pleasanton, CA 94566

Dear Mike:

It is my great pleasure to offer you the position of Vice President of Sales for
Sonix Technologies, Inc., reporting directly to the President & CEO. You will
have full responsibility for building and directing the sales force, for
developing a sales strategy and for executing it. Mike, you will also function
as a senior member of the executive management team and apply a broad range of
business skills to help me run the enterprise. Together, we will build Sonix
Technologies into the most exciting, customer-satisfying company in the history
of hearing health care.

The terms of this offer include the following:

1.  Base salary will be $140,000 per year, paid twice-monthly.

2.  You will be paid a one time hiring bonus of $20,000 upon the beginning of
    your employment with Sonix.

3.  Benefits include vacation, holidays, medical insurance for you and your
    dependents (fully paid by Sonix), dental insurance and a 401k plan.

4.  At the first Board of Directors meeting after you begin employment, I will
    ask the Board to grant you an option to purchase 110,000 shares of common
    stock at the fair market price established by the Board on the date of
    grant. The grant will be subject to the standard terms and conditions of the
    Company's Stock Option Agreement. Your shares will vest over four years, the
    first 25% on the date of your first anniversary of employment at Sonix; the
    remainder in equal installments over the subsequent 36 month period.

5.  In the event of an acquisition of greater than 50% ownership by another
    industrial entity for the purposes of commercial exploitation of the Sonix
    technology during the option period, shares described above shall vest
    immediately. This accelerated vesting applies only to that portion of the
    original option remaining at the time of acquisition. If no such acquisition
    occurs as indicated, you will be bound by the standard, four year vesting
    provision of the Sonix Stock Option Agreement.
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6.  The Company will pay reasonable and customary relocation expenses for your
    move to the Salt Lake City area, including real estate commissions on both
    ends, moving of household goods, travel, and temporary housing as
    appropriate.

7.  Employment at Sonix is not for a specific term and can be terminated by you
    or by the Company at any time, for any reason, with or without cause and
    with or without notice. If you choose to terminate your employment before
    completing one full year at Sonix, you agree to repay the hiring bonus and
    relocation costs.

8.  It shall be a condition of your employment that you execute the Company's
    standard non-disclosure agreement concerning confidentiality and
    intellectual property rights, and that you will not bring to Sonix any
    proprietary technology or information from any third party.

9.  Sonix anticipates your start date to be approximately March 2, 1998. This
    offer of employment expires February 13, 1998. Please sign a copy of this
    letter, indicating your acceptance, and return it to me at your earliest
    convenience.

Mike, you and I have an opportunity to help the hearing impaired as they have
never been helped before.  Imagine the satisfaction we will feel in 5 years,
having built the best hearing aid company in the world and having created the
most satisfied customers in the history of the industry.  Please join me for the
challenge and the fun!

Sincerely,

/s/ Andrew G. Raguskus/ by Debbie Thomas

Andrew G. Raguskus
President and CEO

I accept the offer:  /s/ Michael D. Monahan    Date:         2/8/98
                     ----------------------             ------------

                                      -2-<PAGE>

                                                                 Exhibit 10.17

                           [SONIX LETTERHEAD]

                               April 23, 1997

Dr. Gregory N. Koskowich
2635 Torrey Ct.
Pleasanton, CA  94588

Dear Greg:

It is my great pleasure to offer you the position of Vice President of
Engineering and Chief Technical Officer for Sonix Technologies, Inc., reporting
directly to the President & CEO.  Having full responsibility for setting the
technical direction of the Company and for executing it, you will also function
as a senior member of the executive management team and apply a broad range of
business skills to run the enterprise.  Together, we will build Sonix
Technologies into the most exciting, customer-satisfying company in the history
of hearing health care.

As we have discussed the terms of this offer include the following:

1.  Base salary will be $150,000 per year, paid twice-monthly.

2.  You will be paid a one time hiring bonus of $50,000, grossed up for taxes,
    upon the beginning of your employment with Sonix.

3.  Vacation, holiday and medical insurance will be provided according to our
    current benefits plan. Until we are able to obtain group coverage for all
    of our employees, Sonix will reimburse you for Cobra premiums.

4.  At the first Board of Directors meeting after your arrival, I will ask the
    Board to grant you an option to purchase 150,000 shares of common stock at
    the fair market price established by the Board on the date of grant
    (currently $0.14 per share). The grant will be subject to the standard
    terms and conditions of the Company's Stock Option Agreement. Your shares
    will vest over four years, the first 25% on the date of your first
    anniversary of employment at Sonix; the remainder in equal installments
    over the subsequent 36 month period.

5.  The Company will pay reasonable and customary relocation expenses for your
    move to the Salt Lake City area, including real estate commissions, not to
    exceed $60,000. The actual reimbursement will be grossed up for taxes.

6.  Employment at Sonix is not for a specific term and can be terminated by
    you or by the Company at any time, for any reason, with or without cause
    and with or without notice. If Sonix chooses to terminate your employment,
    there is no obligation to pay relocation costs

                                      -1-
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    nor hiring bonus and, in addition, Sonix will pay you six months salary as
    a severance package.

7.  It shall be a condition of your employment that you execute the Company's
    standard non-disclosure agreement concerning confidentiality and
    intellectual property rights, and that you will not bring to Sonix any
    proprietary technology or information from any third party.

8.  Sonix desires your start date to be as soon as possible, consistent with
    sufficient notice and a reasonable transition from your current
    obligations. This offer of employment expires May 4, 1997. Please sign a
    copy of this letter, indicating your acceptance, and return it to me at
    your earliest convenience.

Greg, you and I have an opportunity to help the hearing impaired as they have
never been helped before.  The underlying technology of the Sonix DSP approach
has proven to be very effective in tests at the Mayo Clinic.  While the science
is sound, the execution is a big challenge.  Imagine the satisfaction we will
feel in 5 years, having built the hottest high tech hearing aid company in the
world.  Please join me for the challenge and the fun!

Sincerely,

/s/ Andrew G. Raguskus

Andrew G. Raguskus
President and CEO

I accept the offer: /s/ Gregory N. Koskowich        Date:  May 4, 1997
                   ----------------------------          ---------------

                                      -2-

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