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                                                                  Exhibit 10.18


THIS SUBSCRIPTION AGREEMENT (the "Agreement") is made on the 13th day of
September 2000 between

1.   K/S HIMPP, a limited partnership under Danish law resident at Ny
     Vestergaardsvej 25, 3500 Vaerlose, Denmark (the "Partnership"); and

2.   SONIC INNOVATIONS, INC., 5330 South 900 East, Suite 240, Salt Lake City,
     Utah 84117-7261, USA (the "Limited Partner")

for the subscription for shares in the Partnership.

1.   DEFINITIONS

1.1. In this Agreement the following words and expressions shall have the
     following meanings unless where the context explicitly requires otherwise:

     "Shares"               means 10 A shares in the Partnership of a face value
                            of US$180,000.00 each or in the aggregate
                            US$1,800,000.00 of the Partnership's total
                            authorised and issued capital of US$16,350,000 after
                            the increase of the capital;

     "General Partner"      means the general partner of the Partnership; and

     "Articles"             means the Articles of Association of the Partnership
                            as adopted by the Partnership in its general meeting
                            on October 14, 1999.

2.   SUBSCRIPTION FOR SHARES

     The Limited Partner hereby subscribes for the Shares and the Partnership
     hereby accepts to be bound by the Limited Partner's subscription for the
     Shares.

3.   PAYMENT FOR THE SHARES

3.1  The total consideration of USD 1,800,000 for the subscription of the Shares
     in K/S HIMPP shall be paid to the Partnership no later than 8 days after
     the date of this Agreement.

4.   THE LIMITED PARTNER'S RIGHTS AND OBLIGATIONS

4.1. The Limited Partner hereby accepts and assumes all rights and obligations
     connected with the subscription for and holding of the Shares pursuant to
     the Articles or Danish law in general.

4.2. By his execution of this Agreement the Limited Partner covenants to have
     full knowledge of and to accept the terms and conditions of the Articles.

4.3. The Limited Partner hereby in particular covenants to have full knowledge
     of and to accept the following provisions of the Articles:

     (i)    The Partnership's general partner is HIMPP A/S whose liability is
            joint, direct and unlimited for all the Partnership's indebtedness
            and liabilities. The General Partner's issued and outstanding share
            capital is Danish Kroner, 1,800,000 after a capital increase in the
            amount of DKK 200,000 subscribed to by the Limited Partner. Each
            Limited Partner's liability for the Partnership's indebtedness and
            liabilities is personal, direct and pro rata and limited to the
            unpaid part (if any) of that Limited Partner's share in the
            Partnership's authorised and issued capital together with such
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            further contributions in cash as the Partnership acting in general
            meeting may resolve under Article 4.1., or as may be required to be
            contributed under Article 4.1.;

     (ii)   No Limited Partner shall have any rights of recourse against the
            General Partner for that Limited Partner's proportion of the
            Partnership's aggregate liabilities and indebtedness (Article 6.2.);

     (iii)  Upon the complete performance of each limited partner's obligations
            under his subscription agreement with the Partnership such limited
            partner is entitled to receive a certificate evidencing his shares
            (Article 7.1.);

     (iv)   The Shares and the certificates are non-negotiable instruments and
            shall be issued in the name of the owner (Article 7.2.);

     (v)    Each Share may be held by only one natural or legal person. No Share
            can be divided into sub-shares (Article 8.1.);

     (vi)   The shares may only be transferred to a transferee who is itself in
            control of or controlled by the transferor limited partner (Article
            8.2.).

     (vii)  If any Limited Partner shall become insolvent or be in breach of his
            duties and obligations towards the Partnership under the
            subscription agreement, the Articles or otherwise, the Partnership
            shall be entitled to request any loss realised thereby reimbursed by
            the relevant limited partner, and further to terminate without
            notice any patent license agreement entered into between the
            Partnership and the Limited Partner (Article 10); and

     (viii) The General Partner shall be charged with the administration of the
            Partnership and is entitled to remuneration for such work to the
            extent that such remuneration is reasonable when compared to the
            work and costs involved in the General Partner's performance of his
            duties. The General Partner may delegate administrative functions
            and tasks to third parties (Article 11.1.).

5.   LAW AND JURISDICTION

5.1. This Agreement shall be governed by and construed in accordance with Danish
     law.

5.2. Any dispute arising out of this Agreement or its interpretation shall be
     subject to the exclusive jurisdiction of the Maritime and Commercial Court
     in Copenhagen. This Clause shall not affect the construction of Article 17
     of the Articles, pursuant to which disputes concerning the interpretation
     of the Articles shall be settled finally by arbitration.

AS WITNESS the signatures of the parties hereto on the date first written above.


                                                           For the Partnership:
                                                            /s/Soren Westermann
                                             ----------------------------------

                                                           For and on behalf of
                                                                      K/S HIMPP

                                                       For the Limited Partner:

                                             ----------------------------------

                                                                /s/Jorgen Heide
                                             ----------------------------------
                                                           For and on behalf of
                                                        SONIC INNOVATIONS, INC.