<PAGE>   1
Rockford Corporation Debenture Ownership
As of December 31, 1998
<TABLE>
<CAPTION>
                                                                                                                    Number of Shares
Group                                  Debenture Holder                                           Amount               On Conversion
------------------------------------------------------------------------------------------------------------------------------------
<S>                                    <C>                                                    <C>                   <C>
8.5% Debentures:

Bartol Family                          Carrio Cabling Corporation                               $500,000                     204,762

                                       Nicholas G. Bartol                                      $7,507.50                       3,075

                                       Timothy C. Bartol                                       $7,507.50                       3,075

                                       Ann Farr Bartol                                         $7,507.50                       3,075

                                       Pamela B. Carrio                                        $7,507.50                       3,075

                                       Mary Brigham Paul                                       $7,507.50                       3,075

                                       Rebecca Paul Harris                                     $7,507.50                       3,075

                                       Timothy C. Bartol                                      $20,000.00                       8,192

                                       Nick G. Bartol                                         $39,000.00                      15,970

                                       Renee F. Bartol                                        $10,000.00                       4,094

Gary Suttle and 3G                     The J. Goldress Trust,                                 $20,000.00                       8,192
                                           Jerry  E. Goldress, Trustee

                                       Suttle Brothers Investments LLC                        $21,000.00                       8,600

                                       Suttle Brothers Investments LLC                        $31,500.00                      12,900
</TABLE>

<PAGE>   2

Rockford Corporation Debenture Ownership
As of December 31, 1998
<TABLE>
<CAPTION>
                                                                                                                    Number of Shares
Group                                  Debenture Holder                                           Amount               On Conversion
------------------------------------------------------------------------------------------------------------------------------------
<S>                                    <C>                                                    <C>                   <C>


                                       Lee Katz                                                $1,406.25                         576

                                       Richard J. Puricelli                                    $1,406.25                         576

                                       Carole O'Connor                                         $1,406.25                         576

                                       Richard D. Saunders                                     $1,406.25                         576

                                       Craig D. Crisman                                        $1,406.25                         576

                                       Marvin A. Davis                                         $1,406.25                         576

                                       Brian R. Stone                                          $1,406.25                         576

                                       Martin M. Batt                                          $1,406.25                         576

Rockford Employees                     Ronald N. Trout &                                       $4,922.00                       2,017
                                           Jonie Schuster Trout, Community Property

                                       The Principal Financial Group                          $10,000.00                       4,094
                                           (401K) Ronald N. Trout, Owner

                                       The Principal Financial Group                          $15,755.00                       6,450
                                           (401K) Alan R. Zimmerman, Owner

                                       Christopher D. Barnes                                   $2,817.00                       1,152

                                       The Principal Financial Group                           $3,521.00                       1,441
                                           (401K) Gary E. Church, Owner

                                       The Principal Financial Group                             $704.00                         288
                                           (401K) Thomas D Coulson, Owner
</TABLE>

<PAGE>   3

Rockford Corporation Debenture Ownership
As of December 31, 1998
<TABLE>
<CAPTION>
                                                                                                                    Number of Shares
Group                                  Debenture Holder                                           Amount               On Conversion
------------------------------------------------------------------------------------------------------------------------------------
<S>                                    <C>                                                    <C>                   <C>

                                       The Principal Financial Group                           $3,521.00                       1,441
                                           (401K) Herb Kane, Owner

                                       The Principal Financial Group                           $3,521.00                       1,441
                                           (401K) William E. Turner, Jr., Owner

                                       The Principal Financial Group                          $11,056.00                       4,528
                                           (401K) Angie Gitch, Owner

                                       The Principal Financial Group                           $5,000.00                       2,047
                                           (401K) H. Christopher Parvin, Owner

                                       Wayne Harris                                           $60,500.00                      24,777

                                       The Principal Financial Group                          $39,500.00                      16,177
                                           (401K) Wayne Harris, Owner

                                       The Principal Financial Group                           $1,789.15                         731
                                           (401K) Donald D. Hammerle, Owner

                                       Christine Trapp                                           $704.00                         288

                                       The Principal Financial Group                             $704.00                         288
                                           (401K) Margie Williams, Owner

                                       The Principal Financial Group                           $1,760.00                         722
                                           (401K) Richard H. Gentry, Owner

                                       The Principal Financial Group                           $2,112.00                         864
                                           (401K)  Mark Lowe, Owner

                                       The Principal Financial Group                           $1,300.00                         533
                                        (401K) Mark F. Rudolph, Owner
</TABLE>

<PAGE>   4

Rockford Corporation Debenture Ownership
As of December 31, 1998
<TABLE>
<CAPTION>
                                                                                                                    Number of Shares
Group                                  Debenture Holder                                           Amount               On Conversion
------------------------------------------------------------------------------------------------------------------------------------
<S>                                    <C>                                                    <C>                   <C>

                                       Matthew Clonts                                          $1,760.00                         722

                                       The Principal Financial Group                           $5,000.00                       2,047
                                           (401K) Leslie K. Ferris, Owner

                                       Mark Albers                                             $1,760.00                         722

                                       The Principal Financial Group                           $3,520.00                       1,441
                                           (401K) Mark Albers, Owner

                                       The Principal Financial Group                          $50,000.00                      20,477
                                           IRA - James M. Thomson

                                       The Principal Financial Group                           $7,042.00                       2,885
                                           (401K) - David Boshes, Owner

                                       The Principal Financial Group                          $13,000.00                       5,323
                                           IRA  - David Boshes, Owner

                                       The Principal Financial Group                             $114.00                          47
                                           (401K) Victoria L. Hodson, Owner

                                       The Principal Financial Group                           $4,250.39                       1,742
                                           (401K) David Richards, Owner

Others                                 Var & Co.,                                             $23,606.00                       9,666
                                        First Trust National Association

                                       Graham Humes                                            $1,225.00                         503

                                       Gordon A. Jr. & Blair B. MacInnes                       $1,531.00                         628

                                       John P. Lloyd &                                         $5,000.00                       2,047
                                            Beverly A Lloyd, Joint Tenants
</TABLE>

<PAGE>   5

Rockford Corporation Debenture Ownership
As of December 31, 1998
<TABLE>
<CAPTION>
                                                                                                                    Number of Shares
Group                                  Debenture Holder                                           Amount               On Conversion
------------------------------------------------------------------------------------------------------------------------------------
<S>                                    <C>                                                    <C>                   <C>

                                       John P. Lloyd &                                        $10,000.00                       4,094
                                           John M. Lloyd, Joint Tenants
</TABLE>