<PAGE>

                                                                    Exhibit 4.06

                                SECOND AMENDMENT
                                ----------------

          SECOND AMENDMENT (this "Amendment"), dated as of May 14, 2001, among
NEXTMEDIA GROUP, INC., a Delaware corporation ("Holdings"), NEXTMEDIA OPERATING,
INC., a Delaware corporation (the "Borrower"), the lenders from time to time
party to the Credit Agreement referred to below (the "Lenders"), and Bankers
Trust Company, as administrative agent (the "Administrative Agent"). All
capitalized terms used herein and not otherwise defined herein shall have the
respective meanings provided such terms in the Credit Agreement referred to
below.

                              W I T N E S S E T H:
                              - - - - - - - - - -

          WHEREAS, Holdings, the Borrower, the Administrative Agent and the
Lenders are parties to a Credit Agreement, dated as of July 31, 2000 (as
amended, modified or supplemented through, but not including, the date hereof,
the "Credit Agreement); and

          WHEREAS, Holdings and the Borrower have requested, and the Lenders
have agreed to, the amendments to the Credit Agreement as provided herein;

          NOW, THEREFORE, it is agreed:

          1. Section 9.09(a) of the Credit Agreement is hereby amended by
deleting the columns appearing therein in their entirety and inserting the
following new columns in lieu thereof:

             "Period                                       Ratio
              ------                                       -----

Effective Date through and including
  March 30, 2001                                         7.00:1.00

March 31, 2001 through and including
  June 29, 2001                                          6.75:1.00

June 30, 2001 through and including
  September 29, 2001                                     6.50:1.00
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              Period                                       Ratio
              ------                                       -----

September 30, 2001 through and including
  December 30, 2001                                      6.25:1.00

December 31, 2001 through and including
  March 30, 2002                                         6.00:1.00

March 31, 2002 through and including
  June 29, 2002                                          5.50:1.00

June 30, 2002 through and including
  September 29, 2002                                     5.25:1.00

September 30, 2002 through and including
  December 30, 2002                                      5.00:1.00

December 31, 2002 through and including
  March 30, 2003                                         4.50:1.00

March 31, 2003 through and including
  June 29, 2003                                          4.25:1.00

June 30, 2003 through and including
  September 29, 2003                                     4.00:1.00

September 30, 2003 through and including
  March 30, 2004                                         3.75:1.00

March 31, 2004 and thereafter                            3.50:1.00".

          2. Each of Holdings and the Borrower hereby represents and warrants
that both before and after giving effect to this Amendment (x) no Default or
Event of Default exists on the Second Amendment Effective Date (as defined
below) and (y) all of the representations and warranties contained in the Credit
Agreement and in the other Credit Documents shall be true and correct in all
material respects on the Second Amendment Effective Date with the same effect as
though such representations and warranties had been made on and as of such date
(it being understood that any representation or warranty made as of a specific
date shall be true and correct in all material respects as of such specific
date).

          3. This Amendment is limited as specified and shall not constitute a
modification, acceptance or waiver of any other provision of the Credit
Agreement or any other Credit Document.

          4. This Amendment may be executed in any number of counterparts and by
the different parties hereto on separate counterparts, each of which
counterparts when executed and delivered shall be an original, but all of which
shall together constitute one and the same
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instrument. A complete set of counterparts shall be lodged with the Borrower and
the Administrative Agent.

          5. THIS AMENDMENT AND THE RIGHTS AND OBLIGATIONS OF THE PARTIES
HEREUNDER SHALL BE CONSTRUED IN ACCORDANCE WITH AND GOVERNED BY THE LAW OF THE
STATE OF NEW YORK.

          6. This Amendment shall become effective on the date (the "Second
Amendment Effective Date") when each of Holdings, the Borrower and the Required
Lenders shall have signed a copy hereof (whether the same or different copies)
and, in each case, shall have delivered (including by way of telecopier) the
same to the Administrative Agent at the Notice Office.

                                      * * *
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          IN WITNESS WHEREOF, each of the parties hereto has caused a
counterpart of this Amendment to be duly executed and delivered as of the date
first above written.

                                              NEXTMEDIA GROUP, INC.


                                              By________________________________
                                                Name:
                                                Title:

                                              NEXTMEDIA OPERATING, INC.


                                              By________________________________
                                                Name:
                                                Title:

                                              BANKERS TRUST COMPANY


                                              By________________________________
                                                Name:
                                                Title:

                                              LEHMAN COMMERCIAL PAPER INC.


                                              By________________________________
                                                Name:
                                                Title:
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                                              CREDIT SUISSE FIRST BOSTON


                                              By________________________________
                                                Name:
                                                Title:

                                              CITICORP USA, INC.


                                              By________________________________
                                                Name:
                                                Title:

                                              UNION BANK OF CALIFORNIA, N.A.


                                              By________________________________
                                                Name:
                                                Title: