In April 2003 the G&L Custom Creations team decided to revisit the theme established by the ASAT Classic Three, using again a third, centrally located pickup and five position selector switch. This time, however, a reverse-wound S-500 middle pickup is installed in the middle position of an ASAT Classic. The basic idea for this kind of arrangement has been long established in the Nashville session player scene, where players often install a Strat® middle pickup in the middle position of a Telecaster® and swap the 3-position pickup selector with a 5-way unit.

The G&L Custom Creations Department dediced to build an instrument similar to the formula adopted by the Nashville guys but with a distinctly G&L flavor. In particular, that means a Semi-Hollow Swamp Ash body, ASAT Classic MFD pickups in place of Alnico Tele® pickups, and the S-500 MFD in place of the Strat pickup. The CCD team decided to ice the cake with a push/pull volume pot (changed to tone pot for run #2)that functions the same way as the S-500's mini-toggle switch, enabling additional pickup combinations of neck+bridge or all three pickups together.

The "S" designation comes from both internal designation for this instrument, due to its use of the S-500 middle pickup, and "Session" in homage to the origin of this guitar configuration.

ASAT Classic S build info:

January to March 2004 - first 100 piece production run completed
* 50 pcs. Honeyburst / Maple / Pearl pickguard
* 25 pcs. 3-Tone Sunburst / Maple / Tortoise Shell pickguard
* 25 pcs. 3-Tone Sunburst / Rosewood / Tortoise Shell pickguard

Late 2004 - 2005: one-offs occasionally; not formally available

April 19, 2007 – second 100 piece production run announced:

* 25 pcs. Butterscotch Blonde / Maple / 3-Ply Black pickguard
* 25 pcs. 3-Tone Sunburst / Rosewood / Tortoise Shell pickguard
* 25 pcs. Cherryburst / Maple / Pearl pickguard
* 25 pcs. Honeyburst / Maple / Pearl pickguard