MP1-L3 "The Big Daddy":
List Price: $875.00
Our Price: $650.00
(standard w/instrument DI)

MP1-L3 without DI.....
List Price: $800.00
Our Price: $600.00

Old School Audio MP1-L3 aka The "Big Daddy" microphone preamplifier and instrument DI for the industry standard API (TM) form factor. It utilizes 3 transformers, including the Lundahl massive LL7903. The MP1-L3 is the latest addition to the OSA family, and like its nick name there is nothing small about it. This pre-amp gives your low end a place to call home. The midrange is like no other, and the top end is tight and crisp.

MP1-C "The Vintage":
List Price: $660.00
Our Price: $500.00
(standard line level on the 1/4" input)

Also can be ordered with DI.
MP1-C with DI.....
List Price: $735.00
Our Price: $550.00

The MP1-C is OSA's "Vintage" model. Faithful to the design practices of the golden age of audio, OSA was able to design an input transformer that captures the fatness and solidity of early designs. This preamp is the one to add girth to your guitars and drums, while preserving the rich, 3 dimensional detail of the upper mids and highs. The MP1-C will bring you back to the glory days of rock n' roll, it's got color and crunch galore.

Old School Audio introduces the MP1-A, a low noise, high gain, transformer in and out microphone preamplifier for the industry standard API (TM) form factor.

The MP1-A was OSA's first product offering. Based on a custom split primary input transformer, we experimented with different winding styles and core material until the sound was tailored into a palette that is pleasingly three dimensional to the ears, and effortless to work with. Clear and open in the top end, rich and liquid in the midrange, and full and deep in the bottom end characterize this model.

The MP1-L is popularly known at OSA as the "Mutant". Based on the incredible Lundahl 1538XL input transformer, this mic pre will rock your world. Lundahl is the one company who has advanced the field of transformer design into the new millennium. The spine rattling bottom end is huge, round, and full. the midrange is so present that you will swear that it can’t be solid state, and the top is elegant and silky.

The Power Rack

Shown above with no modules installed

The Track Pack

Shown above with 8 OSA modules installed
(modules must be purchased seperately)

Our Price: $675.00 NOTE that OSA racks are no longer sold seperately.

The Track Pack is completely backwards/forwards Pin Compatible with the API tm 500 series mic pre lunchbox designed format.
Note: this price is for the rack only and does not contain modules.
The TrkPak holds 8 OSA modules and $675 price is for power supply & rack only