3A-5

Stam Audio

Dynamics

Opto compressor - dual replica of LA-3A & LA-4 designs

Solid State Opto Compressor
The Stam Audio 3A-5 is a 1:1 replica of the two most popular solid state opto compressors in the world, the UREI LA-3A and the UREI LA-4. Using custom wound US made transformers, the absolute best T4B in the market by Kenetek Pro Audio in Kentucky and a British Carnhill output transformer, we can confidently say this is the only accurate sounding vintage LA-3A and LA-4 reproduction in the market at any price point.

Since both circuits shared the same transformers and we had a little space left inside we decided to go the extra mile and give you two compressors for the price of one including the revered LA-4 compressor in the same unit. This means you get the best electric guitar compressor and acoustic guitar compressor in history at the push of a switch.

Each 3A-5 is hand built at our lab in Chile one by one with the highest quality components available. No shortcuts have been taken to ensure you can use them interchangeably with an old LA-3A or LA-4. The 3A-5 now comes with a stereo link switch that allows you to use two of them in stereo.

Bringing back two classic compressors
The LA-3A quickly became the industry standard and most popular solid state optical compressor which has been used for over half a century in the best recording studios around the world. It’s unique coloration and character and its beautiful compression curve has made it the number one to go compressor for loud vocals and electric guitars. The LA-4, a Vactrol based optical compressor became famous for its transparency for acoustic instruments.

The best T4B in the market
Being the single most important part on a LA-2A and LA-3A and having tested every single T4B under the sun (including our own!!) we always come back to Bill Jone’s US hand-made T4B. It is simply identical to the original T4B from the 70’s U.S. Without this component there is no LA-3A.

Custom made transformers
Every 3A-5 comes with custom wound transformers made in the U.S. which are an exact replica of the originals. These transformers are built in small batches specifically for Stam Audio in the USA and have the same color, ratio and frequency response of the now extinct and unobtainable original B11147 input transformer.

Technical Specs
* LA-3A and LA-4 in one unit
* Kenetek US made T4B optical cell
* Custom US made input transformer
* Custom US made autoformer
* Carnhill output transformer
* True to the original LA-3A schematic
* Upgraded LA-4 Op-Amps
* Clearmountain MOD
* Stereo Lunk
* LA-4 switch
* Vintage VU Meter
* Less than 0.5% THD
* Vishay Capacitors
* Carbon resistors on audio path
* Hand made in Chile
* 2-year warranty
* 30-day money back guarantee