The amps are known for their characteristically clean tone.
The Twin has seen a number of revisions since its introduction, both internal and external, with its designs sometimes varying greatly from one year to the next.
Teletronix later became a division of Babcock Electronics Corp. In 1967 Babcock's broadcast division was acquired by Bill Putnam's company, Studio Electronics Corporation, shortly before he changed the company’s name to UREI.
Three different versions were produced under the auspices of these different companies before production was discontinued around 1969-70.
Many believe they were lay-out reference lines that were never intended to make it into production; that makes sense since they only appeared for about the first 4-6 months.
of North Hollywood This iteration had an added a compress/limit switch on the back Input transformer changed to UTC A-10 Limit/Compress switch on the back This revision starts with unit #384In the late 70's, UREI brought back the LA-2A for a run of around 200 units Return of the greyface front panel The T4A is replaced with a T4B A safety switch is added so power shuts off when front panel is opened Four titans of engineering and production — Joe Chiccarelli, Jacquire King, Joel Hamilton & Trevor Lawrence, Jr.
— explain why committing to sounds during tracking is an essential part of their Platinum-approved workflow, and how UAD Unison mic preamp technology figures into it.
In addition to these iterations of the LA-2A, two “re-issues” were put out, one while still under UREI, and one under UREI after being purchased by Harman/JBL.
Faceplate is painted grey First compressor to use of photo resistors and luminescent panels to achieve gain reduction - the T4A Produced by Teletronix in Pasadena, CA (sometimes labeled Los Angeles, sometimes labeled Sunnyvale) Octal jumper socket located before the UTC HA-100X input transformer for pad/pre-emphasis modules Later units included a variable pre-emphasis filter, R37 All rear panel graphics are hand stenciled or stamped Some units offer a fixed Limit function while others feature a Limit/Compress switch on the back Faceplate is brushed aluminum Teletronix patent acquired by Putnam's Studio Electronics Corp.