Jessica Williams take on Paul C. Buff, Valley People, and the Trans Amp #LZ. Big thanks to the folks over at Lumafield for scanning two amps for me! Go check the full scans out here. The larger one is the Trans Amp and the smaller is an unknown amp. Check out different views in the Bookmarks and adjust the layers. It's very magical looking and super informative! Kit
Valley People began when Paul C. Buff founder of Allison Research moved to Nashville and collaborated and later merged with a small audio company called Valley Audio. As Allison Research prior to moving to Nashville, he had connections to Pal Studios and Frank Zappa which helped to popularize Paul C. Buff’s circuits which in addition to the TransAmp included a VCA, the Gain Brain FET VCA compressor/limiter and KEPEX KEyable Programmable EXpander/gate. The KEPEX became notable for its use on the mix of Pink Floyd’s Dark Side of the Moon. As a studio FET compressor, the Gain Brain outperforms the Urei 1176LN for attack/release speed, meter accuracy, and size/weight. Even more so when the modules were remade under Valley People as the Gain Brain II and KEPEX II. In those days they also added the MaxiQ parametric EQ and began to switch from the early VCA to the EGC-101 modules and later to the TA-101 class A transistor array VCA to act as gain control in their modules. Later in the 1980’s the DynaMite compressor/limiter and DSP (De-essing Sibilance Processor) also came out in a card edge format, and Valley People began to move toward new designs with Michael ‘Doc’ Morgan designing 1RU format units with one or a few effects circuits incorporated in to them. That faithful early version of Paul C. Buff’s fully differential mic pre design lived on as the TransAmp continued to be used in Valley People and later Valley International modules that had a mic pre built in to them.
While they were made, and even after, these modules found their way in to the consoles of countless recording studios, and broadcast facilities.
Unfortunately for Valley People’s long term success, that was not their biggest competition. That was DBX and SSL, who made and implemented a few competing modular VCAs of sorts. Valley People was purchased and revived by PMI audio group in the 2000’s allowing for the release of a new API VPR 500-series format version of the Dyna-Mite compressor. While there has been no official rerelease of the TransAmp and may never be, SonicImageryLabs created their own version of a modern improved version of the TransAmp that can plug directly as an improved replacement. It uses modern surface mount devices and is not potted, so it is easy to see ‘what’s in it’. It includes several transistors and diodes, a pair of LS358 line driver style op amps, and an OPA1622 dual bipolar JFET Op-amp.
Sources:
https://www.lumafield.com/
http://zine.r-massive.com/valley-people-audio-manuals/
https://www.technicalaudio.com/pdf/Valley_People/Valley_People_Trans-Amp_LZ.pdf
https://www.oneflightup.com.au/allison-research
https://en.wikipedia.org/wiki/Pal_Recording_Studio
http://valleypeople.com/history.html
http://pmiaudio.com/history/
https://www.fivefishaudio.com/blog/transimpedance-amplifier-by-valley-people/
https://groupdiy.com/threads/antique-shop-find-rack-of-8-valley-people-trans-amp-lz-pres-pics.54944/
https://groupdiy.com/threads/valley-people-transamp-schematic.36495/