This recreation of a Bill Putnam classic brings back to life the qualities of a long-gone era — and does so in a truly uncompromising fashion.
Hannes Bieger

Photos Hannes Bieger
Bill Putnam’s 176 Valve Limiter, the predecessor of the ubiquituous UREI 1176LN, is among the most coveted and sought-after vintage compressors. It is rare these days even in its motherland, the United States, but it’s virtually impossible to source one on the European side of the pond. Over here, only a handful of studios can count themselves lucky enough to possess one (and even fewer two) of these valve limiters.
But despite their rarity, the Universal Audio (UA) 176 and its predecessor, the 175, played an important role in the evolution of the dynamics processors we rely on today. When they were introduced in around 1960, Bill Putnam’s 2U limiters were not only among the most compact of outboard dynamic processors, they were also among the most versatile. Most of the limiters of this era, by manufacturers including RCA and Gates, are bulky 6U monsters, which, from today’s perspective, mostly can be deemed ‘one-trick ponies’. In contrast, the 176 offered four selectable ratio settings and variable attack and release controls. It remained in production for most of the 1960s, until it was replaced by the 1176, the first commercially available American-made transistor-based compressor.
When I visited UA in Santa Cruz back in 2009, I asked them about a possible reissue of their valve compressor, but they seemed reluctant to commit to this endeavour. Happily, then, Retro Instruments have come to the rescue of those who can not obtain — or afford — one of the scarce original units. Retro’s Phil Moore has received much praise for his first product, a reissue of the Gates Sta-Level, and his recreation of the 176, reviewed here, has gained an enthusiastic following in quite a short time, too: “Bill Putnam would smile!“, as Chris Lord-Alge put it. So, find out just why the Retro 176 might have put a smile on the face of the inventor...
Overview

The rear panel hosts all the valves and transformers.
The rear panel hosts all the valves and transformers.
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