5
Introduction
A Letter from Bill Putnam Jr.
Thank you for purchasing the SOLO/610 Classic Tube Preamplifier and DI Box. The SOLO/610 is
inspired by the microphone preamp section of the 610 console designed by my father, M.T. “Bill”
Putnam, in 1960. The 610 was a rotary-control console and was the first console of a modular design.
Although technologically simple compared to modern consoles, the 610 possesses a warmth and
character that has kept it in demand for decades. As a prominent part of my father’s United/Western
Studios, the 610 was used on many classic recordings by Frank Sinatra and Sarah Vaughan. The
Beach Boys Pet Sounds, the Doors LA Woman, and Van Halen’s debut album were all recorded on the
610. The legendary Wally Heider used the 610 in his remote truck for many of his best known live
recordings. At Ocean Way Studios (formerly United), the 610 is lovingly preserved and still used in
Studio B.
Most of us at Universal Audio are musicians, recording engineers, or both, and we wanted to build a
mic preamp that we’d be delighted to use ourselves. We love the recording process, and we really get
inspired when the basic tracks are beautifully recorded. Our design goal for the SOLO/610 was to
capture the original character of the 610, creating a preamp that would induce that “a-ha” feeling
we’ve felt when hearing music recorded in its most natural, inspired form.
The controls of the SOLO/610 are simple and essential: we added only those features required for
practical use without needless duplication of functionality found elsewhere in most studios. The
transformers and tubes received much of our R&D attention. We settled on a transformer design
featuring double-sized alloy cores with custom windings. Our tubes are carefully selected and tested
individually. This extra effort is well worth the time and cost because the result is a truly outstanding,
easy-to-use mic preamp!
Developing the SOLO/610 – as well as Universal Audio’s entire line of quality audio products designed
to meet the needs of the modern recording studio while retaining the character of classic vintage
equipment – has been a very special experience for me and for all who have been involved. While, on
the surface, the rebuilding of UA has been a business endeavor, it's really been so much more than
that: in equal parts a sentimental and technical adventure.
We thank you for your support, and we thank my father, Bill Putnam.
Sincerely,
Bill Putnam Jr.
