5
Introduction
A Letter from Bill Putnam Jr.
Thank you for purchasing the Model 4-710d Four-Channel Tone Blending Mic Preamplifer — Universal
Audio's new digital hybrid product. The 4-710d combines four channels of our Model 710
Twin-Finity™ preamplifier with eight channels of pristine analog-to-digital conversion and adds a
complement of modern convenience features, all in a 2U, all-metal chassis at an amazing price.
Our all-original 710 Twin-Finity preamp with Tone Blending has proved to be wildly popular among
engineers, producers, and artists seeking a broad palette of sounds from clean to warm in a single,
affordable unit. The innovative preamp design of the Model 710 combines both the classic retro
warmth of UA tube design and the transient bite of solid-state. The 710 was created specifically to
add the tonal versatility and sonic inspiration missing from generic audio interface preamps. The key
to its sonic flexibility lies in its innovative circuit design, featuring a solid-state transimpedance input
amp simultaneously driving separate, phase-aligned tube and solid-state gain stages, which are then
summed to a single output. The mix between the single-ended class-A triode tube stage and solid-
state transimpedance stage is controlled via a unique “Blend” knob. Blending is continually variable
between 100% tube and 100% solid-state offering a practically infinite range of unique preamp tones
and the ability to easily dial in your own signature sound.
With the 4-710d, we've added even more value to the 710 mic preamps. Each channel includes an
1176-style compressor; this dynamics circuit sounds incredible and provides yet another dimension of
available sounds. For flexible signal routing and external processing, the 4-710d also includes
send/return jacks in each preamp that can be individually switched via the front panel.
The 4-710d facilitates easy integration of analog signals into your digital world with its built-in high
quality 8-channel A/D converter. Selectable sample rates from 44.1 to 192 kHz, digital output via ADAT
optical or AES/EBU via industry-standard DB-25 connector, and flexible low-jitter clocking options
make it easier than ever to get mic, line, or instrument signals directly into your DAW with a minimum
of hardware and fuss. The A/D converters include LED metering, and an 8-channel soft limiter helps
prevent digital overs.
Most of us at Universal Audio are musicians and/or recording engineers. We love the recording process,
and we really get inspired when tracks are beautifully recorded. Our design goal for the
4-710d was to build a hybrid mic preamp and A/D converter that we would be delighted to use
ourselves—one that would induce that “a-ha” feeling you get when hearing music recorded in its
most natural, inspired form.
Developing the Model 4-710d – 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, and we thank my father, Bill Putnam.
Sincerely,
Bill Putnam Jr.