Millennia Music & Media Systems’ HV-37 is a 1U rack cabinet that contains two hardwired HV-35 microphone pre-amp circuit boards—the same boards that go into modules designed to fit the 500 Series “lunchbox” racks. The HV-37’s performance is identical except it’s more cost-effective than buying two HV-35s because the HV-37 includes a built-in switching power supply.
The HV-35 module is a direct-couple amplifier design that uses no transformers in the audio path. Input and output transformers used in microphone pre-amps offer reliable, galvanic isolation and protection from the vagaries of the input microphone sources coming into them (faulty grounding, power line noise etc.) and also of the output line the pre-amp drives. But this protection comes at a cost with the transformer’s extra expense, size, bandwidth-limited frequency response, non-linear operation and distortion—particularly at high operating levels coloring the sound.
Here at my Tones 4 $ studios, I have several microphone pre-amps to choose from when recording music but this is my first direct-couple model to evaluate and compare. I recorded vocals, percussion, DI electric guitars and bass and the HV-37 was truer to the source with better definition in the bass and a significantly more open and airy top end.
So I am glad to hear and compare the HV-37 in my world of what I’ve gotten used to with microphone pre-amps. At about $1,600 MSRP for two channels, it makes a great alternative to the transformer and/or tube microphone pre-amps in my recording signal chain when I am looking for super clean, pristine and accurate amplification.
By Barry Rudolph
miniBio: Barry Rudolph is a recording engineer/mixer with over 30 gold and platinum RIAA awards to his credit. He has recorded and/or mixed: Lynyrd Skynyrd, Hall & Oates, Pat Benatar, Rod Stewart, the Corrs and Robbie Nevil. Barry has his own futuristic music mixing facility and also teaches recording engineering at Musician’s Institute, Hollywood, CA. http://www.barryrudolph.