The HOC500 is labeled as a "parallel opto compressor," and is a cousin to Hamptone's HOC1 half-rack version [Tape Op #100]. Adapted for a 500 Series chassis, there's a lot less room for controls, so a unique feature set has been adapted here. A pair of house-made opto cells are run through Hamptone's testing, and their characteristics are logged for precise matching so that the desired linearity of compression can be programmed specifically for each unit. How many companies build units at this level of detail? The Hard Wire I/O switch is a must. I'm so annoyed by the number of compressors that do not allow for complete bypass of the electronics – how am I supposed to set my mic levels if I can't turn off the compressor first? The six-segment LED metering is superb, and meters are something I always count on to help me set compression (before using my ears, duh). The dB reduction is clearly labelled, and it’s easy to understand what this unit is doing from across the room. Alternate metering level setups are adjustable via internal jumpers.
The HOC500’s three knobs, VOL, MIX, CMP LVL, handle the main functions. I found myself turning the MIX knob all the way right (fully wet) to hear only the compressed signal, getting either a softly compressed setting or a full squish with the CMP LVL knob below, and then dialing MIX back until the DRY signal added a bit of openness or clarity as needed for the part. Then I'd adjust VOL to set the appropriate makeup gain level for feeding the console or Pro Tools track while popping the Hard Wire I/O switch in and out to make sure I wasn’t feeding a ridiculously hot or quiet signal. One smart little feature is the recessed Link switch on the unit’s front panel; take a tiny screwdriver (or similar tool) and pop it on or off. Linking is set up via a standard 2.1 mm cable that can be plugged in between adjacent units when racking. One might think the HOC500 offers few options for attack and release times beyond the Rate switch's Slow or Fast settings. However, pulling the unit out of the rack, studying the printing on the side, and noting the instructions for configuring the four trim potentiometers will offer an unlimited number of variations for both Slow and Fast settings. (Don't hot swap 500 Series devices!)
On an overdriven bass, I wasn't sure that there was any compression left to add, but I tried anyway. The HOC500 added some nice depth to the low end and tugged some of the bass crunch down for a nicer tone. I took a vocal from an in the box mix that I was struggling with, piped it out to the HOC500, and recorded it back into the session. With occasional -15 dB peaks of compression, it began to line itself up and stay much more focused in a dense mix. For an album mix with some busy drumming, I loved this unit on tom tracks. There was something about the way the attack was emphasized with the stock attack/release settings that made them hold up in the mix quite well, and adding back in a little dry signal helped fill in the bottom end. Super cool! As a stereo (unlinked) parallel drum bus compressor, the HOC500 rocked. Hitting the reduction hard added excitement to the tone and an evenness to the hits.
In the past, I haven't been much of a fan of 500 Series-based compressors, as they usually seem to either lack enough controls to be useful (one-trick ponies) or have too many controls and are hard to figure out or set with my bass player's fingers. Hamptone's HOC500 is a perfect adaptation of what Scott Hampton learned from designing the original HOC1 rack unit over a decade ago, with functions distilled down to a very usable and useful unit. The price point is incredibly fair for a boutique compressor of this quality, so I urge everyone to check out the HOC500.