Rev. 1 shown (no trim on front on this pic).
Just got mine today, here are my initial thoughts. And a pic of the insides!
Sounds great and has very flexible options. Just what I hoped for. Low self noise, especially for a unit like this*. Good default calibration for a tube unit (±0.1 to 0.2 dB), depends on how hard you push the serial circuit or add in parallel of course. There's a front panel LR trim pot on this new revisions of the HG-2.
Used it on the first track today. Was able to increase midrange presence and bass definition on a hip hop track. Pulled up the vocals nicely and added a bit of stereo width, but the low end phase was still well centered.
I liked the air lift at first, then removed it a bit later, but it'll come in handy on other tracks. Otherwise I got the expected change in crest factor, peaks controlled slightly, RMS increased relatively.
The way the pentode pushes into the triode takes some getting used to from a workflow perspective, but I never expected to fully wrap my head around the practical use of the unit in the first hour. Parallel saturation can really take the sound OTT, so I didn't use it on this track, where I needed fairly clean 808s. Furthermore, engaging the alternative tube in the parallel chain takes the distortion up yet a notch. Since it's parallel it's easily blended at the correct level regardless of how aggressive it is.
Not as easy to recall as I could have wished for, but not as bad as I could have feared. A very low level hum from the unit itself in the rack (not a problem in the audio), which was not unexpected though. Might not be audible in most studios as it's close to very low noise floor of my room.
On/off on the back, on/off/standby on the front, parallel in/out + hard bypass on the front. Lotsa options, but I tend to use my Dangerous Liaison for any switching anyway.
All in all I'm very pleased and looking forward to playing around with this new toy. Arrived just in time for an album I'm doing tomorrow where the producer asked for added grit and dirt at the mastering stage. I shall oblige him.
PDF manual (older rev., no trim)
http://blackboxanalog.com/wp-content...al-REV-3.0.pdf
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