Op-2HD tube compressor Prototype.

Here's prototype number 2 in the development of a Storm Series compressor.  The first prototype had a lot of issues, distortion being the biggest one.  This one doesn't have any issues and sounds great.  I think at this point its ready to move forward with refining the design and look.  I'll have to sell this prototype in order to fund the advancement of the design.  It'll be available in the store section of this website under the used gear section later tonight. 

So what is it then?  2 tubes (12AT7, 12AX7) running at high voltage and 3 audio transformers are inside of this compressor.  It is based on my Op-2 Compressor pedal from a few years back, but this is radically better in every way.  More features, more headroom, more tone.  It is essentially an optical compressor, but different from usual in that a vacuum tube is responsible for creating the ratio by means of tube compression (distortion).  The compression knob is both the threshold adjustment and the ratio adjustment in one knob and it acts directly on the compression tube.  As you turn up the compression knob you increase the ratio and increase the amount of signal allowed to pass over the threshold.  There are controls for attack and release times, but they are a little interdependent.  A slower attack setting will result in a slower release time, but the release time switch has no affect on the attack time.  You can get a medium fast release with a slow attack, or a slow release.  You can also get a very fast attack and a fast release, or a slow release.  There is a side-chain low frequency bypass for the detection circuit.  There's more gain available in the tube makeup gain control than you'll likely ever need.  Your input signal level is not adjustable.  A hotter input signal will pass the threshold easier and compress more. 

This device runs on a 12V DC external line-lump power adapter (740mA draw). 

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