Crazy Tube Circuits Achieves Engineering Nirvana with 3 Separate Analog Compression Circuits in a Single Compact Enclosure - the Phi Golden Ratio V2
It’s been a while since the V1 Phi Golden Ratio Compressor was discontinued, while all that time Christos of Crazy Tube Circuits (CTC) has been re-engineering, evolving and refining that already formidable compressor pedal to accommodate a third OTA compression circuit - in a more compact enclosure no less!
The predecessor was a BB-sized affair and contained the FET and OPTO circuits. The 7 controls were otherwise pretty similar - with a toggle-switch for the Circuit selection, and 6 variable knobs - where Input back then is now labelled Threshold on the V2.
I know of no other Compressor pedal that contains 3 separate analog compression circuits - certainly not in such an elegant form-factor. Each of its 3 circuits delivers an entirely different flavour of compression with slightly different characteristics and tolerances, as I will endeavour to detail.
Controls - Volume, Blend, Ratio, Release, Attack, Threshold.
- Volume : set the output level of your compressor unit. Use for makeup gain or as a clean boost
- Blend : set the perfect mix between dry-uncompressed signal (100% counter-clockwise) and wet-compressed signal (100% clockwise). Add punch and sustain without losing the dynamics of your signal
- Ratio : adjust the amount of compression/gain reduction. Range from full counter clockwise to full clockwise - FET : from 1.5:1 to 10:1 | OTA : from 1 :1 to 20:1 | OPTO : from 1.5:1 to 15:1
- Release : set the time until compression (gain reduction) stops and returns to the initial level. Time increases as you turn clockwise - FET, OTA circuit range : 50ms to 4s | OPTO circuit range : 80ms to 4s
- Attack : set the time until compression (gain reduction) begins. Time increases as you turn clockwise - FET, OTA circuit range : 1 ms to 30ms | OPTO circuit range : 3ms to 33ms
- Threshold / Red LED compression indicator : adjust the amount of signal that goes into the compression detector circuit. When the Red LED flashes brighter compression is engaged. Higher levels of signal will result in more compression / LED brightness
Bypass footswitch (soft-click) : engage or true bypass your effect via a high-quality relay. White LED indicates that the compressor effect is engaged
The 3 Types of Compressor Circuits Onboard
FET COMPRESSOR : This is a feedback detector/control compression circuit that relies on a FET transistor for gain reduction. It adds a distinctive color to the signal and can be set for super-fast response, but it may also introduce a bit of distortion
OTA COMPRESSOR : The majority of guitar compressors use this technology. Our interpretation uses a feed-forward detector circuit thus being able to 'squeeze' things harder, ideal for catching fast transients and limiting. It is the most controllable circuit with punchy and direct sound
OPTO (OPTICAL) COMPRESSOR : A hand selected photocell combined with a feedback detector circuit offers smooth attack and release characteristics - resulting in very musical and organic compression even on extreme settings. It can also be set very neutral so that you won't be able to tell when it's on but you sure going to miss it when it's gone
"Phi will fatten up your tone even with no compression added. With the parallel compression technique of blending the compressed signal with the original - uncompressed signal, you will experience clarity and precision only found in studio recordings. It features superb low-noise-floor performance and full frequency response - making it ideal for guitar, bass and virtually every stringed instrument either in the studio or on the stage. An internal switch selects between 9V or 18V DC operation from a standard 9V DC power supply. Use the 18V setting for increased headroom and enhanced compression characteristics."
Internal Controls
FET COMPRESSION CIRCUIT RATIO/DISTORTION TRIMMER (located on bottom of PCB). This control will become handy when using high output pickups or bass guitar. Use a tiny/long screwdriver to adjust audible distortion of FET compression. Trim setting also affects compression ratio range of the FET compression circuit; it does not affect OTA and OPTO circuits. You will hear less distortion and lower compression ratio as you turn clockwise
HEADROOM SWITCH. Select 9 setting for standard 9V DC operation or 18 for increased 18V headroom. 18V DC is provided by an internal charge pump circuit. DO NOT plug a 18V DC power supply
OUTPUT / MAKE UP GAIN INTERNAL SWITCH. Select between High or Low output / make up gain circuit. High make up gain setting adds an extra 8dB boost to the output signal
Demos
Final Thoughts
I really cannot see a more versatile Compression unit out there than this - in terms of having all those different flavours onboard. And while there are other excellent Compressors with slightly more controls and fine-tuning - like say the Becos FX CompIQ Stella, or different combination effects like the JA Bloom. There don't seem to be any quite as prodigiously potent as the Phi Golden Ratio V2.
Even though I have quite a hitlist of compressor candidates I'm seriously impressed with this one - and it likely goes to the top of my compressor acquisitions list. The ability to compare and contrast FET, OTA and Optical Compressors all in one unit is simply extraordinary.
It has all the essential controls you need - possibly you could say some sort of further EQ would be a nice to have - but it's by no means a necessity as each of those compressions have their own texture and tonality integral with their output.
The price for this engineering marvel is just €229 / $249 - for essentially 3 wholly different compressors. I expect these to sell pretty fast on the Crazy Tube Circuits Webstore. So you might have to get your skates on to secure one from the first batch.
Anyone looking for a new Compressor/s?
