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Crazy Tube Circuits Unobtanium RAW Overdrive Pedal with OC45 transistors

Inspired by two mythical and rather unobtainable pieces of gear -- The Klon Centaur and Dumble -- the Unobtanium has become a standout in the Crazy Tube lineup. Pushing the envelop even further, Crazy Tube Circuits has tweaked it even more for the new Unobtanium RAW. Along with a re-voicing of the Dumble side, the the RAW features NOS Mullard/Valvo OC45 Germanium transistors on the "K" side of the pedal; not just for additional gain but also for clarity and excellent turndown.

The Unobtanium RAW does not replace the Unobtanium, and the RAW will be produced as long as the stock of OC45 transistors last.

Klon Side - The Klon was heralded as one of the first "transparent" overdrives and the Unobtanium version is an open sounding pedal that can run from slightly hairy to pretty heavy crunch that thickens nicely as you twist the dial. Engaging the Mod mode now switches from germanium clipping diodes of the original design to the rare NOS OC45 transistors. The OC45 is the transistor of the original Fuzz Face and other early fuzz and distortion pedals. While they can produce more gain and and sustain, the OC45's have a slightly leaner tone with more detail, and a less forward midrange bark than the original design. If a regular Klon strikes you as sometimes a little dark, then you'll probably favor the Mod mode, which we do. And the beauty of the OC45's is that they clean up very nicely; and you can have the gain pretty jacked and ride the volume control to shape your sound. 

The Buffer/True bypass option is another useful feature, and how it affects your tone will depend very much on your pedalboard, cable runs, etc. Buffers help to compensate for signal loss from complex pedal boards and cable runs, but they can also induce a good dose of high frequency presence. Whether you "need" one is a matter of taste and how it affects your overall tone. 

Dumble Side - Your chance of winning the lottery is slightly better than owning a Dumble, but the Unobtanium gives you twin Dumble Unicorns, the Overdrive Special and the Steel String Singer. CTS tweaked the circuit to be more "rock" similar to the rock/jazz toggle on some Dumble amplifiers. We still lean towards the clarity and note definition of the SSS, which gave us abroad range of musical grit and grind that was clear and articulate. The ODS has a deeper, huskier voice that really sings, with a thicker midrange that will beef up single coils. Neither setting gets really compressed unless you bury the gain knob, and with both a pre-boost emphasis control and post-boost tone controls you'll find a happy setting with any guitar. 

You can stack both pedals, although you can't switch the order of them. And the very smart SND and RTN jacks allow you to place pedals in between them, so you are not stuck with Siamese Twin Unicorns. Lastly, the optional XT footswitch (about the size of a large marshmallow) provides remote access to the Stock/Mod and SSS/ODS toggles, giving you a four-voice stompbox that is all footswitch accessible. And any passive latching 1-button footswitch will work.

Accuracy to the originals notwithstanding, this is a great sounding pedal that provides multiple options for a broad range of almost-clean, overdrive and all-out crunch that is tastefully musical and rich. Frankly both sides stand on their own, and wether you think of the Dumble side as a amp model or just a great sounding overdrive/distortion pedal is up to you. Punk rockers and hard core fuzz fans may look elsewhere, but the for the rest of us there is a lot to like. Due to the cost of the OC45 components, the RAW comes at a premium to the regular Unobtanium. But shop for any pedal with rare NOS components and you'll find higher pricing. Considering the overall flexibility of the Unobtanium, the up charge for the Germanium transistors seems well worth it. 

In the words of Crazy Tube Circuits....

We've put your dream tones in a box!

Unobtanium was inspired by 3 of the most mythical and sought-aer pieces of music gear and combines their ultra-rare sonic elements. A magical tone overdrive meets two legendary amps. We have accurately recreated the circuit of the high headroom OVERDRIVE with the mystical blend of clean and overdriven tones. The RAW edition is the first pedal of its kind to feature germanium transistors in the clipping section of a K-style circuit producing higher gain, naturally compressed tones. RAW AMP section uses an all-analog circuit to capture the powerful side of two legendary tube amplifiers. From big fat clean to raw singing overdrive with blooming harmonic overtones. A passive effects loop gives you the option to connect your beloved pedals between your overdrive and amps in a box, building your ideal rig.


gain: Controls the amount of drive. From transparent clean to high headroom thick overdrive as you turn clockwise.
treble: Controls the amount of high end frequencies, brighter as you turn clockwise.
volume: Controls he output volume. Features enormous amounts of output volume making it ideal to also be used as a preamp/booster.

Stock: The original mythical drive circuit produced by the fabled germanium diodes.
OC45: Higher gain tones produced by New Old Stock Germanium transistors in the clipping section.

Bypass toggle switch: Select between the original BUFFER bypass, adding clarity to your signal chain and running long cables without affecting tone, or TRUE bypass via a high quality relay.

AMP ( see note 2)
Gain: Controls the amount of compression/drive. From clean boost to raw singing overdrive.
Emphasis: Adds gain and adjusts presence and bottom end response before the signal is overdriven. Brighter, tighter and enhanced pick attack as you turn clockwise.
Tone: Controls the amount of post-overdrive high end frequencies, brighter as you turn clockwise.
Volume: Controls the output volume. Features enormous amounts of output volume making it ideal to also be used as a preamp/booster. voicing toggle switch or external XT footswitch (see note 3): Select between different amp voicings.
ODS: Raw singing overdrive with enhanced mid frequencies and blooming harmonic overtones.
SSS: “Clean” drive with natural organic compression.

Internal trimmers:
ODS BOOST trim: Add up to extra 6db of output gain / volume boost with a similar effect of pushing the power tubes harder. Only affects ODS voicing.
SSS LOW trim: Adjust low end response of SSS voicing.


↓/↑: mono instrument input/output.
Passive series effects loop. Connect your beloved pedals between OVERDRIVE and AMP or use the two sections as separate and independent effects. SND is the output of the OVERDRIVE section, RTN is the input of the AMP section. SND is connected to RTN when no jacks are inserted in the effects loop.
XT (note 3) : Connect to an external footswitch to control AMP voicing. Use standard mono instrument cable (TS jack) with Crazy Tube Circuits XT footswitch or a passive latching switch (non-powered). Do not use an active switching circuit as it won’t operate properly and can cause malfunction to the pedal.


(1) The sonic difference in voicing is most noticeable in higher gain settings. You may experience a difference in output volume between the two voicings.
(2) AMP section is an amp-in-a-box overdrive circuit. It does not feature a power amp or a speaker simulation circuit. It is intended for use with another amp/speaker cabinet. We recommend using a separate speaker simulation device when going direct.

(3) External footswitch bypasses onboard voicing toggle switch operation.
Left side’s LED turns half red when in ODS voicing.
A barely noticeable momentary pop is perfectly normal when AMP voicing switch changes state.

Power supply: 9V DC center negative, regulated / stabilized (not included). Isolated power supply is recommended for best performance. Max current consumption 83mA