Crazy Tube Circuits Unobtanium review: A dual overdrive that crams two legends into one box

Effects pedals are an absolute bloody pest. They cost money, they take up room on your ‘board, and each one needs its own power supply. So we’re pleased to report that the Unobtanium, an extremely classy dual overdrive from Greek boutique builder Crazy Tube Circuits, can help with at least two of those issues.

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We’re seeing more and more dual drive pedals these days. Saving both space and power cables, it’s an arrangement that makes a lot of sense… as long as both halves offer sounds that you actually want. Well, in this case the two key words are Klon and Dumble – and who doesn’t want a bit of that?

Of course, there are already lots of ‘klones’ out there, but pedals emulating the creamy tones of a Dumble amp – or indeed two Dumble amps – are not so commonplace. And if you like the idea of having both of those quasi-mythical tonal titans replicated in a single unit, your search almost certainly begins and ends with the Unobtanium.

On the right-hand side of this stone-grey pedal, we find the classic three-knob array of the Klon Centaur – plus a couple of extras. One is a switch for true or buffered bypass, a pedalboard-friendly feature that you might recognise from the later Klon KTR; and the other lets you flip between stock and ‘modified’ modes, the latter promising more gain and less compression.

Over on the left, our volume, gain and tone controls are joined by one marked ‘emphasis’ – adding gain and presence before the signal is overdriven – and another toggle switch, this time for choosing between two different Dumble models: the Overdrive Special and the Steel String Singer. There’s also an input for doing that job with an external footswitch (not included), and rounding off the Unobtanium’s feature set is an effects loop, so you can place other pedals between the two drive circuits.

By the way, if you’re wondering just how unobtainable the originals of these two items are, here’s some context: at the time of writing, used Centaurs were going for between £3,000 and £5,000 on Reverb; and an American dealer was selling a Dumble Steel String Singer for $220,000. Bit rich, eh? If you ask nicely, maybe they’ll take your house in part-ex.

In use

To avoid stepping on other people’s brand names, CTC calls the two sides of this pedal simply ‘overdrive’ and ‘amp’. But just to be clear, it is purely a drive pedal, designed to be plugged into a real amplifier – so let’s wheel out our favourite clean-chimey combo and start jamming.
The Klon side is up first and our immediate impressions are… well, Klonny. The lower mids are nicely warmed up, the treble is gently dampened down, and it has that natural cuddliness that softens the spikiest of single-coils and just makes everything feel better.

Does it compress as sweetly as our trusty J Rockett Archer? Not quite, but this is perhaps a slightly more transparent take on the Centaur sound than you’ll get from most klones… and for some people that might not be a bad thing. We just wish the ‘mod’ switch had a bit more of an impact – at some settings the difference is barely noticeable.

And the Dumble side? In some ways it’s surprisingly similar – again we’re talking about low/medium-gain overdrive with a tonality that’s on the darker side of neutral – but the contrast is clear. It is indeed more amp-like, with plenty of low-end beef but above all supreme clarity and buttery smoothness.

SSS mode is where the really natural stuff happens, but it’s worth flipping to the ODS setting for something with a thicker midrange (and a pink LED instead of white). In either position, ‘emphasis’ works brilliantly in tandem with the tone knob to offer varying flavours of controlled crispness up top.

Putting a delay pedal in the loop between the two halves of the pedal means its repeats will be bigger and clearer with the Dumble drive than they are with the Klon. That could be a useful feature in some cases… although, this being an overdrive pedal and not an amp, we’d normally be inclined to put delays and reverbs after it anyway.

The ability to engage both sides of the Unobtanium together takes our total of footswitchable sounds up to three – and ‘both’ might be our favourite, retaining all the benefits of the two individual drives but doubling up on gain. This is the place to come for your big solo, though that’s not to say it can’t handle a spot of punky chugging too.

Not quite ready to go full ‘oligarch spending spree’ but keen to get a taste of the fabled Klon and Dumble magic? This is surely your best obtainable option.

Key Features

• PRICE £249
• DESCRIPTION Dual overdrive pedal, made in Greece
• CONTROLS ‘Amp’ volume, gain, tone, emphasis and ODS/SSS model switch; ‘overdrive’ volume, gain, treble, stock/mod switch and true/buffered bypass switch
• FEATURES Effects loop send and return, TS footswitch input for amp model; powered by 9-volt mains supply only
• DIMENSIONS 123 x 98 x 52mm
• CONTACT crazytubecircuits.com, face.be

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