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Two Rock Bi Onyx 40 head

Issue #28

Two Rock has been with us long enough for the name to really mean something among amp purists. The US company's handmade amps would be classed as 'boutique' and I think their earliest amps are destined for cult status, in the same way that a Howard Dumble amp is lusted after today. In fact I recently saw an ad for a Two Rock John Mayer signature amp that was a very limited run and personally signed by the man himself. The price was $39,000. Out of principle, I would never pay $39,000 for a guitar amp, but people do.

Our review amp is a lot cheaper and is part of a range newly launched by Two Rock. It's called the Bi Onyx and it is aimed at players who enjoy a channel switching amp that is ultra flexible and versatile. That'll be me then! Our review amp was rated at 40 Watts but you can get Bi Onyx heads rated at 50 and 100 Watts and there's also a 40 Watt combo version. The 40 watt model is equipped with four 6V6 tubes, while the 50 and 100 Watt versions come with the option of either EL34s or 6L6 power tubes. 40 Watts is easily loud enough for most situations and when it comes to Watts it's not so much about sheer volume as about clean headroom. Headroom is good if you run any sort of modulation effects in the effects loop of your amp, because you want the output tubes to stay clean at stage volumes, so that your delays and reverbs to stay clean. This 40 Watt version certainly seems loud enough and I am sure the effects loop would handle whatever modulation effect you might want to use.

The two channels on this amp each have independent controls for you to set the EQ and how much gain, volume and boost you want. You could say that it’s a clean channel, but by adjusting the pre-amp gain, you can add crunch to the clean channel to make it growl. There are definitely some nice touch sensitive tones on this channel, and if you are the sort of touch player that uses the volume pot on your guitar, then you will love this channel. The dirtier channel 2 can be crunchy or produce some modern hi gain depending on how you set the pre-amp and master pots. The gain sound had a real tightness at the bottom and bark around the mids. Two Rock makes a point of saying that the transformer in this amp is a new design that is actually meant to give a tighter than usual low end and broader mid and high. I wish I knew enough about electronics to know how different the transformer design is, but I can certainly hear some mojo going on.

Another cool feature on the Bi Onyx is that each channel has an independent boost control, which is foot switchable. Set how much boost you want on each boost pot on the front of the amp and kick it in with the foot switch. It seems to be voiced to give a lift to the sound rather than take your head off, but it almost makes the two channel set up into a four channel amp and it would work great for giving a lift for your solos.

There is an onboard analogue spring reverb which can add a little something behind your tone. I am rarely a fan of on board amp reverbs and prefer to run something digital and studio quality sounding in the loop. This reverb sounds OK as long as you don't over cook it, and sounds better to me when you feel it rather than hear it. I am just not a spring reverb type of player, but if you are then you won't be disappointed!

To add more versatility there is a contour pot on the front of the amp that acts like a presence control, but with more of a shift in how light or dark sounding you want the overall tone to sound. Imagine moving the mic on a speaker cab to adjust the sound when recording, and you are in the ball park of what the contour control does.

Lastly, this amp is equipped with a new speaker output feature that enables you to use multiple cabs at the same time, even if they are of different impedance. This would unlock huge tonal versatility if you are lucky enough to own a few cabs with different speakers. Most 4x12 cabs are 16 Ohms rated, and many 2x12 cabs are 8 Ohms so if you have a local stadium gig coming up, tell your roadie to set the lot up with the Bi Onyx driving it all. Or just put your 1x12 and this head in the back of your car for the local club gig because the Bi Onyx can do it all. I cannot think of another amp manufacturer that has this feature multiple cab feature. It's very cool.

As you would expect from Two Rock, this is a versatile, well thought out, great sounding amp. It's not cheap, especially if you live outside of the United States, but then Two Rock products are up there with the best you can get. If you're the sort of player who can hear and feel the difference then the price may not be such an obstacle. Generally it's worth the extra for something that is the real deal!

Issue 28 Cover

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Peter Green / Ivar Bjørnson

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