Hughes & Kettner Rotosphere MKII Review

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One of the products that marked the world of rock music back in the 60s and the 70s were the legendary Leslie rotary speakers.

Although intended for Hammond organ use, those clever guitar players managed to take it over and turn it into something of their own. But the sweet eargasmic rotary speaker sound becomes complicated when you realize that you have to carry that big thing around.

Luckily for all the lovers of rotary speakers, the technology has advanced just enough that you can have that effect in the form of a very compact and practical piece of gear that fits into an average pedalboard which you can carry without breaking your back.

The tone, however, is not easy to replicate, but for the guys over at Hughes & Kettner this was a challenge they gladly accepted, ultimately creating one wonderful unit called Rotosphere MKII.

This particular pedal is used by none other but Pearl Jam lead guitarist Mike McCready.



Before we start, we should remind you that this is actually a tube driven pedal. It features one 12AX7 tube that’s mostly used for guitar preamps or preamp sections of amplifiers. This makes it not only a great sounding piece of gear but also a dynamically responsive one.

There are three control knobs on Rotosphere: drive, output volume, and rotor balance. Now, this is not primarily an overdrive pedal, but it does create some distortion which is controlled using the drive knob.

But this being a tube effect, it does create additional distortion if the volume is turned up high. As for the rotor balance control, it blends and mixes the sound of bass and tweeter rotary speakers. There are also two LED lights next to the balance control indicating the speed of the treble and bass rotors.

You can find three quality foot switches on the front panel. First, the bypass switch turns the whole pedal on and off. Right next to it is a breaker switch, which is a pretty interesting and useful control.

With it, you can shut off the rotary effect and use the Rotosphere only as a tube preamp. When switched back on, it brings you back to your adjusted settings.

On the right side, there is is a slow/fast switch that lets you toggle between the speed modes of the pedal. This particular feature works with two additional controls on the left and the right side of the balance knob.

There you can find two small holes with screws in them and these can only be accessed with a small screwdriver. They control speeds of bass and treble speakers in the “fast” mode of the pedal.

On the back side of the unit, there is a selector switch that lets you use Rotosphere either as a guitar or keyboard effect. Right next to it, there are two outputs and two inputs, meaning that the pedal may be utilized in mono or stereo mode.

Another jack, labeled as “remote,” is used for external units like footswitches or MIDI controllers.


Taking a glance at the H&K Rotosphere, you immediately notice that it’s a quality built and pretty nice looking pedal with a silver front panel. It features the almost identical design of all the other of Hughes & Kettner’s Tube Tools units, such as Tubeman MK2 preamp, Tube Factor drive, and Reflex reverb.

One thing that stands out here is the famous Hughes & Kettner logo with blue lights. Through the transparent plastic part with the logo, you can also see inside the pedal, right where the tube is located.

As for the LED lights, they are all pretty noticeable and players won’t have any difficulties seeing all the needed functions turned on or off.

All in all, the Rotosphere will definitely be something that clearly stands out on your pedalboard.


The controls are pretty easy to follow through and there are many combinations for making your sound unique. The feature to use it only as an overdrive pedal is pretty useful and you can get some pretty great vintage tones out of it.

Although for fully adjusting the pedal you need a screwdriver and a little bit of patience, the Leslie speaker simulation is convincing, both in slower and faster modes.

As already mentioned above, with Rotosphere being a tube based pedal, there’s some dynamic responsiveness that you can get out of it, especially if you turn the drive or output knobs up.

And, another thing which comes as a neat feature for these kinds of effects – you can try out different types of 12AX7 or ECC83 tubes to get different sounds.

However, replacing a tube in one of these is kind of a headache since it requires you to take the whole thing apart, including the main circuit board.

And tube replacement is a must after long or frequent use. If you don’t feel confident enough changing it yourself, we advise you to consult a professional.

Despite all the great features and sound, we should point out another minor flaw – the input and output jack placement.

Average pedals have the input on the right side and output on the left, while Rotosphere has it the other way around. This might contribute to some additional cable mess on your pedalboard.


To put it simply: the sound is organic, the rotary effect is convincing, the build quality is amazing, and the pedal just looks great. You’ll just need to know that it’s not like the other pedals and is more of a higher intermediate or pro level piece of gear.

It is definitely worth every penny, especially if you are into the vintage sounds. There were some flaws that we listed, which are mostly just some minor issues, so if you’re looking for a good-quality Leslie emulator, then you won’t really go wrong with Hughes & Kettner Rotosphere MK2.


Video Demos of the H&K Rotosphere MK2

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