Kaluna guitar pedal

Whoever said making stompboxes isn’t rocket science obviously hadn’t heard of Valbruch pedals, which are actually designed by a rocket scientist. 

Well, perhaps not a rocket scientist exactly, but Dr Henning Vahlbruch is professor of Gravitational Physics at the Albert Einstein Institute, and you don’t get a rocket off the ground without a deep knowledge of gravity…

Hand-built in Germany, the range currently comprises 13 different designs and features a unique switching technology designed by the prof. 

The Magnetic Transducer Button (MagTraB) switching works as follows: as you push the footswitch button the position of a magnet inside it is measured by a sensor; this sensor sends information via a micro-controller to a relay that does the actual switching.

The MagTraB system is said to be indestructible and capable of an almost infinite number of switching cycles, all with no mechanical switch clicks.

buffer on LED, dynamic processing LED

Trevor Curwen has played guitar for several decades – he's also mimed it on the UK's Top of the Pops.

Firstly it gets a new 3-way Structure switch - which allows you to select the stock ’V1’ voicing of the predecessor, as well as a ’Hot’ Higher Gain voicing, and a ’Low’ Lower Gain voicing.

Secondly the Kaluna now has an over voltage protection circuit which safeguards the pedal in case you inadvertently connect it to a power supply which exceeds the maximum 9 Volts.

You of course have everything that made the the original Kaluna so great - including that superbly dynamic and touch sensitive side.

A simple programming procedure also allows you to have the pedal power up in either On or Bypass mode.

In use, the switching is indeed dead silent, however, I did initially experience a problem with it not switching on/off reliably. A buffer? Another feature is that you can set a pedal so that it powers up either on or bypassed – very practical for ‘always on’ pedals or any in switcher loops.

Vahlbruch High Voltage Tube Drive

The Kaluna is a valve-based overdrive that runs from a nine-volt supply, although you’ll need a 500mA output on your power distributor to get its ECC83/12AX7 glowing away through the grille. 

With Drive at minimum, the Volume knob will give you a decent cleanish boost in about the last third of its range, but the Drive knob is capable of many shades of drive through to saturation as it pushes the valve. 

A powerful three-band EQ – Bass, Middle and Treble, each with up to 12dB of cut and boost – offers plenty of sonic sculpting capability, particularly in the midrange, to place the drive in the mix or to tune it to perfectly complement your amp.

Although there are some really driven tones available from the pedal, our preference is with the Drive at lower levels (and the rest set accordingly) in that role of transparently adding an extra switchable channel to our amp, all with a sensitive amp-like response to pick attack. 

Verdict: It ain’t cheap, but it’s real valve overdrive that can easily slot onto a pedalboard.

Specs

• PRICE: £295
• ORIGIN: Germany
• TYPE: Drive pedal
• FEATURES: True bypass, ECC83/12AX7 valve
• CONTROLS: Drive, Volume, Bass, Middle, Treble, Bypass footswitch
• CONNECTIONS: Standard input, standard output
• POWER: 9V DC adaptor (not supplied) 500mA
• DIMENSIONS: 120 (w) x 100 (d) x 48mm (h)

Vahlbruch SpaceTimeTap Delay

The SpaceTimeTap features digital repeats, while the dry signal remains resolutely analogue in a parallel path through the pedal so there’s no messing with your original tone. 

While the Time, Repeats and Mix knob are standard for any delay pedal, you do get some adjustment of the sound of the repeats via a three-way tone switch that reduces top-end. 

The Bright setting gives you the most clarity with repeats that naturally mimic your guitar tone, while the Mellow and Dark settings are progressively less bright and melt away really nicely into the ether.

With probably the three most-used time divisions, the tap tempo footswitch is a practical asset and its MagTraB switching works brilliantly in a tap tempo context, delivering what might just be the smoothest we’ve seen in a delay pedal. 

While you could get a decent multi-program delay pedal for the same price, this pedal’s virtue is that it just does the essential but does it so very well.

Verdict: Basic facilities for the price, but it scores on sound quality and simplicity of use.

Specs

• PRICE: £235
• ORIGIN: Germany
• TYPE: Delay pedal
• FEATURES: Selectable true or buffered bypass, selectable trails, 600ms max delay time, tap tempo, available with either creme or black knobs
• CONTROLS: Time, Repeats, Mix-Level, Tap Division switch (eighth, quarter, dotted eighth), Tone switch (Mellow, Bright, Dark), Tap Tempo footswitch, Bypass footswitch, internal true/buffered bypass switch, internal ‘kill dry’ switch, internal ‘trails on’ switch
• CONNECTIONS: Standard input, standard output
• POWER: 9V DC adaptor (not supplied) 60mA
• DIMENSIONS: 120 (w) x 100(d) x 48mm (h)

Vahlbruch Quantum Compressor

What do you like at the front-end of your signal chain?

And thanks to how the tube is configured in this circuit, the Kaluna’s touch responsiveness makes it great as a “leave it on” pedal if you prefer to sweep between cleaner and dirtier textures with the guitar’s volume knob.

Kudos to the Kaluna’s sweet tube tone and responsiveness to player dynamics, as well as its unique bypass switching and quiet operation.

He also wrote the first book on vintage effects pedals, Stompbox.  

A unique feature of the Kaluna is its MagTraB (magnetic transducer button) switching, which provides silent switching by using a combination of a footswitch with an integrated magnet and a sensor that is mounted to the circuit board.

When the footswitch is pressed, the sensor measures a change in the magnetic strength and sends this info via microcontroller to a relay with gold-plated contacts that provides the true-bypass switching.

The unit looks nice with its metallic-gold aluminum enclosure (which measures roughly 4.5 by 3.5 inches), black retro-style knobs, and slots for venting heat from the tube. 

The workmanship is top notch. After opening the case I was able to easily get the magnet/sensor back into spec, and the bypass switching functioned perfectly.

Tested with a Les Paul Historic ’59, a Fender American Pro II Strat, and a Reverend Greg Koch Gristlemaster (all through a Fender Deluxe Reverb and a Mesa/Boogie Mark Five: 25 1x10 combo), the Kaluna delivered a satisfying range of warm distortion tones that were easily dialed in with the active EQ controls.

These knobs allow for everything from grinding rock tones (with the middle control around halfway and the treble adjusted to get creamy tones with single-coils or humbuckers) to bottom-heavy scooped sounds with drive, bass, and treble cranked up and the middle knob close to zero.

The Kaluna’s gain is similar to a Tube Screamer’s, and it has a ton of output, so it’s great for those who like to get blues tones SRV-style, by overdriving the front end of an amp while keeping the drive on the low side.

Conversely, a higher-drive/lower-volume configuration allows for easy control of rhythm and lead tones.

Vahlbruch explained that in order for the system to operate properly, the tip of the magnetic switch needs to be 2mm to 3mm away from the sensor when the foot switch is fully depressed.

If this distance changes for any reason – such as might occur if the pedal took a hard knock – the sensor has to be re-adjusted by bending its wire “legs” into the correct position.

This is a fantastic sounding versatile overdrive, which of course comes with Vahlbruch’s proprietary soft-touch and durable MagTraß Footswitch.

Controls - Drive, Structure : V1 (Original / Stock) / Hot (Higher Gain) / Low (Lower Gain), Volume, Active Bass ±12dB, Active Middle ±12dB, Active Treble ±12dB, Power Up : Default On / True Bypass.

The Kaluna II High Voltage Overdrive is available to order from the Vahlbruch Effects Webstore and at selected international dealers - where it goes for €339 / $372 / £282 and equivalent.