Hughes & Kettner Switchblade

It used to be that the terms “tube amplifier” and “programmable” were nearly mutually exclusive, and if you wanted a programmable guitar amp, you were probably talking about a modeling guitar amp. So perhaps it’s no wonder that Hughes & Kettner—a company well known for making both tube and digital amps—would come up with the Switchblade, a four-channel, 100-watt tube head that features fully programmable controls and onboard digital effects. Sporting a single set of Gain, Volume, EQ, and effects knobs, the Switchblade can automatically store whatever knob settings you dial in on any selected channel. Set the controls for, say, a crisp rhythm sound with reverb and chorus on the Clean channel, a heavier distorted tone on the Crunch channel, a vicious lead tone with a short delay on the Lead channel, and a hyper-gain sound with reverb and a long delay on the Ultra channel, and you can then toggle between these sculpted sounds just as if the amp had independent controls for each channel
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This type of intelligent operating system—which hasn’t been seen before on a multi-channel tube head—provides maximum control over the channels, while drastically reducing the number of knobs typically required for fully independent control of multiple channels. H&K also reports that the controls are automatically revoiced for each channel’s specific tonal requirements, which is another impressive aspect of the Switchblade’s design.


The Switchblade makes it easy to forget about all the digital stuff when you start playing it. Tested with a variety of humbucker and single-coil guitars, the amp displayed the sonic and dynamic signatures you’d expect from a good multi-channel tube head. You can get everything from pristine clean tones to ridiculously overdriven sounds, and with so much variety between these extremes, it’s hard to imagine not being able to get the sounds you want. The gutsiness of the tones is impressive, and the dynamic response is excellent— even in the most extreme gain settings.

Perhaps due to its soft-clipping rectifier, the Switchblade has just enough “give” to keep it from feeling too mean, yet this beast can rage at ridiculous volumes when you crank up the global Master Volume. This control sounded a little scratchy, however. Another slightly bothersome thing is the way the channel Master doesn’t transition smoothly from zero volume, but jumps to an audible level instantly, as if it were a switch.


These small gripes aside, the Switchblade is a very cool amp with a lot of smart features. Channels can be selected via the four-position rotary switch on the front panel, or the included FSM 432 MIDI board (which must be connected in order to access the 128 user presets). The board is factory configured to keep a selected sound active while you’re scrolling to the next bank of presets, but you can opt to switch to Direct Mode operation, whereby the sounds change immediately to the corresponding preset on the next bank you select. Storing a new sound for board activation is easy. Press the Store button on the amp (it lights up), select a bank destination on the FSM 432 (from 1 to 32), then press the A, B, C, or D button on the board, and the new sound is saved to that bank and preset. (You can also store presets by simply holding the Store button for two seconds, without touching anything on the MIDI board.) Now, 128 memory slots is probably overkill for most players, but it does give you the ability to set up a couple of different sounds for each song in your set. If your needs are more far reaching, the Switchblade’s MIDI In and Thru jacks allow you to control external devices (such as switching patches on an effects processor), or even have the amp’s presets controlled via sequencer commands.


The Switchblade’s digital effects sound quite good, are very quiet, and up to three effects can operate at once. The one-knob reverb was non-functioning on the first Switchblade we tested, but it worked perfectly on the replacement amp. It sounds so spring-like, that we actually had to shake the amp to confirm a spring tank wasn’t hidden inside. The reverb time increases as you turn up the Reverb knob, and high settings produce long tails and enough wetness to cut it for surf.

The 3-knob delay section is suitable for everything from short slapback effects to spacious echoes that can sound quite cavernous when embellished with reverb. And while 1.4 seconds of maximum delay time isn’t much, you can adjust the repeats to go on forever, which allows for some trippy layering effects. You can also perform quick delay-time changes on the fly using the Tap button. It would be nice if you could also adjust modulation rates using this function, but that’s not possible as the delay and modulation effects are always available for simultaneous use.

Chorus, flange, and tremolo are available via the Mod FX knob. This multi-function control also varies the depth and rate as you turn it through the range of each effect. On the chorus setting, for example, the depth is reduced as you turn the knob clockwise, thus keeping the chorus from sounding too warbley at faster rates. Obviously, this system doesn’t give you much control over the effects, but the sounds are pleasing nevertheless. The chorus sounds sweet and rich when deployed at a slow speed on the clean channel, the tremolo offers a great pulsing vibe at medium settings, and the flanger sweeps from classic, jet-like swooshes to textures that veer into the rotary-speaker domain. The only hang is that the Switchblade’s effects are designed to be configured into presets, and they can’t be simply turned on and off via the MIDI board. If you want to be able to bypass the effects remotely, you’ll need to connect an optional H&K

FS-1 (or similar on/off footswitch) to the rear-panel Effects jack. You can also toggle between two amp channels by plugging an FS-1 into the 1/4" jack adjacent to the MIDI ports, or control all four channels using H&K’s four-button FS-4 footswitch. These are good options to have in case the MIDI board develops a problem, or you forget to bring it to the gig.

Switch Cheese

The Switchblade largely succeeds in its goal of melding tough tube tones with the programmability and onboard effects previously available only on modeling amps. Aimed at players who have a “been there, done that” attitude about tube modeling, the Switchblade takes a step backward in the sense that it uses digital technology solely for system control and effects generation, while leaving the heavy lifting part of the tonal equation to the tubes. Thanks to a well-implemented control interface, the Switchblade is user friendly enough for luddites, yet it’s packed with enough presets and MIDI-control possibilities to keep a tech-head grinning. Bottom line: If you’re into exploring the cutting edge of modern amp design, add a Switchblade audition to your list of things to do.