The Tone King Imperial Tri Tube Preamp is a valve-powered preamp pedal: a tube amp preamp stage in a pedal-sized box, with three 12AX7 valves, two independent channels, and foot-switchable reverb and tremolo1. It is claimed to feature the exact same preamp and phase inverter topology as Tone King's Imperial MK II amplifier, its namesake1. Guitar World's reviewer, Connor Flys, describes the Rhythm channel as delivering a "rich, blackface Fender-esque clean sound," with the Lead channel starting from the classic Tweed Deluxe1.
Power and connections
The pedal runs on 12V DC and draws 800mA1. That current draw means it needs a power supply capable of delivering it, rather than a low-output supply shared with other pedals.
At 12V DC and 800mA, the Imperial Tri Tube Preamp draws more current than most multi-output pedalboard supplies deliver per output. Plan its power separately from the rest of a board.
Connectivity is extensive for a preamp pedal. There are eight 1/4-inch sockets: Input, To Amp In, From Amp Send, To Amp Return, headphone out, FX loop Send, and FX loop left and right Returns1. Alongside those sit two balanced XLR outputs, Balanced Out left and right, with a Ground Lift switch, plus a MIDI input, a USB input, and the power socket1. The USB connection links to a proprietary editing app designed by Synergy1.
Controls and footswitches
The Rhythm channel carries Attenuation, a 3-way Cab simulation selector, Bass, Treble, and Volume. The Attenuation knob acts as a master volume that balances with Volume for drive and volume1.
Three dual-function footswitches handle the front-panel switching1:
- Tremolo/Reverb dual-function footswitch
- Channel/Loop Bypass dual-function footswitch
- Bypass/IR Bypass dual-function footswitch
Holding down the latter two also stores presets, up to a maximum of 128, fully controllable via MIDI1.
Reverb and tremolo
The built-in reverb and tremolo are stereo, and the pedal takes pedals in its own stereo effects loop1. The effects themselves are digital, while the preamp section is tube-powered: as Guitar World puts it, "To be able to fit them in at all, these effects are digital"1. Players who want their time-based effects in the analog domain can instead run external pedals through the stereo loop.
What reviewers said
Guitar World's review credits the pedal with "Incredible flexibility and connectivity" among its positives1. The reviewer's account of the sound places the Rhythm channel firmly in blackface Fender clean territory and the Lead channel's starting point at the classic Tweed Deluxe1.
"I'm instantly met with a rich, blackface Fender-esque clean sound on the Rhythm channel."
For players considering other tube preamp options, Tone King also makes the Tone King Royalist Preamp and the Tone King Royalist Tube Preamp Pedal, and the Imperial Tri Tube Preamp sits in the wider field of preamp pedals.
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Questions
How many tubes does the Tone King Imperial Tri Tube Preamp have?
It packs in three 12AX7 valves, which power the preamp itself. The pedal has two independent channels, and the reverb and tremolo are foot-switchable alongside them. Guitar World's reviewer, Connor Flys, describes it as a valve-powered preamp pedal in a box about the same size as a Strymon BigSky.
Are the reverb and tremolo analog or digital?
The reverb and tremolo effects are digital, while the preamp section is tube-powered. Guitar World notes that the effects were made digital in order to fit them into the pedal at all, so the valves handle the amp-style gain and tone stages rather than the time-based effects.
How many presets does the Tone King Imperial Tri Tube Preamp store?
It stores up to a maximum of 128 presets, and they are fully controllable via MIDI. Presets are stored by holding down two of the footswitches, and the pedal also has a dedicated MIDI input plus USB for linking to a proprietary editing app designed by Synergy.
Does it have a headphone output?
Yes. Among its eight 1/4-inch sockets are a headphone out, along with Input, To Amp In, From Amp Send, To Amp Return, FX loop Send, and FX loop left and right Returns. It also carries two balanced XLR outputs, left and right, with a Ground Lift switch.
How much does the Tone King Imperial Tri Tube Preamp cost?
The list price is $599 in the United States, as given in Guitar World's 2026 review. The same review lists £599 in the UK and €699 in the EU.
Is it based on the Imperial MK II amp?
It is claimed that the pedal features the exact same preamp and phase inverter topology as its amplifier namesake, the Imperial MK II. Guitar World's reviewer found a rich, blackface Fender-esque clean sound on the Rhythm channel, with the Lead channel starting from the classic Tweed Deluxe.
Sources (1)
- Tone King Imperial Tri Tube Preamp review, Guitar World, 2025-07-02
