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Koch Amps Jupiter Junior 20W 1x10 Combo Amplifier

Written by

Elliot Stent

Koch Electronics has been building guitar amplifiers since 1988. With 30 years of experience, the brand has refined its lineup significantly since the early days, now boasting a range of classy boutique-style amps. The Jupiter Junior 20W 1x10 combo is one of their many amazing offerings, a small and portable tube-powered combo that packs a serious punch.

Hybrid Power

Driven by two 12AX7 tubes, split between the power amp and pre-amp sections, the Jupiter Junior is a flexible hybrid amplifier. Using Koch's ATR (Authentic Tube Response) technology, the rest of the solid-state circuit simulates the feel of a full-fledged tube amp.

This means that you can attain that genuine tube sound but at a great, affordable price. And the use of only 2 tubes also minimises the chance of failure, meaning that the Jupiter Junior is a very reliable amp that is ideal for small to medium-sized club gigs with its 20W of power.

3 Channels

Despite its small stature, the Jupiter Junior is crammed full of features. You can easily switch up your sound with its 3 distinct channels - Cool (clean), Hot (overdrive) and Hot Gain Boost.

The Cool channel boasts a bright and chimey clean, with plenty of rounded warmth and a clear upper mid-range. Crank the amplifier and it will break up nicely, offering a snappy bite that's great for pokey blues tones. The Hot channel is a slightly different beast, with a smooth overdrive tone that's perfect for warm lead tones. Turn up the mids and treble, and you'll get a far more punchy sound that's ideal for old-school AC/DC-style riffing!

Activate the Hot Gain Boost, and you'll get an even raunchier drive tone, offering more saturation and hair. With enough gain to get to hard rock levels, this channel can certainly dish the dirt, especially when used in conjunction with humbucker-equipped guitars.

Modern Features

The Jupiter Junior may be easily mistaken as a vintage-inspired amp from its 60s-esque aesthetics, but it also has some cutting-edge features to meet the demands of modern players.

On the rear panel of the amp, you'll find a recording output with a passive speaker emulation filter, giving you a convincing mic'd amp sound. This means that you can quickly record studio-quality audio into an interface, or even send a signal directly to a front-of-house PA system for a bigger live sound.

You'll also come across the amp's buffered serial effects loop at the back of the amp. This can allow you to run you time-based and modulation effects at the optimal operation, with the buffer ensuring that their signal is strong and vibrant. This means that you won't suffer from any tone loss by running multiple pedals through the loop, a premium feature on this modestly-priced amp.  


  • 20W Hybrid ATR amplifier (ATR = Authentic Tube Response)
  • 1x 12AX7 tube in the pre-amp
  • 1x 12AX7 tube in the power amp
  • Three foot-switchable channels: Cool (clean), Hot (overdrive) and Hot Gain Boost
  • Volume control for the Cool channel and separate Gain and Volume controls for the Hot channel
  • Passive Bass-Mid-Treble tone controls for both channels
  • Spring emulated reverb with Volume control
  • Dimmer for continuous control of the output power between 0W and 20W
  • Buffered serial effects loop
  • Recording output with passive speaker emulation filter
  • Speaker on/off switch for silent recording
  • Extension speaker jack
  • 1x 10” Jensen Falcon C10-40 speaker
  • 2-way footswitch not included
  • Dimensions 45(w) x 42 (h) x 23.5 (d) cm
  • Weight ca. 12 kg
Inc. VAT

2 In Stock

Order now for delivery to you on Monday, 6 December 2021  

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