The Koch Jupiter Junior is a 20 Watt boutique, vintage style combo amp based on his bigger brother the "Jupiter 45". 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.

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.

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.