Dude

Portable 5-Channel Audio Mixer (black version)

The Dude has the option of running on four AA batteries or an external power supply, and it's almost as small as its battery pack, making it easy to fit inside a pocket. The mixer is monophonic, but it can drive your headphones, making it the best choice for small portable rigs or sub-mixes on stage.

Its mini-jack input and output offer the ability to mix 5 audio channels. Each channel has a dedicated mute button and up to +20dB gain to boost weak signals and saturate line-level signals.

Unleash the feedback beast
Because each channel provides enough gain, the Dude can also be transformed from an audio mixer into a tone generator by feeding the output back to the input through a passive EQ and other simple circuits. You can finally get that valuable feedback you've been yearning for!

Features
5 channel monophonic mixer
up to +20dB (10x) gain knob for each channel
dedicated mute button switch per channel (not click less)
dual mono output for driving headphones

Technical details
dimensions: 75 x 70 x 45 mm
powered by 4x AA battery or external adaptor 9-12VDC

https://bastl-instruments.com/instruments/dude