This unit is a clone head amplifier created based on the circuit diagram of my Aguilar Tone Hammer 350. While faithfully reproducing the basic circuit, I have added features to make it easier to use. Main Specifications: Input: 1 x Phone Jack Output: 2 x Speaker Outs (Speakon, Phone) 1 x DI Out 1 x Headphone Out *See below Power Amplifier Section: TPA3118 module used, rated at 60W Additional Features: Mode Switch added *See below Size: W150 x H50 x D130 The mode switch adds a filter circuit and Presence, similar to those used in Sansamp and Darkglass, after the first-stage buffer, allowing you to switch between them. Although the original amplifier has a mid-focused sound, turning this switch on allows you to easily create a so-called "scooped" and punchy sound. Presence only functions when the switch is on. Also, the headphone out is branched from before the power amp input, so it is intended to be used as a preamp out in a half-inserted state. It's a size that can fit a 4-inch speaker on top, and I have been using it by connecting it to a powered speaker from here. (Photo 17) Prioritizing miniaturization and simplification, a tuner out and send/return are not implemented. The LEDs for the mode switch and mute switch are white, and the clip indicator is pink. Also, a pink LED is embedded inside the input jack as a power indicator. After power input, an isolated DCDC converter is used for the preamp. The power amplifier passes through a noise filter circuit, but there is a possibility that switching noise that cannot be completely removed may be heard. Thank you for your understanding. Although one preamp is enough for luggage, this might be suitable for those who want enough power to drive a small passive speaker at home. Included are a power adapter and a paper with a simple explanation. (Photo 3) The Aguilar amplifier, batteries, and speakers in photos 14-17 are for size comparison and are not included. This is a handmade item by an amateur, so there may be paint unevenness and scratches from manufacturing. Please refrain from purchasing if you are sensitive to these issues. #BassAmp