Search for "Self-made booster preamp test" I plan to stop production of this unit for now, with the three units currently listed for sale. Power supply: DC 9V center negative (Battery operation not possible) I will include the green switch hat in the second image for free. I made this unit by gathering information available online and imagining a certain booster preamp. For the base signal line, I used vintage-leaning parts and parts also used by the original as much as possible, and for the power supply, I used high-precision parts instead of using old parts carelessly. The pots are high-quality Tokyo Cosmos RV24 series. The circuit board is fixed with sponge double-sided tape, and I also considered robustness, such as crimping and soldering the jack parts. Paint) The paint is a high-durability lacquer paint finished in matte black (sanded → primer → lacquer color). I have followed the minimum steps for lacquer painting on aluminum, but the paint may chip upon impact with hard objects. ↓Personal impressions) After watching the test play videos of a certain bassist many times, I was personally satisfied with the result, such as the slight increase in high frequencies when turned on before distortion, the slight increase in distortion amount due to the increase in input gain, and the sound becoming crisp and hard, making the slap sound more vibrant. It seems that the guitarist of the bassist's band also uses it, and as a result of testing it, the cutting sound became more prominent. Depending on the settings, there was also a metallic sound and a natural compression feel. Power-on and sound output have been confirmed. I have selected "New, Unused" for the condition, but I have selected this based on the criterion that it has not been used after production. Please understand that this is amateur-made, and there is no evidence that the circuit used is equivalent to the original. I am careful with thorough inspection and packaging, but please understand that all dimensions and the confirmation of dirt are based on my amateur eyes, so there may be errors or oversight of dirt. 40000pre Susfor