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---
title: Stick preamp PCB arrived
tags: audio,pcb,DIY,preamp,chapman stick,free software
---
Today I received a package from Shenzhen containing ten printed circuit boards.
I ordered a single board through [a taobao store](http://taobao.com) for only
100 RMB (about USD 16), but I suppose there is not much of a
difference between the production costs of ten boards and that of one.
The board is the heart of my two-channel Chapman Stick preamp / signal router.
It includes a cross-over circuit for the bass side, so that I can partition the
bass signal into two frequency ranges that can be routed and processed
independently. It has three very simple effect inserts (high bass, low bass,
and melody), two buffered outputs (both signals mixed down to mono or dual
mono), and a tuner output (which could be used for an on-stage monitor).
The circuit and the board were designed using the
[free](http://www.fsf.org/about/what-is-free-software) programs
`gschem` and `pcb` of the excellent
[gEDA suite](http://www.geda-project.org). (For some odd reason `pcb`
is not available through the official Archlinux repositories; I
installed it through the Arch User Repository.) You can get my circuit
diagrams, the PCB layout, and custom footprints through the
[git repository](http://git.elephly.net/hardware/stick-preamp.git) I
set up for this project.
The manufacturer only received the exported Gerber files that I checked with
`gerbv`. Sadly, I didn't realise that the silk screen layer would be printed on
the bottom side of the single-layer board, so the text on all ten boards is
mirrored. (I suppose I could get used to saying "TЯƎƧИI", but "YᗡO⅃ƎM" just
sounds weird.) Now I will have to carefully check the orientation of the
transistors before soldering them onto the board because I'm not sure whether
they have been mirrored when I designed the board.
I'm still missing two or three parts (different component packages and power
line filtering), but I'll start soldering the first components to one of the
boards tonight.
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