IIRC, I read somewhere on the internet that the original intention was so that these were a simple drop in replacement for an amplifier's spring reverb or other reverb type. So if I ever get into making amplifiers - we likely will be revisiting this again.

The Belton Brick comes in multiple different models based on the length of dwell they provide, and whether or not the dwell is adjustable for each output. All modules are stereo capable. They also come in 2 different mounts. I'm using the BTDR-1 for the older mount that uses 2 screws on each side, and BTDR-2 and BTDR-3 for the more common mounts.

Model	Dwell Length	Adjustable Dwell?	Pedals That Use IT	Pinout
BTDR-1S	2 Sec.	No
BTDR-1M	2.5 Sec.	No
BTDR-1L	2.8 Sec.	No
BTDR-2S	2 Sec.	No
BTDR-2M	2.5 Sec	No
BTDR-2L	2.8 Sec	No
BTDR-3	.5 Sec - 3.2 Sec	No	CreepingNet PsychoVerb CreepingNet CrystalBox Cusack Music Reverb SME Cusak Music Sweetverb

So as you can see, these are basically "reverb on a module" type devices. The earlier units (BTDR-1 and BTDR-2) are designed more to be like a "spring reverb tank" found inside a guitar amplifier. While the BTDR-3 is meant to be a bit more controllable as it adds "dwell length" knobs to the circuit, making it a more ideal device for pedals (usually). It really depends on what you want in a reverb. Since I - for some reason - like to make extremely complicated pedals despite a big lack of understanding in Electronics, I tend to favor the BTDR-3 personally and use it in all of my designs and devices. Right now there are not one, but TWO devices making use of it - one is the reverb-only "DeForestAtion TreeVerb" pedal, which is my first reverb pedal (model# CRV-1), the next one is the CrystalBox (CBX-1), which is intended to emulate the etherial voice guitar sound I used on "Crystal" in Lithium, in 2001 (basically a delay/chorus/reverb combo).

Glue Circuitry - There's two particular "glue circuits" you need to create to make a pedal with this. The first one is a power regulator that steps down the voltage to 5 volts direct current - which both your 9volt battery AND power adapter must pass through. This is because the PT2399 chips used inside the Belton Brick module require a perfect 5vdc power source to work properly, and that's one reason we're not diving directly into working with the PT2399 (which can be used for Delay, Reverb, Chorus, Flanger, and other time based effects), because that chip can be REALLY tempermental.

The second piece is the Input and Output buffers which consist of Op Amps. On all my pedals, I tend to use LM386s on them - because I like how they sound.