Posts Tagged ‘ Accutronics ’

Digital Reverb (Accutronics BTDR-2H)

First of all, let me say this. I love my amp. It has great tone, and breaks up at a friendly volume level. But it lacks one thing that I rely on to cover up my (many) mistakes: Reverb. I didn’t want to just build another pedal. I wanted this project to be a special one. As I keep reverb turned on 85% of the time I thought instead of building a pedal (that would take up valuable board space) why not build a little unit to sit on top of my amp. Influenced by the lovely Fender tube-based spring units that sit on top of your amp I set out to create my own little op amp and digital circuit.

I purchased an Accutronics BTDR-2H digi-log reverb from a friend from over the pond and the rest of the parts from local suppliers. I based my design off a vero layout found at Sabrotone.com. While his design was originally designed for the BTDR-1 Brick, I was able to modify it with help from the brick’s designer, Brian Neunaber. Brian was a fantastic help and answered my E-mail within one hour (very impressive to say the least).  As I was using a DPDT toggle for the switch I used a Millenium 2 bypass wiring to enable the use of an LED.

Accutronics BTDR-2H Vero

Red text shows the correct pinout for the BTDR-2H rever brick.

Since it was going to be sitting on my amp I wanted it to have more of a visual impact and instead of using a small enclosure I decided to go big with a Hammond 1590T die-cast box.  This left me with plenty of workspace and I had no problems fitting all the components nice and neat. Here’s what it looked like when I was just finishing up with the heatshrinking and cable management and such.

You’ll see I used sockets on the reverb module. These bricks come in Short, Medium, and Long decay models. I’m using a Long decay module, as, well, like I said, I like reverb.

Remember when I said I wanted this build to be epic? Well to really test my patience I decided to cover the enclosure with Tweed tolex, much like vintage fender amps. I purchased a small amount of the authentic material (I found out that many of the suppliers online sell a vinyl simulated tweed – Do not want) and began measuring and cutting. I won’t post a tutorial here, but one of the most difficult parts is making sure that thepattern in the corners line up just right. I somewhat suceeded in this, but hey, it was my first try.

After doing a bit of research I decided on coating the tweed with several thin coats of Minwax Polyshades Honey Pine. This is a stain/poly mix that will protect while it stains. I used 4 coats and wetsanded afterwards. I wasn’t too particular about getting exactly even coats as I wanted this reverb to look like it’s been through years of gigs and tours. Here’s the final result. I really should have taken more pictures of the process…

It fits nicely on top of my small 5F1 clone, and sounds beautiful, with no digital artifacts or loss of volume. I was surprised that this quality of sound was available from a small digital circuit with just a few ICs and parts. For anyone looking to build a reverb, those little bricks are highly reccomended.