Build Your Own Clone Message Board

A recent addition to the homebrew lineup:


A GGG AD-3208 analog delay. I'm still tweaking the circuit a bit, but it sounds GREAT. The only change I'd make in building it again is to go with a bigger enclosure... it was a PITA to come up with a layout that would work in a 'BB' style enclosure, and there's no room to spare at all. Oh, and the reason the trimpots look all staggered is because they ARE... the board from GGG didn't provide enough room for them to be mounted flush with the board... that was a headache too. At least it worked the first time I fired it up though!

Nice. Did you use MN3208 or 3205 for the BBDs?

_________________
*patience is a virtue*

Please do not PM me. email is prefered. keith@buildyourownclone.com

I used the 3208's in the interest of fidelity on the shorter delay times... and while they're only supposed to produce 200ms of delay time, I've got it set up to produce 250ms or even a little more and I still don't have any clock noise!

I didn't have a scope, so I had to set everything up by ear... it was a little tricky, and I'm sure it'd even sound better with a scope, but I'm impressed with this circuit... rivals the DM-3 I used to own, that's for sure... heck, it even keeps up pretty darn well with the Echoczar at similar shorter settings, and in fact, it's even quieter, but of course it has no where near the headroom of the 'czar.

Cool pedal. Highly recommended build.

I've built that project. It's really just an Ibanez AD80 modified for the MN320X series bbd instead of the MN300X series with 2 cascaded bbds for double the delay time. The AD80 is 18v. If you converted the AD3208 to 18v, you'd probably get as much headroom. Another good mod is to use the 2305's and add a "short/long" switch to bypass the 2nd delay stage for anything less than 300ms. Get a larger enclosure and stick two more delay stages in there for 1.2seconds. Build a second one and then see if you want to keep the echoczar.

_________________
*patience is a virtue*

Please do not PM me. email is prefered. keith@buildyourownclone.com

The problem is I'm an infant when it comes to design... How do I add delay stages? How do I convert to 18v? Maybe there aren't short answers to these questions.... I really don't know! ;)

It's actually quite simple. Delays are not as complicated as people think...they just have a lot of parts.

It will become more appearent if you compare an AD80 schematic with the AD3208. You can see on the AD80 where the MN3101 drives the MN3005 and the signal enters and exits the MN3005 exactly the same way that the MN3102 drives the two MN3208 and the signal enters and exits the MN3208 on the AD3208. The only difference is that pins 1 & 5 are switched on the two different bbd's.

See how the two mn3208's share all the exact same pins accept for the in/out of the signal? The output of the first mn3208 is passed or cascaded to the input of the second mn3208. In theory, you could continue cascading the BBD's in this manner indefinitely for more delay time, but there would inevitable be noise issues and you would definitely need a scope to set it up.

The AD80 uses an 18v supply, but actually runs on 12v. There is a 12v regulator and the reference voltage is 6v as opposed to 9v/4.5v. Converting to 12v would probably be the easier place to start if you were interested in modding your AD3208.

_________________
*patience is a virtue*

Please do not PM me. email is prefered. keith@buildyourownclone.com

Or splitting the BBD's with a toggle switch. THat would actually be pretty easy to do.

_________________
*patience is a virtue*

Please do not PM me. email is prefered. keith@buildyourownclone.com

Guys, can you help me, I saw this and bought all the bits, etched the PCB put it all together, but I can not get it to work.

I've traced the signal to the input of the first BL3208, and thats where it stops. Also there is alot of clock signal appearing, is that normal? I hope you can help, as I have tried replacing the BL3208 and adjusting trim pots - do you have any sugesstions, if you need any schematics give me a shout - cheers, Dan