AD-3208 build report

[gtrmac]

Well I guess this one was a bit of a disappointment. Probably more so since I already had made a PT-80. The AD-3208's limited delay time does not seem offset by much analog mojo if at all. Actually it doesn't go much beyond a slap-back type echo. I would say that the PT-80 is pretty much all anyone would need and I wish I had known. I would've just made a second PT-80.

But anyway, thanks to Steve Swartz for the effort. The design works! And another thanks for the PT-80. Also thanks to JD for the PCB and documentation. The build was very straightforward and without any problems.

[george]

?what sort of BBD's did you use?  

I used a BL3208 and an MN3205 (I've since ordered a 2nd Mn3205 from Small Bear to so I can get an EMM length delay chain ....  :twisted: )

I was a bit perplexed by the slapback echo on mine until I realised I had used a 50K pot instead of a 500K pot for the delay control ...

Also you can tweak the 1M pot on the clock chip to get a longer delay (within limits, if it's too long the delay quality suffers and you get clock whine coming through with the repeats) ...

I also like the delay level and repeats mods that Scott Schwartz mentions on the bulid notes on JD's website

[gtrmac]

I used 2 BL-3208's.

I was a bit perplexed by the slapback echo on mine until I realised I had used a 50K pot instead of a 500K pot for the delay control ...

Maybe I should double check the pot wiring.

[george]

maybe also check the trimpot that affects max delay time (near the upper LH corner of the PCB make sure it's 1M) and the other components in the RC network that affects clockspeed.

According to Scott Swartz's notes you should get about 200ms with the chips you are using - you can get longer delays by tweaking the trimpot but I find they get a bit grainy.

With mine I can certainly get  more delay than my Boss DM-2