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DIY Stompboxes => Building your own stompbox => Topic started by: smoguzbenjamin on June 12, 2004, 05:27:34 AM

Title: Help neede making Boss DD-2 more analog-sounding
Post by: smoguzbenjamin on June 12, 2004, 05:27:34 AM
Hey all

Here's me on a rainy day trying to make my boss DD-2 sound more analog. I looked at the schematic and it looks to me like a cap across the effect level pot would do the trick, only, it doesn't. I tried everything from 6pF to 1uF and it just ain't sounding different, it only gives less repeats, that's all. I know that some people here have modified dd-6's like this so why aint my attempts working :x

Any suggestions as to what I'm doing wrong?
cheers
Ben
Title: Help neede making Boss DD-2 more analog-sounding
Post by: Maneco on June 12, 2004, 02:24:57 PM
Hi,
if you have the schematic of the dm2-3,you'll see that the filters and compander topology are similar...i would suggest replacing the caps around the transistors that form the anti alias filtering stages in the dd2,with the values from those of the dm2...you'll be surprised how close you'll get to analog sound... :D  but i don´t want to start a digital vs analog controversy,so i won´t reply again...
Title: Help neede making Boss DD-2 more analog-sounding
Post by: Prive on June 13, 2004, 03:32:21 PM
I think Maneco is the guy to ask for it!!!!!

Maybe we can start a great mod for this popular pedals, i have both DD2 and DD3 to work on. I havem0t the schems, if you can send it to me we can see the changes to make.

prive@tutopia.com

Saludos, Marcelo.
Title: Help neede making Boss DD-2 more analog-sounding
Post by: smoguzbenjamin on June 13, 2004, 03:54:37 PM
Here's a link for the DD-2 schemmo:

http://www.8bitsindgenug.net/boss_dd2.png

I was sortof looking for a switchable mod (ala Analog Mike) for stock - moderate - extreme modification. Something like that. So far all I've been able to do is reduce the repeats... Is there something I'm missing here?
Title: Help neede making Boss DD-2 more analog-sounding
Post by: cd on June 13, 2004, 04:20:57 PM
Where are you putting the cap on the E.Level knob, from point 3 to 1 or 2 to 1?
Title: Help neede making Boss DD-2 more analog-sounding
Post by: smoguzbenjamin on June 13, 2004, 04:25:42 PM
3 to 1 to pass the highs to ground... is that what I'm doing wrong?
Title: Help neede making Boss DD-2 more analog-sounding
Post by: cd on June 13, 2004, 04:34:58 PM
Yup, try putting a cap to ground in the feedback loop, at the junction of R33 (47k) and R31 (22k), that should kill highs with increasing repeats (repeats get darker).  Or dink with the value of C25, that network forms a low pass filter - start with 0.047uf and work up/down from there.
Title: Help neede making Boss DD-2 more analog-sounding
Post by: cd on June 13, 2004, 04:43:59 PM
Oh  yeah if you want to figure out the low pass frequency (i.e. frequency at which highs start to get cut) use the formula:

1/2piRC, where pi=3.14, R = value of resistor (in M ohms), C = value of cap (in uf).  Stock, highs get cut at around 1200Hz.
Title: Help neede making Boss DD-2 more analog-sounding
Post by: smoguzbenjamin on June 13, 2004, 05:08:57 PM
Cheers, I'll try that out when I finish my spring reverb :)