Boss DD-3 Mods

[nephsuperman]

I have a boss dd-3 that I would like to have a more analog sound.  I've searched for mods but all I could find was places to send it off to.  I would rather do it myself and save a couple bucks in the process.  Does anyone know how to make this thing sound analog? 

[dano12]

Talk about timing! I had my DD-3 on the bench last night for the same reason.

Here's a couple of really easy mods.

High-cut mod: add a smallish value cap (I used a 68nf film) from the wiper of the effect level pot to ground. This essentially creates a low-pass filter that cuts the high-end off the delay signal.

Tape echo mod: do the same as above, but between the wiper of the feedback pot to ground. This cuts the highs off each generation of the delayed signal until it decays off to a very lo-fi signal. This mod is REALLY fun.

I'm re-housing my DD-3 to incorporate both mods. Each on will be on a SPST switch to a linear pot so I can control the amount of high frequency content that gets dumped.

Good luck!

[tommy.genes]

Here's an old thread where I talked about the feedback FX loop mod and the feedback hi cut mod. Similar to what dano12 is saying, but you can see what values I tried/used etc. Note that putting the cap across pins 1 and 3 has the same effect as placing one between pin 2 (wiper) and ground.

http://www.diystompboxes.com/smfforum/index.php?topic=42738.msg309116#msg309116

Strange, I tried a search for "DD-3" and only turned up posts from 2007, nothing older than that. Is the search function on the fritz, perhaps?

-- T. G. --

[Mark Hammer]

I have a boss dd-3 that I would like to have a more analog sound.  I've searched for mods but all I could find was places to send it off to.  I would rather do it myself and save a couple bucks in the process.  Does anyone know how to make this thing sound analog? 

There ARE other differences, but what people refer to as "sounding analog" has to do with the additional filtering that analog delays were forced to include in order to keep out the highpitched whine of the clock from the audio signal.  Digital delays were born out of a mindset that valued maximum bandwidth whenever it could be achieved, and since digital technology permitted it to be achieved, that's what we got.  In the real world, reflected sound lacks the bandwidth of the original, so people generally prefer the tone of analog delays chiefly because the direct sound has noticeably greater bandwidth than the delay sound, making it sound more "realistic".

The mods that Dano12 describes are exactly what you should do.  Note that when the cap to ground is connected to the wiper of the pot (whetehr regen level or delay level), the treble-reducing effect is interactive.  As you turn the level pot up, the treble reduction effect is itself reduced.  If you want the effect to be constant, regardless of level setting, the cap goes between the two outside lugs of the pot (input and ground).

The nice thing about the cap on the repeat/regen pot is that it only rolls off a little bit of treble each time, making it possible to have an echo that gets duller with each repeat.  This, in fact, what happens in nature (well, assuming you aren't in a room of glass or polished marble walls).  I've been doing this mod since the early 1980,s and can highly recommend it, both for analog as well as digital units.

[Processaurus]

Good suggestions about internally filtering the repeats, but like tommy was saying you can totally open up a whole range of analogesque sounds by setting up an external feedback loop, I've been having a ton of fun with my modded DD-2 (which is a version of the DD-3), with a graphic eq or filter of some type in the loop (wah is crazy), you can go further than analog at creating an echo that changes/degrades rapidly as it decays, which an appealing kind of production,  getting an idea of what characteristic sounds distinctive about a classic sound and pushing it further than it was originally.

I used a certain low profile jack to be able to use normal mono cords, and get out of the less than ideal stereo trs insert arrangement.
http://www.diystompboxes.com/smfforum/index.php?topic=54972.msg422610#msg422610

If you're interested I could point out how to do that on a schematic, its pretty straight ahead though.

[remmelt]

I've tried the "tape mod" and to my ears there's not that much difference. Perhaps it's my settings or guitar or setup (or ears) but although I can hear a slight treble roll off, it's not something that would really stand up in a live situation, I think. Fun though!

[dano12]

Good suggestions about internally filtering the repeats, but like tommy was saying you can totally open up a whole range of analogesque sounds by setting up an external feedback loop, I've been having a ton of fun with my modded DD-2 (which is a version of the DD-3), with a graphic eq or filter of some type in the loop (wah is crazy), you can go further than analog at creating an echo that changes/degrades rapidly as it decays, which an appealing kind of production,  getting an idea of what characteristic sounds distinctive about a classic sound and pushing it further than it was originally.

I used a certain low profile jack to be able to use normal mono cords, and get out of the less than ideal stereo trs insert arrangement.
http://www.diystompboxes.com/smfforum/index.php?topic=54972.msg422610#msg422610

If you're interested I could point out how to do that on a schematic, its pretty straight ahead though.

Hey proc, I have the schematic but am having a heck of a time figuring out the wiring for the loop...where did you tap the input and the output? Just on the regen pot?

[tommy.genes]

dano12:
Just cut the wire between node 11 of the volume board and node 11 of the effect board (right after the wiper of the feedback knob) and insert your n/c jack(s) there.

remmelt:
Larger caps mean more dramatic high cut, but it's a trade off in that you get fewer repeats. Also, read Mark's post above about the difference between putting the cap between pins 1 and 3 of the feedback pot versus putting it between pin 2 and ground.

-- T. G. --

[Processaurus]

interesting, the version I tried inserted the send and return (with a normaled jack so the send is going to the return when nothing is plugged into the return) at node 12 from the effect board to volume board, so it's before the top lug of the f.back and effect level knob, because I wanted to effect the first echo as well as each consecutive one, inserting it on node 11 would make it so the first echo is squeaky clean, by getting to the mixer before having to go back through the loop to regenerate (though that could be interesting too).
Schematic for the dd-2 and old dd-3, though I bet the new ones are wired the same in this respect.

[dano12]

interesting, the version I tried inserted the send and return (with a normaled jack so the send is going to the return when nothing is plugged into the return) at node 12 from the effect board to volume board, so it's before the top lug of the f.back and effect level knob, because I wanted to effect the first echo as well as each consecutive one, inserting it on node 11 would make it so the first echo is squeaky clean, by getting to the mixer before having to go back through the loop to regenerate (though that could be interesting too).
Schematic for the dd-2 and old dd-3, though I bet the new ones are wired the same in this respect.

Squeaky-clean first repeat problem is what I found also when I first stuck in the filters. Insert filters at the level pot and you affect each repeat equally. Do it at the regen pot and you affect each successive repeat until the delayed signal gets squashed down into a lofi sound. My current hack-job wiring scheme has a switch/pot/filter cap for each of the insertion points. Makes it very flexible.

[tommy.genes]

Processaurus:

You're right. I hadn't thought of that. With the filter/FX loop at node 12, you will get the effect on the very first repeat plus it will become more pronounced with each repeat.

If you place the filter/FX loop at node 13, you get the effect on the very first repeat, but the level of effect will remain the same (not increasing) on each subsequent repeat.

Next time I reopen my DD-2 I will probably move mine to node 12.

-- T. G. --

[Hambo]

Just out of interest, While you guys are prodding around in there, If anyone notices an easy way to increase the output volume of the repeats. PLEASE let me know! I suppose replacing with a larger value volume pot.. or R16 in the above schematic as a likely candidate?

Thanks!

[Processaurus]

Just out of interest, While you guys are prodding around in there, If anyone notices an easy way to increase the output volume of the repeats. PLEASE let me know! I suppose replacing with a larger value volume pot.. or R16 in the above schematic as a likely candidate?

Thanks!

Looking at the output mixer, which is an inverting summing amplifier, you could get what you want by making the resistor in series with the wet signal smaller to make it louder.  On the DD-2 scheme its r14, making it 10K from the stock 33K would triple the output.

Totally OT, but Melt Banana is coming to Sacramento wednesday, hopefully I'll hear the master of the dd-3 skip...

[kissack101]

Processaurus:

You're right. I hadn't thought of that. With the filter/FX loop at node 12, you will get the effect on the very first repeat plus it will become more pronounced with each repeat.

If you place the filter/FX loop at node 13, you get the effect on the very first repeat, but the level of effect will remain the same (not increasing) on each subsequent repeat.

Next time I reopen my DD-2 I will probably move mine to node 12.

-- T. G. --

I tried to to this with my DD-3 but it hasn't quite worked: there is a wire from '12' on the main board going to the pot board, I tried inserting a stereo jack but couldn't get it to work as an effects loop. When I had a closer look it doesn't appear like the wire is connected to anything on the pot board at all? Have I missed something?

More to the point, if I want an effects loop that re-sends the repeats through the effects loop each time, where do i need insert it? I'm aware this is a 'DIY' forum with the emphasis on 'Y' so I feel bad just 'asking' only theres a little more to the DD3 than your regular fuzz pedal and I don't want to hack it to pieces.

Many thanks,

Adam.

[m_charles]

hi!
would the "tape echo" mod dano suggests be applicable to a DD-6 delay as well???

cool thread...

chuck

[Mark Hammer]

The DD6 is a somewhat different beast, from what I understand.  The DD2/DD3 has more in common with the PT-80 project, where a digital chip replaces the actions of a BBD, and the chip is surrounded by analog support circuitry.

Incidentally, if the "best" hi-cut mod is to go from the wiper to ground, you will note that the linked-to schematic for the DD2 shows the input lugs of the feedback and effect-level pots joined together directly.  This means that any hi-cut cap inserted at the input lug of the one pot provides the identical action for the other pot.

You will also note in that same schematic that R31/C25 provides an emphasis network for high end returning to the compander chip.  If you lift either end of that network, you should notice a reduction in highs.  Alternatively, if you lift the 47k resistor they run in parallel with, you'll get an exceedingly bright-sounding regen signal.  Could be promising.

[Processaurus]

I tried to to this with my DD-3 but it hasn't quite worked: there is a wire from '12' on the main board going to the pot board, I tried inserting a stereo jack but couldn't get it to work as an effects loop. When I had a closer look it doesn't appear like the wire is connected to anything on the pot board at all? Have I missed something?

Hi, I don't have a newer version of the DD-3, so the wire numbers may not match the DD-2/older DD-3s (they went through a number of PCB revisions to be able to make it with cheaper processors and less hand wiring), but you can take a look at the mini board with the pots on it, and see which wire does the same thing as the one marked 12 in the DD2 schematic, look for the wire that goes to the top of the regen and effect level pots, that is the one you want to interrupt on the way to the pot board. 

Your jack should be the stereo type, with a shunt switch on the tip contact, which connects the tip to "something" when nothing is inserted in the jack.  You would wire the shunt  switch lug to the ring lug.  Use the ring lug as the send, and the tip as the return.  That way the send (ring) connects electrically to the return (tip) when nothing is plugged in.   Wiring the jack up, the send should be from the main board, and the return goes to the Pot board.  Once you install the insert loop with your switching stereo jack, you should be able to beep out the path from the board, through the fancy stereo jack you install to make the insert loop, and all the way to the pot board, when nothing is inserted in the insert jack, to make sure it is routed correctly.

That help?

[daver]

hey guys...sorry to bump a somewhat old thread.

I'm am stoked about these mods. I will definitely try some this week. I would also really like to mod my DD-3 so that the direct out jack could be replaced as an expression pedal jack for the delay time. Could someone explain to me how to do this? I would be extra cool if there was a way to do it so i could put a switch on it to make the time knob work for when i don't have an expression pedal...thanks guys...any help is greatly appreciated!

[Cliff Schecht]

Just out of interest, While you guys are prodding around in there, If anyone notices an easy way to increase the output volume of the repeats. PLEASE let me know! I suppose replacing with a larger value volume pot.. or R16 in the above schematic as a likely candidate?

Thanks!

Looking at the output mixer, which is an inverting summing amplifier, you could get what you want by making the resistor in series with the wet signal smaller to make it louder.  On the DD-2 scheme its r14, making it 10K from the stock 33K would triple the output.

Totally OT, but Melt Banana is coming to Sacramento wednesday, hopefully I'll hear the master of the dd-3 skip...

Dude no shit, I love Melt Banana! I saw them recently here in Austin (a few weeks ago) and I must say, aside from being the [loudest[/i] show I've been to (I've been to some loud shows too, Dillenger for one), it was the best show I've seen in a long time. So much energy coming from the band and everybody there was feeling it, I was especially love some of the grooves they whip out. Their guitarist has a very unique and interesting style as well, I believe he plays in some oddball open tuning that I'm yet to figure out. The Lightfoot Labs (http://www.lightfootlabs.com/) Goatkeeper tremolo he was using was probably the coolest effect I've heard in a long time, I want one! I got to check out his pedalboard after the show as well, he has a lot of delays on that damn board (I counted 5 including the Boss RV-5) as well as a Whammy and the Line 6 FM4 (both of which are on my pedalboard ). They were telling everyone that they were from Virginia, that was really funny.

[tommy.genes]

I would also really like to mod my DD-3 so that the direct out jack could be replaced as an expression pedal jack for the delay time. Could someone explain to me how to do this?

Geofex is your friend...

Add an Expression Pedal to any effect!

-- T. G. --