Anyone know any mods for a boss ds-2 dist ?

[jimbob]

[Ansil]

doy ou have a scheme. i could make some mods i just don't have access to the schematic.

[petemoore]

+ or - a diode or two, try different types and configurations.
 See "Simple Mods" on the page bofore the forum index

[drew]

I would throw it out and build a fuzz face...

Seriously though, Boss pedals are a pain in the butt to mod. Little tiny traces with everything PACKED into a box with absolutely no room. Boss "Distortion" pedals are pretty generic sounding, you would probably have more luck with building something that sounds different/better from the ground up. (fuzz face, big muff are my suggestions)

[jimbob]

I agree w the last posting..Im starting to enjoy the sound of boutique and hand made pedals better..I think ill sell it and use the money for parts to build a tube screamer :twisted: !!

[Ansil]

you can build a tube screamer out of a handfull of caps a couple of pots and a lm386.  makes an interesting screamer

[Mark Hammer]

The DS-2 is something I'm not familiar with by ear, but I'm looking at the schem right now (forget where it was posted, maybe at JD Sleep's site from  Kate Ebneter's collection).

It's an interesting circuit, as are most that are entirely discrete (no chips anywhere).

I'm not sure what you mean by "mods".  That could mean "make it do something weird and totally different", "make it sound more like pedal X", "make this feature behave in a more manageable way", "extend the range of this function", or a whole host of other things.  

There are two things readily apparent that entice the tinkerer in me.  One is in the circuit fragment connected to the Distortion control, and looks very much like the base-collector aspect of a Big Muff.  Just like the Big Muff's clipping stages, the DS-2 has a resistance (in this case the distortion control), a capacitor, and a diode/cap combo in parallel in what appears to be the analogous loop.  In series with the diode/cap combo is resistor R56, a 1M resistor.  It is, in turn, in parallel with a FET, Q20, which either allows R56 to function at its full value or else shunts it so that there is maybe a couple of hundred ohms in series with C34 and D8/D9.  In the Big Muff, there is no resistance in series with the equivalent cap and diodes, so I'm thinking that the "Turbo" switch essentially brings the clipping diode pair into the circuit by effectively dropping the series resistance ahead of that cap.

So, what does this mean for you?  Well, in the Big Muff some folks have found that playing around with the value of that cap can produce pleasing and noticeable changes in the tone.  Never tried it myself but theory suggests it could do so.  In the DS-2, that cap (C34) is 2200pf.  In the tradition of the BMP, consider increasing it to .01uf just for the hell of it.  The other thing is that the clipping quality can also be altered by changing the diode complement, generally by sticking in either different diodes or more diodes.  For instance replacing either D8, D9, D11, or D12 with a red LED (making sure to observe the same polarity, and doing just one of each diode pair), will likely produce a hotter output and perhaps a little more growl rather than sizzle.  Alternatively, you could replace any one of those individual diodes with a pair of end to end silicon diodes (1N914, 1N4148) going in the same direction, or a silicon/germanium combo off the same format.

A second general area for modding in a manner that creates big changes with minimal investment is likely the EQ section.  The DS-2 uses what seems to be a fairly common treble boost-cut circuit, whose turnover frequency is set by what looks like C37 (the 6800pf cap tied to the wiper of the tone control).  Swap that cap for something of a larger value (8200pf/.0082 to maybe .012 or.015uf) and the turnover frequency will drop proportionately.  Make it smaller (.0056 to maybe .0033) and the turnover frequency will move upwards.  Having a higher turnover frequency will mean that when you turn the tone down, it will round off the edges but leave more mid-bite, and turning it up will simply change the higher extremes but not affect the mids.  Having a lower turnover frequency will mean that when you boost you will increase the mids a lot more in addition to the highe end, and when you turn down the sound will get much darker than it does now.

So, if it were me, I'd keep the pedal, and try some of these mods.  I think there is some promise there.  They can be done as simple changes on the board, or if you have the room and the chops, you might install a tiny toggle to switch one of these functions.

[jimbob]

Mark, very impressive. I plan to play w it now and try some of the different things..One of the things i was wanting to do was give it more mids.Otherwise, im going to see what i can do based on your ideas. Thanks jim...

[petemoore]

The use of EQ with or without Fuzz [like 7band guitar EQ] has substantial benifits when trying to achieve tone shaping.
 from what I found:
 before the dist unit, and EQ can fairly radically change the sound and intensity of the Dist
 After the dist unit in EQ provides a different tone shaping properties AND can also provide Large Boost.

[jimbob]

Mark--I performed some of the mods..Very cool!!! NO, i mean VERY VERY COOL!! I put sockets in so i can swap out the leds and caps..Lotsa fun!! Just making sure of 1 thing though..I have a wire that worked itself loose from somewhere. I think its from the input jack but not sure..Its # 18 wire on the board near the dc jack? Any help there? If not I understand..You really did me a huge favor on looking at the schematics and offering your thoughts and ideas. Most appreciative!!

[otokomae]

OK, I've read everything I could find in here so far about the DS-2, and have modded the crap out of it till it sounds pretty much just like I want it o in regular mode.  But......  what's with the "TURBO" mode?  It just sounds so weird!  I know that "weird" doesn't really tell you much, but does anyone know what it's supposed to do?  And more importantly, does anyone have any ideas for fixing it?  I was thinking about changing one of the resistors to a Germanium type so that when the TURBO on it gets grittier than before.  Looks like R23-R31.  Not really sure where to start here, though, or even if this is a good idea or not.  I guess the real problem is the tone in TURBO mode.  In NORMAL mode the pedal is actually starting to sound like a Marshall w/ the tone knob @ around 2-3 o'clock, and more like a Mesa Boogie w/ the tone at around 10 o'clock.  The tone knob makes a big difference now.  But when the TURBO mode is on, the sound gets tinny, high-pitched and the gain seems to go up alittle or something making the overall sound kind of weak, especially compared w/ the Normal mode.  

Does anyone have any suggestions?  I'd really appreciate any help as to where to start here, and any ideas about which parts in TURBO mode affect which sounds.  Thanks!!!!

Oh, here's the schematic:  http://www.mif.pg.gda.pl/homepages/tom/files/DS-2.gif

[Branimir]

I am very sorry for getting this thread on the page one again after a year and more, but i didn't felt like opening a new thread just for the sake of commenting mods to DS-2, and to help fellow forumist in searching for DS-2 mod related stuff...

So, here it goes:

DS-2 was my long time companion in music, 6 years now, and my sound changed alot through years, and DS-2 always managed to get that kind of tone out of it, but recently i wanted something more aggressive and wild, so i couldn't resist in opening my sweet little orange box...

The first thing I noticed was the two diodes in antiparallel, D14 and D15 (schem avalaible throught the link in the post before this one).
I replaced them with two 3mm red led's, and tried it.
Results: more volume, the tone is not so smoothly compressed, it's more dirty this way, lower end is well thumped and playing simple powerchords does sound much much more powerfull than before. The tone definition isn't so good, it's now all growl, fuzzed out, bassed out tone, and one should be very careful with this, since I adore this dirty tone, but I don't think it qualifies as a "nice" distortion, think more of a wall of thundering distortion with barely noticible chord changes, of course, you can hear the changes, but it's all drowned up in dirt...

I don't think i'll try to mod more, i could change the second diode pair, the D11 and D12, but i'm afraid I'll alter the mojo sound I get with this thing now...

Coupling caps could be enlarged for more bass, but i honestly think that there's no real need for that now (with led's in...)

Cheers!

[Branimir]

Back from the page 100

Addition:

I tried swapping the D9 an D8 diodes with leds. So its leds instead of D14, D15 and already mentioned D9 and D8.
Results: more output with first pair of diodes was already noticable, and the pedal had more growl. With all four diodes changed, the growl dissapeard and turned into more compressed distortion, probably striking into MT-2 territory, so best suitable for metal i guess, i didnt like it (my personal taste), but i see it could be useful for somebody else.

I put stock diodes from the position of D8 and D9 to the D14 and D15 position, while leaving the two leds in the D8 and D9 spots. I noticed a bit of a change since the first mod, its growly again but there could be differences, i like it this way.

These days im going to try to change some caps, the tonestack one and the to the D8, D9 diodes...

The pedal has now a somewhat different character and Im not trying to immitate or get something XY out of, Im just playing with it to get something i would like to use for my guitar playing...

And there is something i don't like with this pedal... Lacks distortion, correct me if I'm mistaken, but isn't this a discreet way of making an opamp  (the red block)? Therefor increasing the total resistance of the clipping circuit would increase gain? Like having a 500k pot instead of the 250k? Of course thats not possible since the stock pot is small and i dont have one like that... but putting some resistors in series or increasing the value of R55 (the purple block)?



Q16 and Q19 are connected into a differental amplifier for sure. As far as my knowledge (and google) goes: "A differential amplifier is a type of an electronic amplifier that multiplies the difference between two inputs by some constant factor (the differential gain). A differential amplifier is the input stage of operational amplifiers, or op-amps, and emitter coupled logic gates."

But if I figuered mr. Hammer correctly the D9 and D8 pair aren't active until the "turbo" mode is engaged?

There are two things readily apparent that entice the tinkerer in me.  One is in the circuit fragment connected to the Distortion control, and looks very much like the base-collector aspect of a Big Muff.  Just like the Big Muff's clipping stages, the DS-2 has a resistance (in this case the distortion control), a capacitor, and a diode/cap combo in parallel in what appears to be the analogous loop.  In series with the diode/cap combo is resistor R56, a 1M resistor.  It is, in turn, in parallel with a FET, Q20, which either allows R56 to function at its full value or else shunts it so that there is maybe a couple of hundred ohms in series with C34 and D8/D9.  In the Big Muff, there is no resistance in series with the equivalent cap and diodes, so I'm thinking that the "Turbo" switch essentially brings the clipping diode pair into the circuit by effectively dropping the series resistance ahead of that cap.

I'm assuming that the antiparallel pair of D8 and D9 diodes are always active since i noticed sound and volume-wise change after swapping the stock diodes for led's.
Looking at the schematic, i see that the "turbo" switch controls operation of Q14 and Q15 as well as Q20(the blue blocks), and there lies that sound change in the circuit? Mid boost or whatever we call it...

This is a wild guess, but let me try:

While turbo mode active, the R56 is shunted as mentioned, so there is very small resistance (couple of hundereds of ohms), assuming that the total resistance of the circuit here  affects gain, this would mean, less gain. But in this case, the signal coming from the Q22 is bypassing the Q23 network, but i have not figuered what that part of the circuit actually do, but as far as my transistor knowledge goes, it's just a collector follower...

ps: C41 (green circle) could be changed to a higher value to allow more bass frequencies to pass freely, altough it could result in muddy or musshy sound... We shall see...

[Branimir]

C41 changed to 47nF... I guess there's more low end, not much, but my guitar (seymour duncan JB in bridge) is not a low end monster (i tune to dropped C#), nevermind, i changed the R55 to 100k, and there's not much more gain, maybe a little, but i wouldn't qualify it as a usable mod. Maybe 1M instead, dunno, i'll try that later... If it sound bad, I'll go back to 1k...

I'm leaving home in couple of hours so i'll grab SM57 at work tonight and record some stuff tommorow, and i'll put the soundclips here of course...

Just for low end sake i'll replace the C45 with 47nF too...

Pedal sound excellent this way, but I'm curious what else can i get from it heheh

Wish i had germanium diodes to try them in...

edit: C34 is now 10nF, the sound is more focused, less high frequency harshness but middle stays sharp and gritty... Tried the neck and middle pickup and with all the mods already done, there is tons of low end, probably unusable in live situation with bass guitar in the band , but that's why there's bass control on the amp...

I perfer tone in the 12 o'clock position, gain all the way, and volume at 3 o'clock just be slightly louder than with the effect bypassed.

Enough of babbleing from me, soundclips tommorow!

[WGTP]

With the multiple clipping stages being used raising the clipping threshold by changing the diodes provides a greater opportunity for other things in the circuit to distort.  I'm not sure if the discrete Jfet op amps get into the act or not.  Check out the Boss Rod 10.  It has a variety of discrete op amp distortions set up in it.  Also the BD-2, Blues Driver and OD-3 Overdrive.   

[jeroen_verbeeck]

The Jfet's are deffinately distorting, because if you take all the clipping diodes out, you still have distortion.

The function of D14-15 is pretty unclear to me, they don't add clipping nor affect the volume or tone, so I just keep them in.
D11-12 have the biggest effect on the distortion, you really hear the difference when you use a LED or silicon/germanium diode here.
D8-9 have the least effect, I mean, you do hear the difference, but it doesn't really change the overall tone, the effect blends in with D11-12.

I use a Germanium in D8, D9 is standard, D11 standard and D12 a 5mm red Led. This gives me an awesome cruchy distortion, and with the neck pickup and dist to full even fuzzy disortion, it's really cool.
But the best thing is when you totally turn down the dist and volume way up, it makes my amp sound like it's on volume 10 except it's on 2.
It really simulates a driven amp well (in my case).
I'm gonna buy a condenser mic next week so expect some clips really soon.

I took some time to take appart the tonesection, and found out that it does a lot more than only cutting or boosting trebble.
R45: (4.7K) The lower you go, the more bass it cuts in total. You can't go further than bypassing it.
R46: (33K) The higher you go, the more thump you get when the gain is at 2'o clock. So if you like medium gain, make this 100K or something in that area.
R58: (15K) The higher you go, the more upper bass you get, but you lose a fair bit of volume this way. Leaving it standard prooved to sound the best.
R59: (1K) This is the b*tch. The higher you go, the less blistering the trebble gets. I needed to take this part out to satisfy my needs.
You can also put a cap parallel to R46 to be able to cut more, something like 3.3nF has a pretty good result.

I'm gonna try raising C34 like Branimir said, that part made me curious.
R32 is responsible for the midscoop in this pedal. I'm gonna try something lower than 1M to make it sound less scooped. It will probably result in a little more ouput too.
R62 can suposedly be lowered to have more volume, I need to check this.
R57 can suposedly be altered to change the compressed feeling, but it will also affect the bass, I need to check this too.

You may be wondering why I fiddle with the tone control. Well, my amp is pretty bright, and I love it, but with the dist on, it gets over the top bright, and turning the toneknob down is not enough. I also didn't wan't to compromise my bright clean sound.


Question: if I want to change the led into a bright led, then what would I need to change to make it work ?

[WGTP]

This may have been mentioned, but doubling C33 will increase the gain and bass.   

[batpuppy]

@jeroen

Thanks for the heads up. I did one mod (5mm LED on D12) and left it there. So pleased with the tone, now. I may sell my OD-3 now. great stuff!  Best wishes, battus.

[jkokura]

Holy resurrection Batman!












This was from 2003! Brought to life again every couple years, and the last time was more than 4 YEARS Ago! Incredible.

Jacob

[batpuppy]

@jkokura

Yeah, I'm abit embarrassed about it.  But the mod was so good, I felt i had to thank them.  

Cheers for the giggle, Jacob.

Battus