BOSS DS-2's TURBO mode: What's it for???

[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 to 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 is on it gets grittier than before. Looks like R23-R31. But I'm 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 a little or something making the overall sound kind of weak and thin, 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

Thanks!!!

[nooneknows]

maybe it could be useful:
http://www.diystompboxes.com/sboxforum/viewtopic.php?t=239&highlight=ds2

BTW I have a DS-2 too but I still haven't found a use for the turbo mode...

[smoguzbenjamin]

I tried a DS-2 and I found the Turbo mode to be some sort of attempt at making the thing sound MetalZone-esque somehow. Here's my verdict: Get a DS-1 AND an MT-2

[Kent S.]

The Turbo mode on the DS-2 is nothing more than a midrange boost after the distortion ... not really useful to me, if it were an overdrive then maybe it would help (if revoiced) to capture a bit  of a tube amp's power stage's bandwidth closing off a bit. Unlike the turbo overdrive it does nothing to boost the gain *into* the distortion circuit,, now if you could find a way to put it *before* the distortion circuit then it would make a more natural sounding gain boost for leads. A lot of people argue that they don't like scooped mids after distortion, however that would have been a bit better in this case, as boosting mids after distortion results in uan unatural sound, before distortion would result in richer harmoincs with more saturation without extra hash and mud. If you can find a way to reverse it's order with the gain into the distortion then you'll have a nice useable boost.

[otokomae]

Hmmmm.....  that's a lot to think about.  I really don't know how to put the TURBO mode before the distortion;  I'm afraid I'm getting in a little over my head.  Really, my best idea so far was just to play around with the cap value of C20, perhaps, but I'm really new at this and still learning how to really understand a schematic.  I've also been told that w/ the DS-2 I picked a really hard pedal to start with, but it's the only one I have (I bought it in Japan, where the DS-2 was actually cheaper than the DS-1 at the time, as DS-1's were discontinued there, or something).  

Anyway, thanks to eveyone who's posted an idea here, as I'm really trying to take all this in, and if anyone has any more good ideas or knowledge of this part of the circuit  please don't hesitate to post it!!!  Thanks!!!

[nooneknows]

DS-1s DISCONTINUED?!?!?
AAAARRRGGHH!!! Come on guys!!! let's catch'em all!!! they'll start going vintage in a while!! :D!!!

[smoguzbenjamin]

No dumb-ass idiot is going to discontinue the DS-1. Come on people are still buying that orange gem. In a while there's gonna be DS-1s for every soul on the planet! :mrgreen:

[otokomae]

Sorry guys, I didn't mean to start a panic! The DS-1 is still being made, as far as I know. What I was talking about earlier was that during the time that I was living in Japan (1999-late 2000), for some reason Boss had taken the DS-1 off the Japanese market, so in Japan you couldn't buy new ones at that time. And you're right, they did somehow become "instantly vintage", and used ones were selling for insane prices in Ishibashi and other places that sell used effects in Tokyo! I think they're back on the market there now, though, as used DS-1 prices seem to be back down to around $50.00 or so, just a little less than a DS-2 or an MT-2  http://www.ishibashi.co.jp/u-box/  (Hit the little box in the upper left corner that says "BOSS" on it to see prices in Japan). Hope I didn't cause too much confusion, and once again, please if anyone has any advice about this DS-2's TURBO mode, I'd greatly appreciate the help! Thanks!!!

[cd]

The DS-1 ain't going anywhere.  It's been selling better than ever since BOSS dropped the price a while ago.

[travissk]

At least here in the USA, the DS-1 and SD-1 Super Overdrive are Boss' entry level pedals designed to get you hooked. You should be able to find both for $40 new, and used prices of $25-32 or so are fairly common.

[otokomae]

ummm...  wow.
Is there anyway we can get off the subject of the DS-1 and get back to the DS-2 that I've been having a problem with?

[donald stringer]

Mark Hammer wrote: [this is his post on your subject and a safe bet that if you can do anything with it this would be a good start.  I also noticed the fets and if you could find out which one effects the distortion the most it it might be interesting to swap one out with a j-fet 201 but I guess that would be a little far fetched but if your a dedicated tinkerer it might be worth a try.]                                                                        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 ......

[RDV]

Kurdt Cobain sure did like that pedal. Seemed to work well for him 'live'.

R.I.P.

RDV

[Kent S.]

I think donald has some good ideas, however if I understood the previous posts it seems that the person is generally happy with the sound of the DS-2 ;it's just that mid-boosted turbo mode that is a pain. Ideally that would work better pre distortion, unfortunately i don't know off hand how you would put it there, I also think that it somehow jumps back to the full 9V of the circuit rather than the 8V (as BOSS has gotten rather found of doing that as some type of regulation/better filtering something or other ... not sure there). If you can trace the signal thru the scheamtic and eliminate the turbo connection when off, then you may be able to find where the turbo section starts and where it ends, and cut a trace or two and reroute it. Sorry no easy answer for you though. DS-1's are a lot easier to mode bTW. Also I thought the DS-2 has a BMP style tone control, like the DS-1 and DF-2? Maybe not, it's been a while since I've seen thise schematic.

[otokomae]

Well, thanks alot to everybody who posted suggetions about the DS-2!  Rerouting it so that the TURBO mode comes in before the distortion does sound like a good idea, but looks extremely hard, so I'm gonna try changing the values of some of the parts to have it scoop mids instead of boost them, and see how that works out.  If I happen to find some magic solution to the TURBO mode problem I'll be sure to post it here for future reference.  Incidentally, does anybody know how the "TURBO" (or whatever) mode on the Ibanez TS9DX pedal works?  (It says it's supposed to add low-end crunch).  Anyway, thanks!!!

[WGTP]

A silly suggestion, but set your amp or get an EQ and set up a notch so that when you hit the Turbo it sounds like it did on the normal setting without the notch.