More Distortion on my From-Scratch TS-808/9/10/X

[Deathmagus]

Well...  For my first project, I decided to build a TS-808, based on the schematic from General Guitar Gadgets.  I hooked up with a friend of mine who's into electronics, and went at it.  Before building, however, I also looked at the TS-9 and 10.  Since they are (it would seem) very similar to each other (merely a resistor or two off from each other) I also added in the attributes from those pedals as well, so I can switch between all the models.  This is the Schematic I designed:



Switch 1abc is the thru-pass/LED toggle, and switches 2/3 add the resistors necessary to make it a T9 or T10.  The other switch is simply an on/off switch.  If the switch for T-9 is off, and T-10 is on, I get a previously unused setting, which I call T-X.

The only differences between what I have built and what I designed are (I believe) that the chip isn't actually the JRC (which is being shipped in a week or so), one of the caps (.22 uF?)is actually a little stronger than it should be (but the rating difference is less than 5%, so it's within tolerance range of the "correct" resistor), and I parallelled 3 smaller capaciters to match a cap I didn't have.  The second two changes I think are negligible.

My problem is the level of distortion.  Currently, at maximum drive, level, and tone, I get a very crisp, clean, overdriven tube amp sound.  It sounds quite lovely, actually, but I've heard sound bytes of modded 808s that pack a much harder punch.  My question is what might I have done to have screwed it up.  Am I supposed to be able to get a stronger drive out of just the pedal alone?  Is it all in the JRC op-amp?  How can I get a wider range of sound from my box?

Additionally, I can't notice any difference between the 4 combinations of switch settings (from switches 2 and 3).   I can understand this, since they're all Tubescreamers, but is there a good way to get a little more variety from the different settings, while remaining true to the Tubescreamer sound?

Any suggestions would be appreciated, and I would be happy to answer any questions.

[rockgardenlove]

No clue, but Transmogrifox has a mod that you might want to try...see if that helps.
http://stompboxmods.com/modslist.php?id_pedals=33

[markm]

What about changing clipping Diodes?

[Deathmagus]

The diodes I'm currently using are IN194B's - Does that help?

Also, since I'm not sure that my schematic came through, the one I made can be found at

http://ic1.deviantart.com/fs9/i/2006/145/5/c/ShadowScreamer_Schematic_by_Deathmagus.png

[Deathmagus]

Well, I started fiddling around with it, wiring 2 diodes each instead of one, and when I changed it back, it seemed a lot "crunchier" might have just been a loose connection.

Thanks to all for help!

[bancika]

Try Kelley mod (it's described on his site), it will increase gain range - less gain wit pot turned down and more gain with pot up.

[twabelljr]

     Try Frank Clarke's site. Specifically the Tubescreamer general hotrodding.

http://web.archive.org/web/20020206124650/http://members.home.net/fclarke/fx/

[AL]

GEO FX "Technology of the Tube Screamer" EVERYTHING you could possibly want to know except why a "vintage" TS-808 costs more than a guitar.

AL