how can i add a mids control to a tube screamer circuit?

[GibsonGM]

Not many people want to spend 1/2 hour going thru someone else's breadboard work, Snow!   It's hard enough doing your own.   I say make sure your power pins are all going to the right places (they seem to be), and fire it up...there is no substitute for actually building the circuit yourself on BB. 

[snow123]

Not many people want to spend 1/2 hour going thru someone else's breadboard work, Snow!   It's hard enough doing your own.   I say make sure your power pins are all going to the right places (they seem to be), and fire it up...there is no substitute for actually building the circuit yourself on BB.

lol, i just wanted to make sure everything looked right since i was pretty exhausted when i was done making it. and ive missed so many things while doing everything on the fly.

[GibsonGM]

Nothing wrong with that, Snow.  How did you make out?

[snow123]

Nothing wrong with that, Snow.  How did you make out?

ok, i just got everything working, but when for some reason with the volume in between 75 and 100%, the mids control seems to be distorting the signal (almost like a boss ds1) when maxed out. and if it affects anything, im using 2 red leds for the diodes, and for ic1 im using an mc1458, and for ic2 (the mids control) im using an rc4558.

[snow123]

and the bass cut control doesnt seem to do a whole lot in between all the way down and maxed.

[GibsonGM]

For reference, is there a complete and actual schematic you're working from that you can post?

If you increase the mids above what was orig. intended, that in itself may cause distortion depending on what's 'downstream' - could cause a following opamp to distort....and oftentimes, controls are so interactive that a bass cut or something with the mids might seem like it doesn't do much (like, if the mids are down, they may have already taken out the bass, that stuff).    this is why I put a lot of emphasis on "you're SURE you want to redesign the TS??"  lol.    But sometimes we do have to try, I know.

If you can get a schematic to look at, that would help.

[snow123]

For reference, is there a complete and actual schematic you're working from that you can post?

If you increase the mids above what was orig. intended, that in itself may cause distortion depending on what's 'downstream' - could cause a following opamp to distort....and oftentimes, controls are so interactive that a bass cut or something with the mids might seem like it doesn't do much (like, if the mids are down, they may have already taken out the bass, that stuff).    this is why I put a lot of emphasis on "you're SURE you want to redesign the TS??"  lol.    But sometimes we do have to try, I know.

If you can get a schematic to look at, that would help.

here's the schematic:

[iainpunk]

and the bass cut control doesnt seem to do a whole lot

i think its the wrong kind of bass control, i suggested another bass control 

i would put the filter before the gain stage, not in the feedback loop


cheers

that 470n can be bigger, and polarised, with the (+) towards the opamp.
it replaces the bass cut in the feedback loop with a bass cut in front of the clipping amplifier, and changes the frequency of the bass cut, not the depth. this makes the control quite powerful and intuitive.
i recon its fairly easy to try this on the bread board, if you have the components.

cheers

[snow123]

and the bass cut control doesnt seem to do a whole lot

i think its the wrong kind of bass control, i suggested another bass control 

i would put the filter before the gain stage, not in the feedback loop


cheers

that 470n can be bigger, and polarised, with the (+) towards the opamp.
it replaces the bass cut in the feedback loop with a bass cut in front of the clipping amplifier, and changes the frequency of the bass cut, not the depth. this makes the control quite powerful and intuitive.
i recon its fairly easy to try this on the bread board, if you have the components.

cheers

uhhhhh
the control is really messing with the mids lol


the schematic and graph on the left is the stock tube screamer just with different diodes (LEDs) and without the 51pf cap

[snow123]

and the reason the bass cut control feels like its not doing much, is 'cause the low end is like 5db louder than the stock tube screamer. so even when the bass cut control is maxed, everything still feels too bassy.

[GibsonGM]

Well Snow, Iain suggested another way to do it - have you tried that?  This was about giving you more control of your MIDS when it started, remember?     If I was going to re-do the whole tone shaping setup of the TS, I doubt I'd do it this way.    If that was the case, I think I might go for a flat mids mod (AMZ etc), and then start from there.  It's really just a soft-clipping opamp with a buffer before it...tho it appears to be more due to the tone shaping stuff.

The reason to adjust low end before clipping (Iain's suggestion) is that it changes the CHARACTER of the clipping quite a bit.  So putting it before the opamp is smart, tho in the FB loop worked for Ibanez.     I'd return the FB leg to its stock config and try what Iain suggests...not sure i like the mod in there, either...

If that doesn't work, I'd probably move more towards a soft clipper into a tone stack....clipping stage like TS, maybe another gain stage, tone stack, output.  The lows are baked into this for a reason - some dude got paid to design that in already     

[marcelomd]

Maybe what you need to decide is if you want a mids control before or after clipping. Before, like Mike said above, you change the character of the distortion. After, it works like a TS into a clean amp.

To me, the whole idea of the TS is cutting bass before and treble after distortion. You can argue that if it's not doing this, it's not a TS.

Examples using these two approaches:
- Tech 21's character series consist of a mid boost/cut before a clipper. This control is labeled "CHARACTER", not by chance. I like this approach. I think this was mentioned before;
- The other way to do it is doing like the Xotic pedals (BB, AC, RC). A TS followed by a Baxandall. If you cut bass and treble, you got high mids. If you boost bass and treble, you get scooped mids.

A third way to do it, that I don't remember seeing around, is putting clippers directly on a baxandall mids/treble control (or even a gyrator based thing).

EDIT: Quick sketch. I don't know if it works as-is

[GibsonGM]

After a long time screwing around with pedals on stages and for recording, the ultimate thing I came up with is to use something like a Marshall Guvnor (you can use a soft clipper like TS, too, if you like) With NO TONE STACK...followed by an EQ pedal.   25 pedals in one, that way    

What is common to basically all is that bass is cut at the input to avoid swamping the clipping section (MUD)...mids either seems to be unaffected, boosted, or cut, but often isn't user-variable.   High end is tamed with a high cut following clipping.

The TS is most often used to boost an amp, with either no gain applied or a small amount.  Maybe some people crank it and use it - I've never known any but they must be out there, ha ha.   It's not MEANT to be a versatile pedal...the mid hump is intentional.   It's understandable to want to tailor the sound, but I'm not convinced there's an 'easy' way to do this.    An EQ pedal, alone, could do very much the same job of tweaking the amp, AND offer whatever shaping you want. 
The TS is so simple it also limits getting in there and customizing it...I'm amazed there are so many mods at all!

[marcelomd]

After a long time screwing around with pedals on stages and for recording, the ultimate thing I came up with is to use something like a Marshall Guvnor (you can use a soft clipper like TS, too, if you like) With NO TONE STACK...followed by an EQ pedal.   25 pedals in one, that way    

What is common to basically all is that bass is cut at the input to avoid swamping the clipping section (MUD)...mids either seems to be unaffected, boosted, or cut, but often isn't user-variable.   High end is tamed with a high cut following clipping.

The TS is most often used to boost an amp, with either no gain applied or a small amount.  Maybe some people crank it and use it - I've never known any but they must be out there, ha ha.   It's not MEANT to be a versatile pedal...the mid hump is intentional.   It's understandable to want to tailor the sound, but I'm not convinced there's an 'easy' way to do this.    An EQ pedal, alone, could do very much the same job of tweaking the amp, AND offer whatever shaping you want. 
The TS is so simple it also limits getting in there and customizing it...I'm amazed there are so many mods at all!

Spot on. There are pedals that have their own sound (and work best into a clean amp) and there are pedals meant to work WITH the amp.

An now we're obligated to mention the G Drive which has a graphic eq before and a graphic eq after the drive section:

[GibsonGM]

I'd love to build or get my hands on one of them! 

[ElectricDruid]

I'd love to build or get my hands on one of them!

The easiest way would be to buy a couple of behringer EQ pedals and then put the guts of those in a box along with your favourite clipping stage. No-one would ever know, and I won't tell if you won't!

[GibsonGM]

Ya...no way am I going to assemble each gyator with its own opamp, and fit it in something like THAT ha ha.  The enclosure would end up being 12"x12"...the cost o the Behringer would be work it just in sliders...

[marcelomd]

A third way to do it, that I don't remember seeing around, is putting clippers directly on a baxandall mids/treble control (or even a gyrator based thing).

EDIT: Quick sketch. I don't know if it works as-is

Got a few minutes to spare and simulated this. Works as expected.

[snow123]

Well Snow, Iain suggested another way to do it - have you tried that?  This was about giving you more control of your MIDS when it started, remember?     If I was going to re-do the whole tone shaping setup of the TS, I doubt I'd do it this way.    If that was the case, I think I might go for a flat mids mod (AMZ etc), and then start from there.  It's really just a soft-clipping opamp with a buffer before it...tho it appears to be more due to the tone shaping stuff.

The reason to adjust low end before clipping (Iain's suggestion) is that it changes the CHARACTER of the clipping quite a bit.  So putting it before the opamp is smart, tho in the FB loop worked for Ibanez.     I'd return the FB leg to its stock config and try what Iain suggests...not sure i like the mod in there, either...

If that doesn't work, I'd probably move more towards a soft clipper into a tone stack....clipping stage like TS, maybe another gain stage, tone stack, output.  The lows are baked into this for a reason - some dude got paid to design that in already 

i did try Iains suggestion, but it basically raised all of the low end to where the mids are. and i have gotten SUPER CLOSE to what i want with the bass cut control, but the main issue is that the low end is raised by +5db.

and as a side note, im pretty sure i could make a whole 3 band eq in the feedback loop, 'cause while messing with different values for the bass cut control ive ended up accidentally making a mids and high end control, even though im already super happy with how the mids control is rn, and the tone control is essentially acting as the high end control (at least for how im using it).

[snow123]

and the main reason i dont want to do a full 3 band eq is 'cause i already have the enclousure drilled out with a waterslide decal on it and everything LMAO. and i did that when i thought i had the bass cut and mids control figured out (it was when i just replaced R7(the 1k resistor coming out of the clipping amp) with a 5k pot, and R4(the 4k7 resistor in the clipping amp) with a 10k pot).