How get more modern sound with the COT50?

[sebarb]

Hi guys, can we mod a COT50 for more modern sounding?
I like the dynamic, texture and the old school tone but switching between vintage and modern Mod can be interesting!
By the way, who can tell me what happen in section between the transistor E pin and the gain control, (47R + 47uf cap and 330R in parallel)?

Best regard

[GibsonGM]

Could you post a link to the schematic?  It is hard to know how it works if we can't see it! 

[gjcamann]

The COT50 is such a simple circuit, it is easy to sculpt the EQ. Take  a loook at Ivark's work on this:
http://revolutiondeux.blogspot.com/2008/02/clock-of-tone-50-modifed-cot50.html

However if my modern you mean higher gain, I suggest you try putting a boost in front and see what happens, try a SHO, you can get a board no larger than a pot here:
https://oshpark.com/shared_projects/nsJTeQK0

[bool]

Those one-transistor wonders can be made meaner by using a darlington transistor (fe. mpsa13) and increasing the nfb/biasing resistor (could go up to several meg-ohms). With that, you will get more gain and also more fizz, so some additional filtering will have to be glued-on (a couple-nF cap accross diodes). Personally, I'd use a LED/rectifier diode combo, but that's just me.

With that, you can also try to increase the input cap to get a slightly more menacing low-end.


IOW, whatever you can do to an Electra OD (not much really), you can do to a COT.

[sebarb]

Tank for your answers,
i tried already to increase the biasing resistor with pot, i got nice manageable low end or kind of headroom,
and SHO at the back of the COT, sound realy good to, give a touch of low end with sparkling hight!

But something is still missing for modern sound maybe some Mids??

[FiveseveN]

Previous posters have already pointed out the main issue: define "modern sound" first!

a touch of low end with sparkling hight [...] maybe some Mids??

What do you get when you add more lows, more mids and more treble?

[bool]

To get more "modern" (at least what I consider modern) tone, you IMHO really need to change to a darlington. This will also increase the input impedance a bit, which is imo also an important factor with how "modern" a tone can get.