Tube Screamer Variant Frequencies Chart

[Aentons]

Here is a chart of frequencies and component values of a few TS variants including the TS9DX modes, the VFE Scream and Ice Scream flavors. I'm a big fan of the TS9DX +mode.

Tube Screamer Variant Frequencies
https://docs.google.com/spreadsheets/d/1ynpLuxMIX6JOicq6LVN6Av36fvGKRoH3DsCBONKk5-E/edit?usp=sharing


Please let me know if you see anything that needs to be corrected

[Aentons]

Here are my notes for the source of the Ice Scream info:

This is the VFE DIY doc:
https://www.dropbox.com/s/pd4wwctd7sp7kh9/ISCassembly.pdf


The following info is from the Ice Scream schematic that is published on the VFE Facebook page:

Ice Scream - Component Variations for Different "Flavors"
http://www.vfepedals.com/
Copyright © 2016 VFE Pedals - All Rights Reserved

VANILLA
Resistors LOW = 1K, VOL = 4.7K, MIN = MAX = 10K
Capacitors MAX = 0.1uF, HI = 47nF

MINT
Resistors LOW = 1K, VOL = 2.2K, MIN = MAX = 4.7K
Capacitors MAX = 0.22uF, HI = 47nF

SHERBET
Resistors LOW = 470, VOL = 1K, MIN = MAX = 2.2K
Capacitors MAX = 0.47uF, HI = 0.1uF


From Peter @ VFE Pedals in the comments on that same FB post:
"All Ice Screams had the capacity to utilize the same clipping configurations, so the difference was just in the overall gain & EQ range. If you got the Sherbet (which had the most range), you could dial in tones from the other two (though it was more difficult to fine tune low gain / boost settings)."

Ice Scream - May 15, 2016
The Ice Scream originally came in three "flavors". The mint version, seen here, featured asymmetrical clipping to enhance even harmonics and create a sweeter drive tone. The sherbet version, seen here, featured a more dynamic, symmetrical clipping setup, 6dB more gain than the mint version, plus extended EQ range. The vanilla version, seen here, was setup as a clean booster and had 6dB less gain on tap than the mint version.
All versions shared the same clipping options internally. The difference was primarily which clipping configuration was selected when we setup the pedal.
The final run ... will also have the extended EQ and gain range of the sherbet version, but will be setup with the asymmetrical ciipping of the mint version (clipping configuration can still be changed with internal DIP switches).

Q: Peter, how will the extended gain range affect the lower drive settings? Will it have the same amount of gain with the DRIVE knob counter-clockwise as the Mint version?
Also, will you include these final run mods for Pedal Wizard orders or are they exclusive to the final run batch only?
A: The drive pot has a sharper logarithmic taper than a standard logarithmic pot. This allows it to get a wider range of gain tones while still having the ability to fine tune lower gain stuff.
You aren't losing any range on the low gain end, just gaining an extra 6dB when the drive knob is maxed out.
Pedal Wizard orders can request whatever configuration they want (low, medium, high gain, and symmetrical, asymmetrical, or diode lift clipping).



From the VFE website (http://vfepedals.com/ice-scream.html):
"The gain stage shares much in common with The Scream and other tubescreamer variants. The amount of gain in the Ice Scream varies by version - Sherbet has the most, and Vanilla has the least."

[Aentons]

Here is where I got the Keely info:

Keeley modified TS9

http://www.robertkeeley.com/Audiokt88/tonecap.html
Edit: Looks like the above link isn't active anymore. Here it is if from wayback:
https://web.archive.org/web/20170425112108/http://www.robertkeeley.com/Audiokt88/tonecap.html

"When I modify a TS9 I start with a brand new unit.  The pedal is tested before and after the mod to make sure there are no problems with the unit.  I have found a couple of loose wires in some new units.  I change the IC to RC4558P.  This is what came in the earliest TS808's so I try to make this section as close to the original as possible.  The TI RC4558P is a VERY sweet sounding IC, very smooth distortion, not at all harsh.  I change the two resistors in the output section.  These resistors are changed to the same values that are in an original TS808.  The resistors were chosen in the TS808 to drive the input of a tube triode.  In the TS9 they were changed to reflect the fact that people were driving transistor amps more often.  I do not use carbon composition resistors here.  The reason I don't anymore  is two fold.  First, the drift in value and are not a tight tolerance part  Changes to carbon composition in the output and particularly the BROWN mod (1K ohm values around the opamp) will make each pedal sound different.  Generally these resistors are higher in actual value so the BROWN mod will actually make your pedal sound dull.  Because of the spacing of the material of the carbon composition they have a reactance (plus a resistance) to guitar signals.  This may explain the less high-fidelty tone that people describe as well as the increase in noise you get with a "brown" or "silver" mod (which by the way is just the 2nd mode of a TS9DX.  2 diodes in each direction for the clipping circuit, save yourself some money if you are after the silver, get a TS9DX and we will install the nicer caps for you..

Next, I change the capacitor that is connected to pin two of the op-amp.  This cap changes the frequency response of the feedback loop.  I change it to the next standard value (0.1uF metal film).  I have had only a few customers say that it caused too much bass in there system system.  Otherwise, everyone else has been happy with the flat frequency response this cap creates.  I like it myself.  It is not a bass boost, it is just changed to even out the response.  Most people complain about the bass loss when they engage a stock TS9.

After that I change two resistor in the drive circuit (51K--> 20K metal film and the 4.7K--> 2.4K metal film).  I change the values so that you have more distortion (about twice as much) as you turn the drive control clockwise and less distortion at the counterclockwise position of the drive control.  This has the effect of pleasing both crowds of people.  It has less overdrive in the low position and more distortion in the high position.  Throughout the middle of the drive control it is possible to get every stock TS9 drive sound.  This is really cool.

We also change the coupling caps from the NP electronlytics to the very nice Panasonic Metal film.  This is part of our Standard 808 MOD PLUS.  We also change the tone control cap to metal film so that the circuit is as hi-fi as possible.

Lastly, I check the unit out again.  We resolder the DC jack so that there is little chance for it to go out (a common failure in older well-used units). I check the unit for loose guitar jacks.  I pack the unit in bubble wrap to make sure there is no damage on its way to you!"