Adding triple clip option to SD-1 with onoffon

[Steben]

Hi guys, what about this?
One could swap the LED with two silicons to get "true timmy style" but I think it does not matter that much.




On the other hand, the SD-1 block can be with a more compact LED as well.

[Vivek]

Could a pot be used instead of 3 position switch ?

[iainpunk]

so i was going to post about how it really doesn't matter what the clipping arrangement is, but then i realised this is in a feedback loop, not to ground so it matters way more, since it determines the relationship between the clean signal and the dirty signal being mixed together.
so ill say this: that's a clever switching scheme you came up with.

cheers Iain

edit: no a pot introduces more clean signal and does not change the threshold of the clipping (which decreases the clean signal)

[Steben]

so i was going to post about how it really doesn't matter what the clipping arrangement is, but then i realised this is in a feedback loop, not to ground so it matters way more, since it determines the relationship between the clean signal and the dirty signal being mixed together.
so ill say this: that's a clever switching scheme you came up with.

cheers Iain

edit: no a pot introduces more clean signal and does not change the threshold of the clipping (which decreases the clean signal)

Well, yes, choosing diodes here is +/- raising or lowering the point of gradual slipping into the original signal with offset.
More diodes or using LEDs makes for more distorted content vs clean content (with comparable gain shift of course). That's why I find the tube screamers too much soft clipping which can lead to bad low gain quality. And why led soft clipping arrangements are called "marshall" position by some aka "more amp like".

[iainpunk]

im honestly not a fan of feedback loop clipping, unless its inverting (which is hard clipping), but it seems to be a popular option so i guess that having the different options is a good thing!

[Mark Hammer]

A dozen or more years back I sold a TS-808 clone to one of Canada's better known blues guitarists to replace his TS-9 that had died.  What he particularly liked about it was the "warp" control I included.  This was simply a pot in series with one of the feedback diodes, that allowed him to vary the asymmetry of clipping.  Probably a more useful mod than going nuts with diode combinations.  I have no idea if he's still using it.

[Steben]

im honestly not a fan of feedback loop clipping, unless its inverting (which is hard clipping), but it seems to be a popular option so i guess that having the different options is a good thing!

Honestly, the higher treshold with its "less soft" character makes for a better balanced low to mid gain amp tone. Let's be honest: that is the major difference between a timmy and a tube screamer. Every time I had a ts under my feet it felt overcompressed, dull and of course midfocused. The higher treshold style is even present in the SD-1 already, albeit with asymmetry.
The very high gain settings on soft clipping feedback overdrive usually are unnatural as an amptone because they lack the ultimate squashed top drive.

One of the greatest guitar tones ever I find are on Deep Purple's Fireball album. Based on a treble boosted AC30, Blackmore nails a very natural creamy low to mid gain strat tone to die for.
Besides the hands of course, some of the Timmy generation pedals come very close.
An AC30 clips gentle into saturation, unlike a tight feedback amp like blackfaces and most marshalls.

[Vivek]

Does this bring anything useful to the table ?

[Steben]

Does this bring anything useful to the table ?

Yihaa... that is a particular one. full left is SD-1, full right is almost Timmy and in the middle gives higher output.... Odd one! But we like odd. It will definitely work.
The only problem with "ladders" is unnatural knees. This gives a sort of fizz. It means your pot probably needs a large enough value compared to the feedback resistor, which leads to a steep enough knee.

[iainpunk]

Does this bring anything useful to the table ?

i'd like to echo steben but add that in the middle, it will have the bad qualities of the tubescreamer, but just more... a mix of clean signal and fizzy mosquito sounds.

cheers, Iain