Ways to soften the boost from a TL072 or [J]RC4558

[matopotato]

Having built and planning to build pedals with ICs and diodes for clipping I have used switches (rotary, dpdts etc) to bring in or out diode constellations. Then there is usually an option to have no diodes for either soft or hard clipping, only the IC, which makes the circuit a boost. Which is fine. But the volume level gets pretty high, so when switching to it you have to compensate with volume and gain.
Is there some way to tame or soften this IC only being a boost setup? Or rather how...

[idy]

One way is to have that diode switch a two or more pole, and one pole adds a resistor. This is usually next to the volume/output pot, a series R before the signal hits the pot. It isn't perfect, because the amount of "padding" depends on the setting of the knob, but it is generally good enough.

Other ways include changing the feedback loop Rs in the opamp. Depends on the circuit...

[antonis]

Just place a resistive voltage divider to dominate output signal amplitude in accordance with diode(s) forward voltage drop..
i.e. for an ideal op-amp (rail to rail output), +9V power supply and Si diodes, voltage division should be 0.65/4.5..
A more realistic choise should be a division of about 0.175 or so meaning a resistor ratio of 1/5.5 ..
You can switch on-off either series or shunt resistor, depending on their actual values and succeeding circuit impedance..

[matopotato]

One way is to have that diode switch a two or more pole, and one pole adds a resistor. This is usually next to the volume/output pot, a series R before the signal hits the pot. It isn't perfect, because the amount of "padding" depends on the setting of the knob, but it is generally good enough.

Other ways include changing the feedback loop Rs in the opamp. Depends on the circuit...

Thanks
Yes, I thought it was more simple and that there would be a more straight forward value to use, but I understand that it is more complex. Any rule of thumb for that series R in relation to the pot? (or other standard functions)

[matopotato]

Just place a resistive voltage divider to dominate output signal amplitude in accordance with diode(s) forward voltage drop..
i.e. for an ideal op-amp (rail to rail output), +9V power supply and Si diodes, voltage division should be 0.65/4.5..
A more realistic choise should be a division of about 0.175 or so meaning a resistor ratio of 1/5.5 ..
You can switch on-off either series or shunt resistor, depending on their actual values and succeeding circuit impedance..

Thanks,
I think I will have to read this a few times. It is a bit beyond my circuit knowledge at this point.
I have used R voltage divider for the "left over" part of an OP-amp and made it about 4,5 each so that the unused amp would not be left to "hang alone in the air" sort of.
In my case it is about using MXR Distortion + as foundation and then Jack Orman's variations of saturation and asymmetrical clipping. Breadboard until I figure out what I like and then put that in. Probably using rotaries and what not.
And let the "boost" option be one setting.
But having tried with LED, Si and Ge so far, they are quite different in forward voltage drop, so I doubt one R would solve it.
I obviously thought it would be more simple than this.
But many thanks for the suggestions.

[matopotato]

I first built an OD/Boost almost distortion with soft clipping based on Brian Wampler's video (his final circuit at around 10:40 https://www.youtube.com/watch?v=F-WHBgIowmU) on how to construct a pedal. He said it would be loud if not having any diodes in the feedback loop, and it is quite loud.
I set it up with one rotary going
Boost (no diodes)
1+1 OA74 (from an old 70's TV set or radio)
2+2 AA114/9 (I think, not so easy to read)
2+2 1N60
and
1+x 1N60 with the x being 1,2,3,4,5 or 6 from a second rotor.
I bit of an overkill, and the 1+x construction is mostly a case of "more or less" when you rotate x.
Best sound is the 1+1 OA74 IMHO.
I also followed his suggestion on changing the caps going to ground (C28, C29) with 2 SPDT's (I think) to allow for Treb, Mid or Bass character. It might have been more useful to combine the two locations into one SPDT.
(I did not find much use of having one T and the other B)
It was very hard to fit into the 125B, especially since I was dumb enough to use single core wire that kept breaking and rotaries with all them wires almost not wanting to stay under the lid.
But it works, and some settings keep surprising me.
I'm really not much of a guitar player, so I have no way of saying if the OD/Distortion is a good sounding one, it just sounds good to me.