Mixing different LFO Signals

[WhenBoredomPeaks]

I made an LFO which can go rail-to-rail from a 9V supply. I will have a sequencer and an other LFO (logic stuff like 40106) which can output signals as high as 8,5V-9V using a 9v supply. BTW this is sightly related to my previous topic, i will might try to mix envelope and LFO signals for fun.
If i simply connect my different LFO's to single output jack i will create a lot of problems i guess, so i have to use a DC mixer. That mixer should be active because i don't want to loose the "strenght" of my LFOs. (i want to be sure that 9v peaks stay at 9v after the mixing with dimed mixing pots of course)

Now this is impossible with a TL084 because it can't go rail-to-rail, the maximum voltage it can output from a 9v supply is around 7v i guess.

But if i use a rail-to-rail opamp in the mixer circuit a linked, will i be able to pass-through my 9v peaking signals without attenuation? (with "level" pot at max level setting)


http://musicfromouterspace.com/analogsynth/dcmixer.html

[WhenBoredomPeaks]

So i worked out that the gain of the opamps are 1 because of the two 100k resistors.

If i put a 200k resistor in the loop then the circuits gain will be 2.

Is that means that if i use a 6v input signal for example and the set the volume pot in front of the mixer to 50% of ot's rotation then it will be like a "halving" voltage divider and i will get 3v after the pot, then the opamp will boost it back to 2x3v=6v so the input and the output will be the same?

[PRR]

> Is that means that

Yes.

> LFO which can go rail-to-rail from a 9V supply.
> output signals as high as 8,5V-9V using a 9v supply.

It is a LOT easier to define your control voltage range smaller than your supply voltages.

Analog computers and the early modular synths defined control voltage as +/-10V using +/-15V supplies. Then the op-amps had 5V spare voltage to work with.

That schematic you posted calls for +/-12V supplies.

Since full-pull-down is not too hard, while full pull-up is still promlematic, you might define 0-5V control for 9V supply.

[WhenBoredomPeaks]

> Is that means that

Yes.

> LFO which can go rail-to-rail from a 9V supply.
> output signals as high as 8,5V-9V using a 9v supply.

It is a LOT easier to define your control voltage range smaller than your supply voltages.

Analog computers and the early modular synths defined control voltage as +/-10V using +/-15V supplies. Then the op-amps had 5V spare voltage to work with.

That schematic you posted calls for +/-12V supplies.

Since full-pull-down is not too hard, while full pull-up is still promlematic, you might define 0-5V control for 9V supply.

I have no "real" reason why i want to have a 0-9v control range. I just want to hear what happens if i "inject" my stronger control signal into existing circuits. For example i would disconnect the LFO of a Small Clone and i would use mine which is more flexible (more waveforms, speed range etc.) than the stock LFO so maybe i could hear something cool.

That schematic you posted calls for +/-12V supplies.

Yeah but for stompbox usage 0/9v would be fine i think. I don't want to use higher supply voltage with my LFO mixer because i don't want to control circuits using a 9v supply with a higher control voltage than 9v because i heard that can damage something.