yeah i need the same gain for both - and + phase signals. ideally amplification within the 20 - 40dB range using a (10k?) pot while i am fine tuning the rest of my circuit. at this point im not sure how hot i need the signal to be.
also, since the CMOS chips i'm using are the 4066 i'd have to configure them to do dual throw (which im not sure is even possible, maybe my brain needs some more coffee).
furthermore im concerned that a hi-z guitar input signal wouldn't pass nicely through a CMOS chip without some prior amplification......
also, since the CMOS chips i'm using are the 4066 i'd have to configure them to do dual throw (which im not sure is even possible, maybe my brain needs some more coffee).
furthermore im concerned that a hi-z guitar input signal wouldn't pass nicely through a CMOS chip without some prior amplification......
You can convert a 4066 to DPDT by using two switches with one control inverted from the other. You could also choose to use a 4052.
oh! for instance using a "not" gate transistor ?
still think i'd have to amp up the low guitar signal before running the signal through the CMOS...
Put your preamp stage before ZD's circuit, then you have same gain, plus phase switching. There ya go.
haha your replies are always posted one second before i even post...!
so...... if i add a preamplifier stage before Zero D's circuit...
electronically... how is that different from my original design?
i see that the inverting/noninverting inputs are not connected together, but the circuits are very similar!
id love to better understand what is going on...
if my design makes sense, AND isn't too different from Zero D's design AND allows me to use the 4066 without any dualthrow not gate wizardry - i think i might go with it - am i on the right track?
thanks guys....
electronically... how is that different from my original design?
i see that the inverting/noninverting inputs are not connected together, but the circuits are very similar!
id love to better understand what is going on...
if my design makes sense, AND isn't too different from Zero D's design AND allows me to use the 4066 without any dualthrow not gate wizardry - i think i might go with it - am i on the right track?
thanks guys....
I just wasn't sure your circuit would accomplish the inversion properly. So I did a sim and it does work fine. Your circuit with the single 4066 should work ok then. If you have any spare 4066 gates, I would parallel them if you can, just to lower the resistance as much as possible.
I just wasn't sure your circuit would accomplish the inversion properly. So I did a sim and it does work fine. Your circuit with the single 4066 should work ok then. If you have any spare 4066 gates, I would parallel them if you can, just to lower the resistance as much as possible.
okay! i will try and do that... thank you so much for all your help - will post back with results...
all the best,
úlfur
It is sort of a weird circuit though. With the switch closed, the op-amp has a gain of -1. With the switch open, you have a gain of -1, AND a gain of +2, so the sum (it's a difference amp actually) is +1.
But it does accomplish what you want, and with a single switch.
But it does accomplish what you want, and with a single switch.
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I only responded initially to the phase inversion aspect, as that was your main concern. So i expected the preceeding gain circuit to be still in place
Whichever circuit you go for, with the 100k & 100nf components around the 1st OpAmp, the bandwith will ONLY be about 16hz, so you won't hear Anything You need to change the cap to 100pf to give you a 16kHz f3. Or alter to suit.
Whichever circuit you go for, with the 100k & 100nf components around the 1st OpAmp, the bandwith will ONLY be about 16hz, so you won't hear Anything You need to change the cap to 100pf to give you a 16kHz f3. Or alter to suit.
If I may...Why do you want to be able to flip the phase of the guitar output? The reason I ask is because phase switching is usually done directly after the pickups to either have them in phase with each other or not, and obviously can't be done on a single pickup ax.
Mike
Mike
This kind of phase flipper with a single switch to ground is not new at all and should work properly. You will find the same idea in old phaser circuitry.
The feedback network of the pre-Amp is wrong, as ZD stated.
Pre-Amp gain should be less than 10x if you will avoid clipping during loud playing the guitar.
The phase flipper makes obviously audible differences in case you combine pickups -
remember "out of phase sound" used by mark knopfler, for instance.
The feedback network of the pre-Amp is wrong, as ZD stated.
Pre-Amp gain should be less than 10x if you will avoid clipping during loud playing the guitar.
The phase flipper makes obviously audible differences in case you combine pickups -
remember "out of phase sound" used by mark knopfler, for instance.
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