Lets talk about blend circuits...

[flanagan0718]

I am currently working on a 2 in one build. They are both pretty simple circuits, how ever i am wanting to add a couple extra controls. I would like to add a blend option to control how much of effect 1 goes into effect 2. I would also like to add a wet / dry blend to this. Has anyone here done this? Is it as simple as adding a jfet blend between the two effects and a jfet blend from the dry input? Any info / advice would be helpful. Thanks guys.

-Mike-

[jkokura]

A simple jfet blend? Perhaps you need to be more specific.

A lot of the reason I ended up producing the panner and paralyzer circuits the way I did is because I found that basic blend circuits don't actually accurately 'blend' the way we want. Usually we want things to go smoothly from full dry to half/half to full wet, but unless the circuit includes grounding the dry or wet signal, you won't get that from a basic jfet blender.

So, it sounds more like what you're needing is a mixer of some sort, something that allows you to put the circuits into parallel and then mix them on the output. Does that sound right?

Jacob

[flanagan0718]

A lot of the reason I ended up producing the panner and paralyzer circuits the way I did is because I found that basic blend circuits don't actually accurately 'blend' the way we want. Usually we want things to go smoothly from full dry to half/half to full wet, but unless the circuit includes grounding the dry or wet signal, you won't get that from a basic jfet blender.

So, Yes and no. The two circuits I'm blending together are a fuzz and ring mod. So clarity for those is kind of irrelevant. The ring mod has a little fuzz to begin with.

For the dry / wet blend yes it would be good to have it be super clean but taking into consideration the two effects I'll be using i understand it won't be perfect.

[midwayfair]

A single buffer followed by a stereo (dual gang) pot (essentially lossless) or use RG Keen's panner circuit (JMK's PCB is that circuit). RG's uses a single-gang pot but requires make-up gain. There is no other one-pot solution that doesn't cause odd volume changes between the center and extremes of the pot's travel.

If both effects have volume pots, though, you can just buffer the input and run them in parallel, and then you don't have to add any pots at all and you have full control over the volume of both.

[dbp512]

Are there any notable differences between parallel circuits with dual volume controls vs a blend pot? I was thinking about running parallel gain stages based off the Empress Multidrive, but I'd start simple and experiment a lot. To start I was thinking about a clean boost in parallel with a bluesy drive to see how that would sound. I feel like a blend pot would sound a lot like a gain control, but would it be too different from the sound I could coax out of a pair of volume pots? I might forgo that for blending two different flavored drives. Sorry if its dealing the original question, but I felt like it was the appropriate place to ask.

[blearyeyes]

If both effects have volume pots, though, you can just buffer the input and run them in parallel, and then you don't have to add any pots at all and you have full control over the volume of both.

Jon, when you say "input" do you mean the input of the new mixer circuit?

[midwayfair]

If both effects have volume pots, though, you can just buffer the input and run them in parallel, and then you don't have to add any pots at all and you have full control over the volume of both.

Jon, when you say "input" do you mean the input of the new mixer circuit?

The input of the whole shebang. You need a buffer to split the signal at the input, so that the input impedances aren't in parallel.

There's no mixer circuit in that case. You're just running two effects with volume controls in parallel.

If you go with an op amp buffer you might as well use the other half for an output buffer as well, but a four-component FET input buffer is fine.

[flanagan0718]

If both effects have volume pots, though, you can just buffer the input and run them in parallel, and then you don't have to add any pots at all and you have full control over the volume of both.

Jon, when you say "input" do you mean the input of the new mixer circuit?

The input of the whole shebang. You need a buffer to split the signal at the input, so that the input impedances aren't in parallel.

There's no mixer circuit in that case. You're just running two effects with volume controls in parallel.

If you go with an op amp buffer you might as well use the other half for an output buffer as well, but a four-component FET input buffer is fine.

Ok I'm starting to understand this a bit more now. However I've read several places that if i put a buffer before the fuzz it will tame it. So are both outputs from the buffer (being used to split the signal) buffered? I would assume yes. Right?

[jkokura]

If both effects have volume pots, though, you can just buffer the input and run them in parallel, and then you don't have to add any pots at all and you have full control over the volume of both.

Jon, when you say "input" do you mean the input of the new mixer circuit?

The input of the whole shebang. You need a buffer to split the signal at the input, so that the input impedances aren't in parallel.

There's no mixer circuit in that case. You're just running two effects with volume controls in parallel.

If you go with an op amp buffer you might as well use the other half for an output buffer as well, but a four-component FET input buffer is fine.

This essentially is what the JMK paralyzer is. You can use it to buffer/split the input, then send the signal to two effects, then pan between them after their outputs, blending between them before an output buffer and mono output.

Jacob

[blearyeyes]

If both effects have volume pots, though, you can just buffer the input and run them in parallel, and then you don't have to add any pots at all and you have full control over the volume of both.

Jon, when you say "input" do you mean the input of the new mixer circuit?

The input of the whole shebang. You need a buffer to split the signal at the input, so that the input impedances aren't in parallel.

There's no mixer circuit in that case. You're just running two effects with volume controls in parallel.

If you go with an op amp buffer you might as well use the other half for an output buffer as well, but a four-component FET input buffer is fine.

Ok I'm starting to understand this a bit more now. However I've read several places that if i put a buffer before the fuzz it will tame it. So are both outputs from the buffer (being used to split the signal) buffered? I would assume yes. Right?

I think it would negate the pickups complex  interaction  on the input of the fuzz circuit. This is a WAG on my part. (wild ass guess) maybe Jon has some input.

[Lubdar]

I'm kind of curious about this as well.  What if a fuzz is being blended in and out using the JMK panner?

[flanagan0718]

I'm kind of curious about this as well.  What if a fuzz is being blended in and out using the JMK panner?

Well now that would really depend on what I get to sound better. I am torn between two. The Raygun (freppo's) and a modded Fat Fuzz Factory (the mod being fixed resistors for some controls).

[bcalla]

Mike, did you consider GPCB's Paramix?  You can set wet/dry levels separately.  In your case you could have both signal paths wet - one for each of the 2 effects in your build.

[JC103]

Also remember to keep an eye/ear on the phase. If the two circuits are out of phase, chaos* will be the result.

*chaos = funny sounds that are undesirable 99% of the time

I'm hoping JMK adds a phase switch to the paralyzer one day. I think the GPCB circuit has a phase switch:
http://www.guitarpcb.com/apps/webstore/products/show/3456364

[selfdestroyer]

I have always had a heck of a time with FET blending with RAT pedals. The phasing is always off and sounds "hallow" but they work fine on BMP circuits.

Cody