MXR Envelope Filter, does it hold up an Ibanez Auto Filter?

[sovtek50]

Once upon a time a stupid young man sold his Ibanez AF-9. Little did he know one day he'd become a effectomaniac and would miss this little box.
That guy is me. I'm older but wiser now these days, plus, I'm able to build my own boxes. I got hold of an Ibanez AF201 schematic, but not the layout, which is a problem to me.
So I think i'll try the MXR EF instead, which should be easy to do, thanks to the marvellous GGG site.
Question: Anyone built that one and was happy?

[lightningfingers]

I've never played an Ibanez AF-9, but I waz very pleased with the MXR envelope filter.
I had issues finding the unusually huge resistor values though...
hih

[StephenGiles]

What was wrong with 2 x 10meg or even 3 x 6.8meg resistors?

[Mark Hammer]

Depends where you live, Steve. I imagine there are plenty of places where getting anything above 2.2M is a little more difficult.

As for comparing the AF-9 and the MXR-EF, they are somewhat different beasts. The AF-9 sits squarely in the Mutron III camp, having a choice of filter types, filter range, and drive direction.

In contrast, the EF uses a simpler 2-pole filter instead of a state-variable filter. Where it tended to differ from its counterparts was the inclusion of a variable attack time control.  That, for me, was always the most attractive feature of the unit, since it allowed me to make the feel suit the song.  I found many units of the same era tended to have plenty of tonal options but the feel of the sweep would often conflict with the material one wanted to use it with.

Because of the inclusion of variable resonance, and the quick, broad sweep that all of the various envelope controlled filters from the Mutron category had (see here: http://filters.muziq.be/type/filter/envelope), they were prized for their in-your-face sound, where the capacity for nuance that the MXR unit had tended to be overlooked.  Armed with the various mods that the Tonepad A-Gua board supports, and the little mods that Steve Giles and myself (but mostly Steve) were able to provide, the MXR unit is capable of approaching some of the things that people liked Mutrons for.  Still not the same thing, but able to accomplish more in-your-face things than before, while not losing any of the nuance capabilities.

[hank reynolds 3rd]

i got a schematic for the afl201 and am working on drawing up a pcb
http://www.8bitsindgenug.net/afl.png

i'm gonna make it w/out the fet switching but I'm not quite sure how to go about it...
think i just need to get rid of the fets/surrounding resistors etc, that connect from the o/p and input and the transistors etc at the bottom of the schem...
I'm working on something else at the mo, but from what i can see ,the ibanez is like a mutron the uses fets aswell as light dependent resistors


cheers
sam

[DiscoFreq]

That's a schematic for the AFL, not the AF-201 (you're mixing the names ). The AF-201 (and AF-9) has a high-pass filter, the AFL doesn't.

Sovtek50, Hank:
let me know if I can help you with a picture of the PCB of an AF-201. I have an AF-201 and an AFL.

BTW, I was a stupid young man too: I repainted the AF-201 (trying to hide the "secret weapon" that I bought for 12$ (8 years ago)), I regret that very much now...  

[rocket]

the Ibanez AFL (and AF201) are very similar to the Mutron (or RG's clone Neutron) - you can look there for how to connect the highpass switch.

[hank reynolds 3rd]

i think input for the high pass comes after the second opamp (starting from input)...