MF-101 Envelope Filter Sensitivity

max3 · Post by **max3** » Thu May 11, 2006 12:20 pm

I was wondering if there is anyway to increase the sensitivity of the envelope on the mf-101? I am playing a bass through it even with the envelope set all the way to ten, I have to really pluck the string to get the envelope to open all the way. I have the output on my bass as high as it will go and the gain up to the point that it is almost about to distort. I have the mix at 10, the resonance at 8 and the cutoff a little above 250.

godzilla · Post by **godzilla** » Thu May 11, 2006 12:51 pm

yeah i don't know if this would distort or not

but you could try running the bass through a preamp before the 101

it depends whether the envelope follower uses the signal before or after the gain of the unit

if it does it before then you could have a nice distortion free sound with a lot of response

Spank · Post by **Spank** » Thu May 11, 2006 4:14 pm

can you use a compressor with a bass?

lg · Post by lg » Thu May 11, 2006 4:50 pm

Deke wrote:can you use a compressor with a bass?

it's done all the time. the dbx160 is a classic bass compressor...

max3 · Post by **max3** » Thu May 11, 2006 8:16 pm

I believe my problem is not enough signal to the mf-101's envelope to function. A compressor would just flatten my volume range so I wouldn't get any high peaks. Unfortunatly, the envelope only really opens up when I create a peak. I would like the envelope to work during my normal playing like I had with a qtron. I need to figure out a way to increase my signal such as a preamp or make the low pass filter more sensitive to my low signal. I am going to try the preamp tonight and see what happens.

lg · Post by lg » Fri May 12, 2006 5:01 am

lg wrote:
Deke wrote:can you use a compressor with a bass?
it's done all the time. the dbx160 is a classic bass compressor...

oops, sorry for the seeming non sequiter; i kinda forgot max3 was looking for a solution to his filter sensitivity (or lack thereof) problem. agreed a compressor wouldn't be a good choice here. a preamp or line driver seems like a possibility though. personally i would opt for boosting signal pre-filter rather than mess with the mf-101's sensitivity, as it would affect the unit's performance with other sources, maybe not what you ultimately want.

asd · Post by **asd** » Fri May 12, 2006 9:53 am

godzilla wrote: it depends whether the envelope follower uses the signal before or after the gain of the unit

curiousity question since i don't have the pedal, but would like to in the future. wouldn't the envelope follower need to be after the unit's gain? if it was before the gain i don't see how could the envelope could be even mildly effective with the wide range of signal levels that you can feed into the mf's.

it could go before the gain, but in my limited understanding that would seem to have a lot of inherent limitations like max3's problem that could be easily avoided. anyone have insight on this?

max3 · Post by **max3** » Fri May 12, 2006 2:13 pm

I tried the preamp and it did not increase the amount the envelope opened. Maybe it has to do with the low frequency of the bass as I noted while playing guitar through the pedal I get an excellent auto wha with each individual note. This auto wha is not as pronounced with the bass notes except when I really pluck the string. If I turn the resonance up, the effect is more pronounced but the origional tone of the bass gets covered up by that really strange tone that is produced by the pedal. All very cool but I was hoping to get more of an autowha effect out of the pedal.

hieronymous · Post by **hieronymous** » Fri May 12, 2006 2:17 pm

That sounds strange to me - you should be able to get a normal envelope follower sound out of it. Have you tried EQing the bass signal going into the pedal? Maybe you need to boost the highs and mids? Also, where do you have the mix control set?

max3 · Post by **max3** » Fri May 12, 2006 5:06 pm

I just adjusted the eq of my bass (more highs) and now I am getting the wwwwwwwoooooooooowwwwwwww I have been looking for. Figures that it was the most simple fix and I completely overlooked it. Thanks!

analoghaze · Post by **analoghaze** » Fri May 12, 2006 7:01 pm

hieronymous · Post by **hieronymous** » Fri May 12, 2006 9:42 pm

Glad we figured it out! I have an old Gibson bass with flatwounds and the big ol' humbucker that puts out NO highs whatsoever, and when I tried it clean through the MF-101, adjusting the frequency had no effect because the bass wasn't putting out frequencies that it could affect! So I thought maybe that was the problem...

peter ripa · Post by **peter ripa** » Sun May 14, 2006 10:29 pm

just route the cv from env out back in to cutoff cv in. attenuate to suit your need

eric coleridge · Post by **eric coleridge** » Thu May 18, 2006 7:02 pm

peter ripa wrote:just route the cv from env out back in to cutoff cv in. attenuate to suit your need

Even though this seems like the logical outcome, I've found that it doesn't work in practice on my MF 101 and it actually eliminates envelope. I haven't tried to attentuate the envelope voltage before sending it to the cutoff though (maybe this is the key).

I have to say that I was a little underwelmed by the envelope responce to Bass Guitar when I first got my MF 101 also. And I was also wondering if there was some way to increase the envelope sesitivity; Maybe there's a trimpot for this value? I haven't seen a schematic, but then it may not be labeled as such anyway.

The envelope works great with guitar or synth, but it doesn't have the same great responce with bass guitar as I imagined and in repect to a Mutron III (the classic 70s env follower for bass). Although, the tone is amazing regardless of what instrument is being played through. It has a much better tone than any of the Electro-Harmonix envelope followers, and if I adjust everything just right I can get most of the auto-wah sound I want. But I found that I have to turn the gain up at least 3/4s to get it to trigger properly, and I don't always want that much gain on the signal.

I think they should have a bass version maybe.

?

peter ripa · Post by **peter ripa** » Mon May 29, 2006 7:24 am

yes it doesnt happen very much. ive even routed the evn out signal, doubled it and added these together and then patching back in again to get what i want

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