Brett
Well-known member
- Build Rating
The Mos-Tron Envelope Filter
Where it came from...
I've wanted to try an envelope filter like the Mu-Tron III or similar for a bit and came across this post by Dyaln159 on freestompboxes.org when browsing.
What is it...
It's an interesting take on the envelope detection and control circuit in that he doesn't use typical optical components to control the envelope, he uses MOSFETs. Even more cleverly, he makes use of a common (and relatively inexpensive) CMOS chip that already includes matched transistors. His circuit has similar features and controls to the Mu-Tron envelope filter so I deemed this one the Mos-Tron Envelope Filter and dressed it up to pay tribute to the original.
Modifications...
Nothing that should alter the sound in any way. I subbed dual op-amps in place of the quads that the original schematic called for because it made it easier to separate the audio circuitry from the envelope detector circuitry.
Sounds
Funky...but in a good way. This circuit is not an easy one to dial in, as I assume is the case for a lot of envelope filters. Once you find a combination of controls that works for you, it sounds great, getting there is a bit of a quest though. I plan to spend more time with it and feel that Dylan159 did a nice job on this circuit, I appreciate his effort to do something unique!
Enclosure
Winked Silver 125B from Tayda. Tayda handled the UV printing as well (double white, gloss varnish). I had them drill the enclosure as well, too bad I used the wrong drill file, lol. I'll be damned if I let that happen again.
Circuit Board(s)
This is my first time designing a stacked board design in a 125B. I'm happy to report that it was a success and I couldn't have been happier when it fired up on the first try, that's one hell of a feeling, isn't it? I separated the boards using a total of five pin socket/header combos and added a single standoff in the corner for additional reinforcement/longevity.
I also designed the board you see at the top for I/O. The Soft-Touch Relay True-Bypass is a modified version of @Chuck D. Bones's Simple Relay Bypass that accepts up to 24V input and has isolated LED SW points for compatibility with other circuits. All components, sans jacks, CLR, LED, and pads are SMD on the Soft-Touch Bypass I/O board.
You're ready to see this thang aren't you? Do me a favor and don't judge the knobs, please? All this work and I accidentally ordered the 20mm knobs for the top two when I meant to order the 15mm. Over here looking like Sloth from the Goonies... I'll have them on the way with my next SBP order and will try to remember to update the pics when they come in. Here it is in all of it's glory:
Special thanks to Dylan159 over at freestompboxes.org for providing this circuit and to @Chuck D. Bones for the bypass circuitry!
Thanks for reading!
Where it came from...
I've wanted to try an envelope filter like the Mu-Tron III or similar for a bit and came across this post by Dyaln159 on freestompboxes.org when browsing.
What is it...
It's an interesting take on the envelope detection and control circuit in that he doesn't use typical optical components to control the envelope, he uses MOSFETs. Even more cleverly, he makes use of a common (and relatively inexpensive) CMOS chip that already includes matched transistors. His circuit has similar features and controls to the Mu-Tron envelope filter so I deemed this one the Mos-Tron Envelope Filter and dressed it up to pay tribute to the original.
Modifications...
Nothing that should alter the sound in any way. I subbed dual op-amps in place of the quads that the original schematic called for because it made it easier to separate the audio circuitry from the envelope detector circuitry.
Sounds
Funky...but in a good way. This circuit is not an easy one to dial in, as I assume is the case for a lot of envelope filters. Once you find a combination of controls that works for you, it sounds great, getting there is a bit of a quest though. I plan to spend more time with it and feel that Dylan159 did a nice job on this circuit, I appreciate his effort to do something unique!
Enclosure
Winked Silver 125B from Tayda. Tayda handled the UV printing as well (double white, gloss varnish). I had them drill the enclosure as well, too bad I used the wrong drill file, lol. I'll be damned if I let that happen again.
Circuit Board(s)
This is my first time designing a stacked board design in a 125B. I'm happy to report that it was a success and I couldn't have been happier when it fired up on the first try, that's one hell of a feeling, isn't it? I separated the boards using a total of five pin socket/header combos and added a single standoff in the corner for additional reinforcement/longevity.
I also designed the board you see at the top for I/O. The Soft-Touch Relay True-Bypass is a modified version of @Chuck D. Bones's Simple Relay Bypass that accepts up to 24V input and has isolated LED SW points for compatibility with other circuits. All components, sans jacks, CLR, LED, and pads are SMD on the Soft-Touch Bypass I/O board.
You're ready to see this thang aren't you? Do me a favor and don't judge the knobs, please? All this work and I accidentally ordered the 20mm knobs for the top two when I meant to order the 15mm. Over here looking like Sloth from the Goonies... I'll have them on the way with my next SBP order and will try to remember to update the pics when they come in. Here it is in all of it's glory:
Special thanks to Dylan159 over at freestompboxes.org for providing this circuit and to @Chuck D. Bones for the bypass circuitry!
Thanks for reading!
