Build Your Own Clone Message Board

Built a Mimosa Jr. back in January and it went great! However, I've noticed that the output seems lower with 12 o'clock on the the level being noticeably quieter than when bypassed. Below are some pictures of the top of the PCB, I can get ones of the bottom but I'm sure you'll understand what a pain that can be so hopefully someone can notice something that I'm missing.

I don't see any component problems, though some of your solder joints run a bit to the "blobby" side. Very much doubt that that's a problem though, since the circuit apparently works properly, other than being a bit quieter than you'd like.

Why not just turn the volume up a bit more to match the bypassed volume? There's no guarantee with a compressor circuit that 12 noon on the volume control is going to be "unity gain". Also, the volume control is a log (A) taper pot, which rolls on slowly at first and then more rapidly in the last third or so of the sweep.

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“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

As long as there is an appreciable volume boost when the volume control is all the way up, I don't think there is anything wrong with your build. There is an internet myth out there that makes people think that noon on a volume control should be unity gain. This is almost never the case. As DVM said, this circuit is not specifically designed to be at unity gain at noon on the volume knob.

There is a simple trick to get it there. If you want the volume to be unity at noon, set the volume for unity gain and loosen the volume knob and tighten the knob so it is at noon. That way you can just set the control at noon and have it where you want it.

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MasterDelayer/Reverbrador/Ampaholic/TopJacker

So, it's not so much that I care if 12 o'clock is unity but rather that I feel that it used to be that way (I very well may be going crazy, so that's a possibility too). Unity seems to be around 3 o'clock. This mainly effects me because I occasionally used the level knob to smack the front of my Overdrive 2 (probably the best pedal ever) and it doesn't seem to do it like I used to. So, I completely understand where y'all are coming from BUT I'm 99% sure that it wasn't like this before. Then again, I very well may be crazy since I hadn't used the pedal since I had gone on a tour and could be remembering incorrectly. This is why when I saw this thread, I figured I might have had a similar issue.

Unity gain is rarely at noon with a pedal that uses a log taper volume pot. It's usually around 3 o'clock. Some pedals will use a linear taper for the volume, and that makes unity gain around noon or a little before it, but the last third of the pot's rotation is either very touchy or doesn't really do much of anything. So while the log taper pot may not have unity gain at noon, it does provide a smooth taper across the whole rotation.

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*patience is a virtue*

Please do not PM me. email is prefered. keith@buildyourownclone.com

Ah, sorry, it wasn't clear to me that the pedal had recently lost output volume. The TL074 IC would be the most likely culprit, but it's a pain to desolder 14 pins and clean up the eyelets for a new IC, especially when you don't know for sure that it's the problem. However, other things can also affect the output of compressor circuits. Have you changed the position of the Mimosa Jr. in your pedal chain, or put a new pedal in front of it? Any other changes in your signal chain recently?

Something else that could be useful to you would be to switch the volume pot to a linear taper, which will roll the volume on earlier in the sweep.

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

Is it possible the knob was bumped or impacted and moved position relative to the pot? That's kind of what Morgan was suggesting but in reverse.

BTW Morgan, that suggestion of moving the knob made me think of Spinal Tap - Nigel and Marty talking about "11" for some reason...in a good way

Sure it's possible, but that's easy to determine--is the mark on the volume knob at full CCW in the same place it was when you built it?

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

This is great to know and confirms my theory that I might be going crazy. In all seriousness this does help quite a bit!


This was kinda the answer I think I was looking for! Is there a way to test the IC so that I can rule that out before drastic measures? I had been using this bad boy in the front of my chain, so I don't think anything else would have effected it in that regard.


I wish this were the case! Unfortunately everything is where it should be but thanks for the suggestion.