Yet another McMeat build report

[axg20202]

Hi all,

I recently finished this Lovetone Meatball clone/workalike. I would recommend it to anyone looking to build an envelope filter. It does the autowah thang, but it does much more besides. I don't really like autowahs, fwiw.

I used the folllowing layout.
http://home.planet.nl/~remke063/mcmeat.pdf

I was tempted to use a PCB version that is floating around that has PCB-mounted switches, but decided against it because it didn't appear to be fully verified and ready to go. The off-board wiring isn't too bad to do if you take your time. Not a build for the new builder though.

Here's a picture of my build. Sorry, I don't have a gut shot but can post one if someone lilkes the look of a mad tangle of wires - the off-board wiring in this project is extensive. I think I made it pretty tidy inside considering.



As far as I know, there's only one significant mod out there, which is the colour pot wiring mod. It's a simple case of tying the wiper to the pot lug that goes to the 1.5k resistor on the board. Makes the colour control range more useful. Works well.

I also opted to add a footswitch and LED for the FX loop rather than using swtiching jacks as in the original Meatball. I guess I could have used switching jacks as well so that the status of the switch would not matter if nothing was plugged into the loop, but I considered this a waste of switching jacks. I'm still trying out different pedals in the loop, but mainly dirt boxes so far. The MXR Distortion + clone I have works well and adds some more bite.
I decided not to bother with the pedal inputs. This pedal hogs enough pedal-board real-estate already.

As for doing the dreaded off-board wiring, I just followed the schematic to do all of this and chose not to follow the Pisotones website diagrams, which I believe have some errors. The schematic is easy enough to follow for the switches and pots. I used 3P4T rotary switches.

The box is a Taiwanese DD from SmalleBear. After sanding, primers and base coats were applied with an airbrush (all Autoair paint) - I used aluminium base (medium) to get the sparkle and followed with several coats of Sunset candy to get to a gold colour. I then applied my graphics using a single sheet of thin laser printer adhesive label and clearcoated the box with 1k automotive clear using a spray gun. It really pings in the sunlight, not that it will get much in my cave-like studio. 

Alas, I don't have any sounds clips recorded, but will try to post some. 

[Processaurus]

Nice work, you should be proud!

[axg20202]

Thanks mate. I've been having a lot of fun making bwows, wumps and peeows since finishing it. 

[Barcode80]

any chance you could detail the specific parts from that layout that are mounted offboard? i'm having the damndest time figuring it out...

[axg20202]

Sorry, I must have missed your post. Hopefully you've figured it out by now. All the switches and pots are mounted off-board. As per my original post, it is a good idea to use the schematic to verify the hook-ups because I don't trust the diagrams on the Pisotones site. You could use both to be honest: for each connection on the Pisotones diagram, check against the schemo before soldering. From memory, I think that the pots in those diagrams have the controls facing towards you but the switches are shown from the back - bloody confusing. Take your time doing one wire at a time from the schemo and you'll be right as rain. Don't worry too much about lead dress - it will be a birds nest in there. How do you think the original pedal got its name? Answer: the back of the switches and wiring look a bit like a bunch of meatballs and spaghetti.

[Barcode80]

yeah, i figured it out. It was also confusing because although the pics showing just the pot wirings are form the front, when looking at the switch wiring any place where the switch goes to the pot that is shown from the back too. very confusing. I did just that though, got the schematic, and got all the switch wiring in place. I also managed not to have TOO bad a rat's nest, there is a lot of wire but I thought it out ahead of time and managed to do it conduit style (all wires on one common path that can be bound together).

I did notice something confusing though. The schematic and wiring in the project shows only 3 positions for the Hi to Lo switch, but the legending on the original indicates four (i'm assuming, Hi-dot-dot-Lo). Any ideas on that?

[axg20202]

Check the schemo again. The switche definitely has 4 positions to select between 15n, 6n8, 3n3 and 2n2 on each pole, it's just that the 2n2 caps are mounted on the board and the others are on the switch. This means that you need to wire up the switch for 4 positions, with one position making the switch open. This position uses the 2n2 cap on the board only, while the other positions select between the caps mounted on the switch.

[Barcode80]

i don't see any caps mounted on the hi_lo switch. The caps you refer to as far as I can tell are on the lo-pass/full/hi-pass switch.... Am i missing something?

[axg20202]

Er...yes, look again :-)
The 'Mode' switch (LP/HP/BP) is SW4 in the schematic (at the very bottom of the page) and has no caps mounted on it. The 'Range' switch which has the Hi-dot-dot-Lo settings is SW3 (directly above SW4 in the schemo) and has switch-mounted caps associated with each pole of the switch (SW3-A and SW3-B on the schemo) and two 2n2 caps on the board, one for each pole of the switch.  I'm thinking that the reason your 'Range' (Hi-dot-dot-Lo) switch only has three positions is that it's actually your Mode (HP/LP/BP) switch.  Do you have a mysterious 4th setting on what you think is your Mode switch? :-)

[Barcode80]

you are probably right. I used the pisotones wiring diagram and now that i look at it, the switches don't seem to be in the same spots as on the original, so i think i wired the wrong ones in the wrong place!

[axg20202]

I think those Pisotones diagrams serve more to confuse than assist. I wish they would either correct them or take them down. Don't get me wrong, It's great that people create info like theirs to assist in DIY projects, but the info has to be correct....

Anyway, I'm off to learn about world history using Wikipedia...

[nosamiam]

Nice build, agx. Very impressive. I was wondering where you got the thin laser printer adhesive label you mentioned in your post.

[axg20202]

Thanks. Can't remember exactly the stuff I used. To be honest, now that a bit of time has passed since I built this, I would not recommend covering the entire face of a pedal with such a material and then clearcoating - the finish doesn't last because the clearcoat doesn't take properly on the surface. After several months the clear started to crack. I would recommend using float-off decals instead. More effort but more durable once its cleared. I might strip it down and paint it again one day. You live and learn.....

[nosamiam]

Ok thanks. I'm looking for something to use on a big panel. Tough to find. I was thinking about Lazertran, but I don't have an oven big enough to bake it in that I don't use for cooking.