Building the Meat Sphere

[Taylor]

I think that should work OK, the attack time is slower than the VTL5c3 but you might like that more?

[gilmour_pugliese]

My first Meatsphere was poorly sensitive to the dynamics... I've checked the PCB several times (everything is ok) and changed a lot of 1458 but the filter was always too poor  
Now I've picked another PCB and, after testing it with the old VTL5C3s, the envelope is still not good  
I've thought to buy another pair of 5C3, but after reading some impressions here, I'm thinking to try 5mm diffused green LEDs + LDRs... Vactrols are too expensive and maybe this is not the perfect choice for this pedal  

There's a way to check a VTL5C3?

[alanp]

As always, socket if you want to swap values or audition components in a circuit. If you've found the Magic Unicorn Part for that position later, you can solder it into the sockets if you like.

[PackardGoose]

Well that's strange... I posted a couple questions here yesterday and they seem to have completely disappeared.  Anyhow, I have a PCB on order, and I THINK I have all the right parts on order now between Smallbear and Mouser. Can't wait to get going!

[Taylor]

Well that's strange... I posted a couple questions here yesterday and they seem to have completely disappeared.  Anyhow, I have a PCB on order, and I THINK I have all the right parts on order now between Smallbear and Mouser. Can't wait to get going!

Something weird happened to the forum, seems some posts from the last few days got deleted:

http://www.diystompboxes.com/smfforum/index.php?topic=109469.0

This forum does seem to be the target of hacking sometimes. These things are always reminders for me to donate to the forum, knowing how much trouble Aron is going through to keep it up and running.

[PackardGoose]

One of the questions I had was about incorporating the Moog mod.  That's done with a DPDT switch right? So if I used an ordinating 3pdt foot switch I could use the third set of poles to switch a status led, is that correct?  I think I would need that since there's no visual indication of a foot switch's setting.

Taylor, I wasn't sure what lead spacing the caps should be, but it looked like 5mm is pretty standard based on what Smallbear stocks. Is that what the Meat Sphere uses?  I hope that's correct since it's what I ordered.

I have some diffused green LEDs, and ordered three different pairs of photocells from Smallbear to try out in sockets.  None of them exactly matched the specs that LaceSensor recommended earlier in the thread, but hopefully one will work well.

[Taylor]

Yes, 5mm spacing is right, I recommend box film caps to fit cleanly. I don't personally worry about brand so the Topmay caps at Small Bear are fine, as are Epcos, AVX, Kemet, etc. I haven't done the Moog mod but you're right that you can use the third set of switch contacts on a 3pdt to switch an LED on.

[yvarg]

So I just finished boxing up a build of the meat sphere. So far, I'm veryy pleased with it. It makes great, funky noises so far, but mine is still a little buggy. For example, when I turn the trigger direction switch from the "up" position to the "down" position, it seems to kill the power to my pedal. The only way to get ANY sound is to turn the blend knob all the way counter-clockwise, so that some of the clean signal comes through. I also put a switch in mine to toggle between the "moog mod" and the original components. The moog mod is fantastic! It really tames the insane bass resonance of some notes on my pedal. I remember seeing that some folks had placed a resistor in parallel with two lugs of the "color" pot earlier in the thread, but I never could find any info on the value of the resistor. Anyone have any brief info on this color pot mod? I'm trying to upload a photo of my pedal, but imgur is being obnoxious right now. I'll post a photo of my build later though; as it was my first time working with waterslide decals, I'm fairly proud of the results.

[tremelo68]

Anyone interested in buying one boxed and working but not finished (knobs, graphics, etc)?

[tremelo68]

Here's some pics of it. Asking $75+shipping.

[Govmnt_Lacky]

Might want to move that to the For Sale section... 

[tremelo68]

Sorry. Will do

[Beo]

I'm still struggling with my build. Using the LM1458 and green diffused LED + LDR. I'm seeing some of the weirdness reported by other builders; poor sensitivity, effect loss and generally inconsistent behavior with the controls. Seems to work different in and out of the box too. I'll keep debugging. One thing that tripped me up is that the board layout is slightly different than the schematic, with in-line resistors / pots order switched... perfectly fine but made ringing out connectivity and grounds a little tricky. If anyone has discovered any tricks or gotchas to getting a consistent build, let us know!

Not having the real thing makes it difficult to know how it should work, and respond to the controls. One thing I am interested in is figuring out which controls and switch settings are most usable for guitar. I would like to do a schematic / layout for a simplified version, one that keeps the main useful controls and filter/trigger settings for guitar use. Might then be able to use regular toggle switches instead of rotary for a smaller footprint. Anyone have any comments on which controls and switch positions seem most useful for guitar (or which ones have little usefulness)?

[nocentelli]

Half bandwidth, up swept LPF (i.e. harder picking = more treble),  attack fully off, decay fully on, blend fully wet, sensitivity half/set to taste, colour and intensity half/to taste. The key (ime) seems to be that attack has to be set very low, and decay set high to get a good noticeable sweep: you can lower decay for a shorter, quicker sweep, or you can slightly increase attack from minimum, but the filter will not sweep at with combinations of higher attack and lowered decay settings. Additionally, the down sweep mode needs a higher sensitivity setting to get it to trigger: I tend to flip the bandwidth to full whenever I use the down sweep to give it more signal.

[Beo]

Half bandwidth, up swept LPF (i.e. harder picking = more treble),  attack fully off, decay fully on, blend fully wet, sensitivity half/set to taste, colour and intensity half/to taste. The key (ime) seems to be that attack has to be set very low, and decay set high to get a good noticeable sweep: you can lower decay for a shorter, quicker sweep, or you can slightly increase attack from minimum, but the filter will not sweep at with combinations of higher attack and lowered decay settings. Additionally, the down sweep mode needs a higher sensitivity setting to get it to trigger: I tend to flip the bandwidth to full whenever I use the down sweep to give it more signal.

Thanks. Maybe my pedal is normal, and I'm overdoing it on the controls. I'll try out your suggestions. This info makes me think the circuit could be reworked to be less finicky, although maybe less versatile.

[Beo]

Okay, getting much better sounds out of this now. Seems like I need sensitivity dialed in for my guitar, attack low and decay high. Then I need colour and intensity all the way up. With this, I can pretty much trigger the filter in most switch positions and get different sounds. I still think somethings not right, as decreasing colour from max seems to kill the trigger. And only in a few settings can I up the attack or decrease the decay and keep the filter. Any one else find that colour needs to be maxed?

Here's some helpful links:
http://www.diystompboxes.com/smfforum/index.php?topic=65545.0
http://www.effectsdatabase.com/model/lovetone/meatball#

[Beo]

Some eye candy...

[nocentelli]

Wow,  that is beautiful. RE: the colour pot - do you have lug 1+2 connected? Some schematics (not sure about Taylor's) have all three lugs connected to different spots, leading to very little resonance (and so barely noticeable sweep) until the colour is almost max'ed: with lugs 1+2 tied and connected to the first filter non-inverting input, and lug 3 to the bandpass output, the colour control gives a smooth increase in resonance across the whole of the pot's travel.

[Beo]

Wow,  that is beautiful. RE: the colour pot - do you have lug 1+2 connected? Some schematics (not sure about Taylor's) have all three lugs connected to different spots, leading to very little resonance (and so barely noticeable sweep) until the colour is almost max'ed: with lugs 1+2 tied and connected to the first filter non-inverting input, and lug 3 to the bandpass output, the colour control gives a smooth increase in resonance across the whole of the pot's travel.

I don't know of anyone else who has come across this, but this is news to me. All other schematics I've seen have all three lugs connected separately. It's late, so I won't try jumpering lugs til tomorrow night. Your explanation is pretty clear, but here's a snippet of Taylor's schematic that shows the colour pot wiring. Thanks for helping. The people on this site are awesome!

[Beo]

By they way, the inspiration for the pedal layout is Mike Gordon of Phish... awesome bass player. He uses the meatball for some killer bass runs, including the intro to down with disease. Being a guitar player, I'm hoping to lock in one or two funk settings I can rely on. This filter seems sensitive...