Building the Meat Sphere

[bcalla]

I did test it with guitar, and at some Meatball setting, low notes can become unpredictable as noted above.  The Moog switch brings it back under control.

That said, the Moog switch is not noticeable at most settings.

[yvarg]

I just had an interesting thought. Would I be correct in assuming that the effects loop on the Meat Sphere is turned off when the pedal itself is bypassed? I guess what I mean is: if I have a fuzz pedal plugged into the effects loop of the Meat Sphere, and I turn off the Meat Sphere, my signal will no longer be going through the fuzz pedal either, will it? If this is the case, I wonder how hard it would be to modify the circuit so that the effects loop is active even when the pedal is disengaged. I would rather not have to have two dirt pedals on my board just because one is in the effects loop of another pedal, haha!

[Taylor]

That's true, and I've heard people complain about the original and all the boutique clones because of the effects loop bypass. I think a particular switching arrangement can get around this but IIRC a 4PDT stomp switch is necessary.

[yvarg]

You must be thinking of a simpler solution than I am. My immediate thought was to wire two poles of the stomp switch so that when the filter is bypassed the effects loop is added into the bypassed signal, and when the switch is flipped and the filter is in use, the effects loop leads are directed back to the PCB. Of course, taking the LED into account, this requires a 5PDT footswitch. I don't think those exist; at least not for practical hobby use. So I was planning on using a 4PDT to activate a relay. Rather roundabout, but it would do the job, and there'd be space for it in that massive enclosure.

[bcalla]

I think Taylor's saying you don't need another LED.  If your Meatsphere is in bypass, the LED goes out and the effect loop is connected directly via the additional pole. Stomp again and the effect and LED come on and your loop is disengaged.

[yvarg]

I'm not sure I follow what you're saying entirely. I must have made it sound like I wanted to add another LED. What I meant was the stock version of the Meat Sphere's footswitch uses all three rows of contacts on the 3PDT switch (including the original LED on/off switching circuit that's standard in all true bypass pedals. What I'm envisioning for routing the effects loop requires an additional 2 poles on the switch, for a total of 5 poles needed in a switch. I'll draw up a diagram when I get home to clarify, since I'm not great at describing this, haha!

[yvarg]

This is what I had in mind. Maybe one of you has a simpler idea that involves less imaginary switch designs!

[lwatford]

Nsl32 sound like ass
Use proper led and ldr combo like the real unit

Thanks for this post.  I had mine finished and it sounded awful.  Only a few knob settings did anything - most knob positions turned off the effect entirely.  I had a terrible static/hiss on top of the effect.  This sounded like a mess of troubleshooting, but first thing I did was pull the NSL32s and pop in a pair of green LEDs and a couple of LDRs.  Bingo.  Sounds amazing.

what value LDR's did you end up using? I ordered some from futurlec, but that was months ago and haven't heard from them.

[bcalla]

I'm not 100% sure, I had them in stock for a long time.  I think they were from Tayda - I don't remember buying them anywhere else. 

http://www.taydaelectronics.com/photo-conductive-cell-resistor-ldr-650nm-radial-ke-10720.html

[lwatford]

The LED/LDR is so much better than the VCLs ever were! I used diffused green LEDs, and the medium LDRs from the RatShack pack. Much, much better. Now to get a refund from futurlec...

[LaceSensor]

You often need to chase futurlec, in some instances they are waiting on stock

I recommend the 2M dark (typically 10k-20k light / 2M dark) LDR with green diffuse LEDs for a good range of sounds from this circuit

[chicago_mike]

Theres a mod for the mutron III using the NSL-32's

I think I have over 100 NSL's I got for free that I will see if the mods work out okay.

[theokbird]

Hey there everyone,

this is my first post here, so hello!

i've built the meat sphere and it's very cool, works as expected, EXCEPT! I did the moog mod and when i switch it on there is horrible self oscillation(kinda cool, actually, but hardly useable, however you can tune it via color) and the envelope effect disappears.  did i just wire it incorrectly?  here's some pics:

[chicago_mike]

Red wire....

The one farthest from the cap and resistor...put that red wire down one lug to connect to the 10K resistor. 

[theokbird]

Red wire....

The one farthest from the cap and resistor...put that red wire down one lug to connect to the 10K resistor.  

AGH i knew i did something dumb... thanks! just switched it up, sounds very very cool, works as expected now, no more oscillation....only thing about is that horrible popping that occurs when switching...has there been a fix for that?  on certain settings the popping isnt noticeable, but on others its really insane

After listening and tweaking for awhile there are certain useable sounds, but many moments of self oscillation that can occur (particularly with electric bass, in moog mode as well)  but i guess this is just the nature of the pedal...  ironing out the right sound means taking notes and plenty of tweaking to figure out the settings that are actually useable.  i definitely don't know if i could use this live, seems a little too unpredictable.  how is everyone else using this pedal?  are you finding the same degree of unpredictability?

[chicago_mike]

Most controls on the meatball and other such filters affect the peak detector.  And really, while its cool to adjust these things...its really more a set and forget setup.

Check this out, Dave gives great info. 


http://www.youtube.com/watch?v=jllsqRWhjGM

[chicago_mike]

Got a question!!!

Should the blend pot actually be a dual ganged with a buffer after it?

[LaceSensor]

Got a question!!!

Should the blend pot actually be a dual ganged with a buffer after it?

no...
why do you ask that?

[chicago_mike]

Last time I used a pedal in the fx loop..in the 50% position of the pot...the volume had a drop off. 

[gilmour_pugliese]

Hi, after a bad experience with my first Meatsphere (equipped with VTL5C3), I've bought a second PCB... This time I wanna use LDR+5mm diffuse green led.
These LDRs are good or not?
http://www.ebay.it/itm/10PCS-LDR-Photoconductive-cell-1k-5528-Photo-resistenza-arduino-compatibile-/151352412368?pt=Componenti_elettronici_attivi&hash=item233d4e88d0

specs:
Model: GL5528
Maximum voltage (V-dc): 150
Maximum power consumption (mW): 100
Ambient temperature (° C): -30 --- +70
Spectral peak (nm): 540
Light resistance (10Lux) (KΩ) :10-20
Dark Resistance (MΩ): 1
100λ10: 0.6
Response Time (ms): rose: 20

thanks