DOD - FX32 Meat Box  [schematic]

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Dan N
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Post by Dan N »

So, anyone know where the dry out is? I don't see it on the schematic.

soulsonic wrote: I found one mistake in the factory schematic: they have pin 4 of the M1134P labeled as going to "+V Bias" when it should instead be connected to pin 5 (the regulated 5v output).
The DOD pcb shown uses +V Bias.
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Post by Dan N »

For the sake of posterity, the dry out is just a jack hardwired to the input jack. :slap:
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rapmusic
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Post by rapmusic »

How does it sound? I know this is sort of a harsh noise holy grail.

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Post by neoflox »

Come on guys - what happened to the PCB layout and the stripped schematic? I am gassing for one of these and I bet I'm not the only one.

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EricssonB
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Post by EricssonB »

I found a PCB manufacturer that is just miles from my house and I sent them an email to see if they can help expedite the process of translating schematics to PCB. I'll let you guys know in a day or few. :thumbsup

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Post by MANTIC »

Hello fellow internetters. This forum topic helped me do what needed to be done- clone the meatbox! Just finished working out all the kinks last week. Lot's of optional upgrades on this baby, too. Here's some teaser photos:

http://www.facebook.com/ManticConceptual

More info to come next week.
Enjoy!

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Post by EricssonB »

MANTIC wrote:Hello fellow internetters. This forum topic helped me do what needed to be done- clone the meatbox! Just finished working out all the kinks last week. Lot's of optional upgrades on this baby, too. Here's some teaser photos:

http://www.facebook.com/ManticConceptual

More info to come next week.
Enjoy!
Found your page, liked it. Let's see some video!

...

Anyways, I've been busy with a few preamps that I've been working on, so once I wrap them up I'll be looking into making a layout for the Meatbox. Anybody else made one yet and willing to share? Mine will be a few weeks out.

PCB was a bust. Definitely cost-prohibitive, and sortof a hassle. Old-fashioned way on a perfboard it will be.

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Post by mrballs »

I'm trying to understand what's going on in this circuit and I've a few questions for anyone kind enough to help.
(I'm still green electronically so pls forgive any gross ignorance)

The +Vbias going into C9 makes no sense to me. What purpose would this serve other than to lower the reactivity of C9?

Also, is the section (going left to right) from Q2 to PIN8 of the M51134P a band pass filter? The M51134 datasheet example schem has a BPF in this position so that's why I'm guessing that.

If my last assumption is correct, I can't help but wonder if a BPF wouldn't help tidy up the responses of circuits like the Shocktave or nasty octave down circuits.

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Post by EricssonB »

mrballs wrote:I'm trying to understand what's going on in this circuit and I've a few questions for anyone kind enough to help.
(I'm still green electronically so pls forgive any gross ignorance)

The +Vbias going into C9 makes no sense to me. What purpose would this serve other than to lower the reactivity of C9?

Also, is the section (going left to right) from Q2 to PIN8 of the M51134P a band pass filter? The M51134 datasheet example schem has a BPF in this position so that's why I'm guessing that.

If my last assumption is correct, I can't help but wonder if a BPF wouldn't help tidy up the responses of circuits like the Shocktave or nasty octave down circuits.
Got me beat on all of this. I just build them as spec'd. Taking a few weeks off to move into a new-to-me house, then I'll start the cloning of the schematic.

*bump*

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adapt
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Post by adapt »

oh god... a layout for this...

:hug:

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Post by MANTIC »

Well.... It's been a little over a week. but here's a side by side video of a DOD fx-32 Meat box, Along side the Density Hulk (meat box clone). We've taken out the 4007 Dual inverter and made it True bypass. It sounds great, but here you be the judge

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Post by Bernardduur »

The 'new' DOD Meatbox
DOD - Meatbox.JPG
Not true bypass; dry out is now a stereo jack on the output.
Mine has a very low output on the octave setting (octave full); I mailed Digitech for some support but they haven't answered yet.
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zelasa
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Post by zelasa »

Hi Friends!

Bernardduur , The Schematics is confirmed? I just compared with the Original Meatbox and there are some big differences.

Thank you!

Luis

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Post by Bernardduur »

Well, no, it's not confirmed but is traced from an original reissue

I used the original schematic as a way to check the main signal path. They have 'upgraded' the unit I guess.

Digitech got back at me; it has to have such a low output!!
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Post by zelasa »

Bernardduur, thank you!

I was looking at the Schematics, after reading this description at Digitech Manual:

"8. OUTPUT - connect to the next pedal input or to the input of your amplifier. This output allows you to route a dry unprocessed signal (Ring) and processed signal (Tip) to an amplifier and other effects simultaneously via TRS ‘Y’ cable.

Tip = Octave+Sub
Ring = Dry
Sleeve = Ground"

I understand that on the "Tip" of the connector, when the Switch is in the "Bypass" position, we have the Signal direct from the instrument, without the buffer (True Bypass). Or if the switch is "ON" we have the effect. But in the "Ring" of the connector we have always the unprocessed signal (without effect) but buffered (as we can see in the schematics also).

The last thing, and it is the reason of my question about the schematics, is that in the Schematics you posted the position of the Switch that connects the IC1a or the R38 to C2 looks like it is inverted in your schematics if we consider that the "actual" position of the switch is in the Bypass mode (as show by the switch position in the output and LED).

I attached the manual:
MeatboxManual_original.pdf
Meatbox Reissue Manual
(235.27 KiB) Downloaded 215 times
I am trying to buy one of these Reissue version!

Kind Regards!

Luis

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Post by DavidRavenMoon »

I had an original one I bought new for like $19 or something back in the early 90s... It was a closeout. It wasn't a very good sounding pedal. I took it apart to try and brighten up the sub-octave, and never ended up putting it back together. lol I'm not even sure what happened to it. The originals go for a lot of money these days. But it was pretty awful really.
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Post by Bernardduur »

zelasa wrote:Bernardduur, thank you!

I was looking at the Schematics, after reading this description at Digitech Manual:

"8. OUTPUT - connect to the next pedal input or to the input of your amplifier. This output allows you to route a dry unprocessed signal (Ring) and processed signal (Tip) to an amplifier and other effects simultaneously via TRS ‘Y’ cable.

Tip = Octave+Sub
Ring = Dry
Sleeve = Ground"

I understand that on the "Tip" of the connector, when the Switch is in the "Bypass" position, we have the Signal direct from the instrument, without the buffer (True Bypass). Or if the switch is "ON" we have the effect. But in the "Ring" of the connector we have always the unprocessed signal (without effect) but buffered (as we can see in the schematics also).

The last thing, and it is the reason of my question about the schematics, is that in the Schematics you posted the position of the Switch that connects the IC1a or the R38 to C2 looks like it is inverted in your schematics if we consider that the "actual" position of the switch is in the Bypass mode (as show by the switch position in the output and LED).

I attached the manual:
MeatboxManual_original.pdf
I am trying to buy one of these Reissue version!

Kind Regards!

Luis
You are right; part of the switch is in bypass setting, the other one in effect setting; sorry, missed that!
'No more....... loud music.......'
Follow my love for pedals and amps on https://bernardduur.blogspot.com and https://www.instagram.com/bernardduur1

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Post by drd »

Hi All,

Resurrecting this old thread... I'm trying to get this cracked. I have mailed Digitech, but the factory schematic of the reissue is not available for end users yet. Checked Bernarduur's schematic against the old version's factory schematic, and it is pretty much the same except for the flip-flop and the extra jfets for the switching. I tried to figure out the cap values, and most of them were easy based on the old version's values, but with the input cap and especially with the two caps at the end I'm puzzled. Could anyone maybe help with that? I could then create the PCB layout for this one.

Thanks!
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DOD Meatbox Reissue
DOD Meatbox Reissue

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Post by 9 volt »

Hi all, I have an issue with my fx32 meat box. The bypass signal works with battery but not with a power supply…… just wondered if anyone has any thoughts on this? Thanks

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