D*A*M - Meathead  [traced]

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Visualdistortion
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Post by Visualdistortion »

With a 3PDT, I can switch just between 2 caps? (ON/ON or ON/OFF/ON), with a 4PDT I can switch instantanely between 2 duos. Or with a rotary switch 2x6, I can switch betwen the 3 duos but I can't mix them.
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Post by beedotman »

Visualdistortion wrote:With a 3PDT, I can switch just between 2 caps? (ON/ON or ON/OFF/ON), with a 4PDT I can switch instantanely between 2 duos. Or with a rotary switch 2x6, I can switch betwen the 3 duos but I can't mix them.
Sorry, I'm wrongly desrcibed it... You will need ON/OFF/ON switch and do similar trick as used for example in beano boost - middle position - lowest capacitor value, in other positions will be added another capacitors in parallel so total capacitance will be bigger:
For example for input capacitor switching

Left position 1uF+22nF
Middle position 22nF
Right position 47nF+22nF (or 22nF/27nF +22nF for more exact value around 47nF)

or something like this - maybe rotary switch will be better solution.

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Post by Visualdistortion »

Okay so for Input switch between 1uF, 47nf, 22nF, I must use 820nF+150nF, 22nF, 27nF
Output )switch between 100nF, 22nF, 10nF, I must use 22nF+68nF, 10nF, 12nF

Completely stupid things but the values a goods.

Other question the meathead I've made sound great (22nF, 22nf) on a lower quality amp (crate 15W) but in my Orange TH30, it produce a very big incotrolable hiss (gain hiss)... is it because my BC182L have an high hfe? or it's the 22nF combo.

Thanks
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Post by beedotman »

Visualdistortion wrote:Okay so for Input switch between 1uF, 47nf, 22nF, I must use 820nF+150nF, 22nF, 27nF
Output )switch between 100nF, 22nF, 10nF, I must use 22nF+68nF, 10nF, 12nF

Completely stupid things but the values a goods.

Other question the meathead I've made sound great (22nF, 22nf) on a lower quality amp (crate 15W) but in my Orange TH30, it produce a very big incotrolable hiss (gain hiss)... is it because my BC182L have an high hfe? or it's the 22nF combo.

Thanks
For input I would use 22nf as a main capacitor in middle position and another 27nf (so 49nf in total with paralleled 27nf and 22nf) and 1uf (1.22uf in total with paralleled 1uf and 22nf).
For output - 10nf in middle position and 10nf +100nF - so values would be 20nf (two 10nf in parallel) and 110nf (10nf and 100nf in parallel).
There's no need to stick to exact values...

Meathead is a gainy monster, so there will be some hiss on higher gain settings - I could try to use shieleded input and output wires, low nosie resistors 1% metal film resistors and transistor selection is important, too - try to find pair with lower hiss. I think that Q1 should be under 160hfe and Q2 below 200hfe or something.

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Post by monkeyxx »

I absolutely would use 22n as the default/lowest cap value

the 10n value that's floating around in a lot of layouts is way too light in the bass for my taste, although I guess it's fun to shred around for a minute like some kind of hair metal guy and then frown at yourself and switch back to the good deep heavy sound. 47n is a good balanced all around sound for me.

the Deluxe is a great one to build as well because of the knob that controls the bass response, it's pretty practical, sturdier than a toggle switch, can get even darker

I had good luck experimenting with transistors. In my regular one knob I used BC182L in Q2, 2N3904 in Q1 with a switch to 2N5306, gets "grunty" sounding and up high on the neck it does this weird octave down pitch shift intermittently, which is cool for solos.

In my Deluxe 3 knob I started with 2N3904/BC182L and it was a little brighter and shreddier, distortiony sounding than the one knob, then I put a BC107C in Q1 and it got that familiar dark heavy tone... I'll be adding a switch to go between the two.

D. Main has gone through various transistors in his builds over the years, including 2N3904, BC182L, BC107, and BC108...picked this up from gut shots and info at the DAM forum. but in/out cap selection is just as important for the tone.

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Post by hiorgos »

I finished mine today, and I shamelessly can say I'm so proud! :lol:

Had a lot of problems, but it finally worked! Used a tagboard for it, well some kind of "custom" board.. after a regular approach didn't work for me. And put a filter on the input. A 100kA pot to move between 0.1uf and 0.01uf to Q1 base, quite bright actually on this last cap, but useful I think. It doesn't change the tone, just the amount of "meat" you put on the grill, I would say.

Also, replaced the BC182L for a BC109, and it sounds good.

0.022uf for the last cap.

Also, plan twice when drilling the case, you might run out of space so easily when using a 1550B.. (noob here)

Overall the pedal sounds fantastic! I just need to re-solder the 9v wire, and it will be done. Can't wait to play it!

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Post by beedotman »

hiorgos wrote:I finished mine today, and I shamelessly can say I'm so proud! :lol:

0.022uf for the last cap.

Congrats! :thumbsup
Try to change output cap to 0.1uF for more bottom.
I personally prefers higher value than 22nF.

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Post by hiorgos »

beedotman wrote:
hiorgos wrote:I finished mine today, and I shamelessly can say I'm so proud! :lol:

0.022uf for the last cap.

Congrats! :thumbsup
Try to change output cap to 0.1uF for more bottom.
I personally prefers higher value than 22nF.
Yap, thanks!

I tried several caps both for first and last caps, ended up liking it this way. I really like the filter knob, at 0.1uf adds a nice punchy tone, that can be gradually cut to 0.01, for solos or playing some riffs with a "bassy" bass player. I think it's enough to call it done. :)

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Post by eoe »

Finished mine a while ago. I used the Heat of the meat - verolayout by Tonmann. I also added a DPDT - switch to change between the regular and dark versions of the pedal. The switch changes the input and output caps, 10nF in and 22nF out for regular and 470nF in and 100nF out for dark.

The sound worked fine for me, though the dark version was maybe a little too muddy for my setup. This was my first build ever and the quality of my soldering was quite bad, so I had to fix cold solders several times. After a year of playing the pedal once again turned into a squealing noise generator, and I don´t think that if I have the perseverance to repair it anymore. Lesson learned: I really need to teach myself how to solder properly. :blackeye I might give the Deluxe M-25 a go at some point.
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Post by beedotman »

eoe wrote: I also added a DPDT - switch to change between the regular and dark versions of the pedal. The switch changes the input and output caps, 10nF in and 22nF out for regular and 470nF in and 100nF out for dark.
Firs "Regular" version had 22nf on input and output, later "regular" M-13 version had 47nF input and 100nF output caps.

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Post by beedotman »

Nice finish BTW :thumbsup :)

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Post by Visualdistortion »

eoe wrote:Finished mine a while ago. I used the Heat of the meat - verolayout by Tonmann. I also added a DPDT - switch to change between the regular and dark versions of the pedal. The switch changes the input and output caps, 10nF in and 22nF out for regular and 470nF in and 100nF out for dark.

The sound worked fine for me, though the dark version was maybe a little too muddy for my setup. This was my first build ever and the quality of my soldering was quite bad, so I had to fix cold solders several times. After a year of playing the pedal once again turned into a squealing noise generator, and I don´t think that if I have the perseverance to repair it anymore. Lesson learned: I really need to teach myself how to solder properly. :blackeye I might give the Deluxe M-25 a go at some point.
How the switch is wired? thanks
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French... sorry ;)

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Post by monkeyxx »

thought you all might get a kick out of this...

modified a real DAM meathead, on the inside it's called the "mid hump" model or something on the inscription... same as the common vero layouts going around

modified it with a "dark" switch... here's pictures

Image
Image
Image

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Post by eoe »

beedotman wrote: Firs "Regular" version had 22nf on input and output, later "regular" M-13 version had 47nF input and 100nF output caps.
Ok, thanks for pointing that out. I don´t own any original meatheads, so I´m not sure which could be best called regular. There are different values between different layouts. I think the builder of these pedals changed the values from the earliest versions.
beedotman wrote:Nice finish BTW :thumbsup :)
Thanks, I think I focused too much on the outsides of the pedal rather than insides :)
Visualdistortion wrote:How the switch is wired? thanks
I added the wiring of the switch as an attachment. I´m not particularly experienced with this stuff, but that´s how I got it working anyway. As beedotman mentioned, there are different values for the capacitances, so choose ones depending on your own judgement.
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Post by beedotman »

it's DIY modification or done by DAM?
monkeyxx wrote:thought you all might get a kick out of this...

modified a real DAM meathead, on the inside it's called the "mid hump" model or something on the inscription... same as the common vero layouts going around

modified it with a "dark" switch... here's pictures

Image

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Post by phibes »

Damn, the resale just dived on that one....
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Post by lofi73 »

IvIark wrote: Image
These boards look great.Scuse my noobism but is it vero,pad per hole or...?.

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Post by IvIark »

Yes it's vero. This is the most up to date version of that layout if you want to build one:

http://tagboardeffects.blogspot.com/201 ... thead.html
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Post by lofi73 »

IvIark wrote:Yes it's vero. This is the most up to date version of that layout if you want to build one:

http://tagboardeffects.blogspot.com/201 ... thead.html
Yep.I already did...And thanks for your help and info there :thumbsup .There are obvious similarities between your layout and the ones on the photo.A tranny has been moved and some resistors too...Does your update have an advantage in form of shorter traces or??.(Excusing my dumb questions.I have´nt layed out anything much but a LPB yet. [smilie=a_biggrin.gif] ).

I don´t own an original Meathead (Or any D*A*M-pedal) myself..Are they also made on vero?.(Vero as in coppertraced board stripboard)

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Post by IvIark »

Those 4 boards were made from an earlier version of my layout. Can't remember why I changed it, probably because I thought the new way looked cooler! :lol: And yes, every original Meathead I've seen has been made on vero.
"If anyone is a 'genius' for putting jacks in such a pedal in the only spot where they could physically fit, then I assume I too am a genius for correctly inserting my legs into my pants this morning." - candletears7 - TGP

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