Plexizer, does the tone stack do much?

[caspercody]

I made the Plexizer, and it works. But the tone stack, and presence controls do not seem to do much.

For those that have made this, does your controls work? Does it change the tone alot or alittle?

If I do have a bad component in my tone stack, what is the best way to determine which part it is?

Thanks
Rob

[caspercody]

Please, did anybody build this?

[BAARON]

Which schematic/layout did you follow?  I haven't built this myself, but I glanced at the original schematic.  I don't know how much the presence control would do, but the tonestack itself is a standard Marshall TMB tonestack, so its effect should be as noticeable as the tone controls on a Marshall amp (as long as you keep in mind that it comes after the distortion, and not before).

From experience, I've found that if you're wiring up a Marshall or Fender style tonestack and you miss a connection or put a wire to the wrong spot on One control, it can mess up all three.  For example: how many lugs are you using on your bass pot, and what are they connected to?  If you've got the bass pot wrong, nothing else will work properly.

I'd check the wiring and compare it to another schematic of the Marshall TMB tonestack.

[caspercody]

I used Mojotrons schematic, and Bucksears pcb layout.

Thanks, I will first look at the wiring to the pots.

When looking at the schematic of the ts, is the pin out for the middle pot (from top to bottom) 3,2,1? Or is it a opposite pin layout (than the treble and bass) since the arrow (wiper) is on the other side?

Thanks

[petemoore]

  Pretty sure, but you can verify what you've got and take a look at interactive chart/graphics...what kind of attenuations your Marshall and other types of tonestacks do while verifying your schematic is Marshall TS: Duncans Tonestack Calculator, invalueable too. This tool lets you judge well from views of the Frequency / loudness graphic display while twiddleing the toneknobs of your favorite [helps you choose your] TS.
 Because I recall the name I'll say I think the schematic is veryfied and good.
 If that's the case, built as shown it will work about the same as the enxt one built as shown, all Marshall tonestack work/sounding.
 Miss one or overconnect one node, the outcome is the same case will all audio electronics which lead to 'why doens't it work?'.
 At this point your best bet is to develop debugging chops, the best page for you to study and apply to your right now is the "Debugging" sticky.
 This read may just open the book to the first page, but prompts the reader into further material study to better understand. Google terms and phrases for best results. Also read at "GEO" and work to find what helps explain what's there.
 The bias voltage and basic wiring challenges be adressed for any new build, especailly a one-off even if it seems like it's working...I mean, a tonestack either works or seems like it isn't working, but transistor biases in Fuzzes and other can be pressed to sound pretty good when badly misbiased, unless you miss  something you'd never know what i's 'supposed' to sound like.
 Debugging sticky is Standard "E-Wushu" for problem challengers.
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[BAARON]

I used Mojotrons schematic, and Bucksears pcb layout.

Thanks, I will first look at the wiring to the pots.

When looking at the schematic of the ts, is the pin out for the middle pot (from top to bottom) 3,2,1? Or is it a opposite pin layout (than the treble and bass) since the arrow (wiper) is on the other side?

Thanks

I'm pretty sure the arrow is just on that side to make it more convenient to draw.  If you wire up your mid control backwards, all that'll happen is it'll have to be turned in the opposite direction (and then you'll realize that it's backwards, because your ears will tell you).  It wouldn't shut down the tonestack entirely.

[mojotron]

I made the Plexizer, and it works. But the tone stack, and presence controls do not seem to do much.

For those that have made this, does your controls work? Does it change the tone alot or alittle?

If I do have a bad component in my tone stack, what is the best way to determine which part it is?

Thanks
Rob

Yep, the tone controls work, but the presence control is not all that strong - I think that could be replaced with a switch to go all on and all off: Even so the effect of the presence control is not all that great since there is a ton of high-end there to work with already. The key, I think, on those kinds of circuits - and there are a bunch - is to get the JFETs biased to get the highest output - then everything seemed to work for me. Also, if I was to do some redesign on that - and it's pretty much a ROG Thunder Chief with some minor tweaks plus tonestack so all those ROG notes there might apply too - what I would do is to use bigger  miller caps - like 200-220pF - especially in the 2nd stage. That would fill-out the lowend better to allow the tonestack to have a little more meat to grind.

But, I do like the sound the way it's drawn up - there's a specific sound that it does very well due to C6 and the tonestack - kind of an extra nasty bite in the upper mids. I was my main distortion pedal for a couple of years, that is until I got into the 'plug direct into the amp' phase I've been in for a while now 

[euronymous0001]

I made the Plexizer, and it works. But the tone stack, and presence controls do not seem to do much.

For those that have made this, does your controls work? Does it change the tone alot or alittle?

If I do have a bad component in my tone stack, what is the best way to determine which part it is?

Thanks
Rob

resurrecting an old thread 

my tonestack, a scaled down version of the stock version (x10 for the caps and x0.10 for the resistor and pots), also doesn't do much. did you ever manage to modify the TS wide wider range?

TIA

[Davelectro]

resurrecting an old thread 

my tonestack, a scaled down version of the stock version (x10 for the caps and x0.10 for the resistor and pots), also doesn't do much. did you ever manage to modify the TS wide wider range?

TIA

I'm afraid the marshall tone controls won't work too well in a 9v stompbox. The loss is too big even with a scaled down tonestack 'cause the signal entering the tonestack is not that strong after two jfet stages. IME, you'll get better results with higher voltage and/or mini booster stages.

[mojotron]

Ya - you can get rid of the presence and bass controls and just wire them to be full on. I use the mids and treb controls on mine quite a bit.