freestompboxes.org

Did anyone ever made a single version, with only the crunch mode, and running a 9v?? Like the new plexitone single.

Roast7 wrote:It was interesting someone knew the layout for the crunch mode, to make a single Plexi

To get into the "crunch mode", just dial the gain pot lower

Not joking here, the crunch mode really is just less gain.

I know man: D
Madbean seems to develop a single plexi
But he liked to pick on this scheme plexi, and just build crunch mode.
like the original, using a Charge Pump to pass from 9v to 12v

Anyone who can help??

Or the new scheme Plexitone Single (that would be nice)

I have my updated layout pretty much done; just need to give it another lookover and then output it to a PDF.
The parts values match my 2011-dated Plexitone and includes Madbean's charge pump section that you can use either the LT1054 or the MAX1044(sp?) chip. (Just need to jumper two pads to use the MAX1044 at 9V). Buffered bypass and it sounds fine (no tone/signal loss). Extremely quiet and no popping on the footswitches.

I built my PT with a 50K Crunch pot and a 250K High Gain pot. This is much lower overall than the stock PT, but gives some better OD range. I typically had the 100K pot on my stock PT at around 9 or 10 o'clock mose of the time, and the High Gain around noon. The other values are a good fit; with the lower gain, the 2.2uF cap on the LEDs is pretty good, but on the stock PT (at higher gain), it's a bit too much.

I'll see about posting these files in the next day or so.

Harold wrote:I built my Plexitone yesterday ... a few remarks:
* The bypass really suffers from the 330pF to ground (C7) in the input buffer.
* Without C7, the input oscillates when not connected.
* The boost only adds volume, not "character".
* 1M gain is way over the top.
* The tone-knob is nice and has quite a range.
* The pedal has either a bass and treble boost, or lacks mids ... it's way too scooped right now.
* Nice and gritty overdrive, great note-separation, attack and definition!

Schematic used: http://i51.tinypic.com/otlu7l.gif

Mods performed:
* Removed the (dull) boost function.
* True bypass! C7 ruined the original bypass. This also cleans up the wiring quite a bit!
* No gain selection and a 100k audio pot which has more than enough gain. 250k might be more versatile, but I couldn't find one

Experiments planned:
* R7: This supposedly alters the whole feel of the drive. 1K potentiometer?
* C13: Maybe there's a "better" tone frequency to be found!
* C15: Raising it should provide a mid-like boost. Sabrotone uses 150pF and I read someone even used 4.7nF instead of 22pF.
* Expose the clipping LEDs, they light up pretty bright!
* Use a B enclosure since I don't use the boost or gain footswitches.


First impression was pretty decent though , but we're not there yet!

Harold What was the scheme that you used? the link is no longer online: (
I want quite a version of this pedal but only crunch mode.

Original Plexituna


If I want to build only the Crunch mode, just need this part of the scheme??


Then use a voltage regulator 9v to 12v right?

No, you'd need that section at the end, too, minus the boost pot.
I've been dragging my feet with other stuff, but will do my best to get the PDF posted today. With this layout, you can build it any of these ways:

Single (crunch or high gain)
Single w/boost
Dual drive (crunch and high gain) without boost
or stock (dual drive w/boost)

There are jumpers/connections to leave out for each config. I built mine as a dual drive without boost (never really used it, but if you had two lower gain pots for crunch/high-gain, it might be a good 3rd option).

FWIW, the only value differences between the Plexituna schem and the stock 2011 PT I have (dated on the board) are:
- uses 3 LEDs instead of 4
- C7 is 22pF
- C10 is 47pF
- R7 is 22K
- there is a 2.2uF 100V electrolytic cap going from pin 3 of the LF347 to the on/off footswitch, presumably to remove bleed-thru to bypass and/or any popping.

This will all be reflected in the new build doc.

I will say that my DIY PT build is not as bright as the stock one I have; on the tone control, 9 or 10 o'clock on the stock one is about noon on the DIY. The part values are the same, but I'm using Cornell Dubilier (sp?) film caps (Skreddy once said that he found these a workable replacement for his builds) for the larger values.
I'm currently using 50K and 250K for the Crunch and High Gain (respectively), per Madbean's suggestion for this circuit. The Crunch has a much wider range of gain than before (allowing for several sweet spots), but I typically find myself at 2 o'clock or higher; the 250K is noticeably higher gain (and compression) when you hit it, but not overwhelmingly so. I never really had a problem with the stock gain values on the PT (I had mine dialed in pretty happily for me), so I COULD probably go with 100K/250K or even 100K/500K if this were my only Marshall-esque pedal; I built this one to use as my lower-gain/classic Marshall box to compliment my dual-gain BSIAB II that I use for hot-rodded sounds.

Like this??

Bingo

I have to also include that my layout is the buffered version, not true bypass. I'm to the point that I only use true bypass about half the time.
As long as it's not a noticeable tone loss, I'm all about buffers since I have so many pedals on my board.

I'm doing separate PDFs for each config so it'll be easier to follow based on the one you want to use.
Working on the full/stock version now.....

Ok, here you go:

New PCB to use with all configs below - ready-to-print, actual size for image transfer to PNP Blue, etc
http://www.4thlevelmedia.com/smallpics/ ... ne_PCB.pdf

PlexyTone with dual gain and boost (like stock PT)
http://www.4thlevelmedia.com/smallpics/ ... _Stock.pdf

PlexyTone with dual gain, no boost
http://www.4thlevelmedia.com/smallpics/ ... oBoost.pdf

PlexyTone with single gain and boost
http://www.4thlevelmedia.com/smallpics/ ... eBoost.pdf

PlexyTone with single gain, no boost
http://www.4thlevelmedia.com/smallpics/ ... Single.pdf

As usual, please inform me of any errata in the data above, as well as any questions. I'm powering mine with a BBE SupaCharger and using the LT1054 charge pump.

Thanks,
Buck

Very cool man
What measures the pcb?

So if the schema (single) is the last to put here so it must be correct, the "Vero" that I did today.
Is not checked, but it seems correct

My PCB is about 2.4" x 1.65".
Not sure on your vero - just remember the parts values I mentioned above, verified in the 2011 version.

Ok, but if so, the values ​​we have is the, PT version 3 (plexituna)
The scheme plexituna represents models of which year?

Roast7 wrote:Ok, but if so, the values ​​we have is the, PT version 3 (plexituna)
The scheme plexituna represents models of which year?

I don't know which version is from what year, but my suggestion is just to play with the values in question, based on the ones I provided and the ones circled in red on the Plexituna schem.
Three LEDs will clip asymmetrically, where four will clip symmetrically. I love the sound of my 2011 PT, so I used those values in my layout.

This is nice
What is the schematic, of the layout that you had done?

It's the same as the Plexituna, for the most part. A few values are different (that I've mentioned before), but there is the electrolytic cap on the bypass (see my parts layouts); that's missing on the Plexituna.

I understand
So your model should be like this, right?




He says in the corner, year 2001 or 2004
The Plexitone of 4 leds clipping is the older version, or younger?

I really liked the layout of your pcb.
And sound? when you record a sample of him?

bucksears Already built your layout?
I'm fond of of building, or the Crunch and Hi-gain, or Crunch only.

Roast7 wrote:bucksears Already built your layout?
I'm fond of of building, or the Crunch and Hi-gain, or Crunch only.

Haven't built it yet, but the differences are not that great - just a few minor tweaks to the layout.

Anybody know if the tone control is just the 5K pot and the .068uF cap, or is the 22K resistor in parallel part of it too?

I'm looking whipping up a new layout that incorporates Runoffgroove 'Tonemender' EQ circuit; this would give the Plexitone/AC-Tone a 3-band EQ if successful.
Thanks!

- Buck