Ceriatone British Style Plexi 20

[67plexi]

I built a few Dumbelators you can adjust the input and output effects loop levels plus a extra master volume
you can get a cranked amp sound at bedroom levels

 

[DirtySteve]

Did you ask Nik about putting in an input that is jumper'd already? I forgot to ask you before, but that would be handy.

With a good buzz last night I emailed Nik and asked him about it. He said, "why would you want to limit yourself like that?". I have to agree, I don't think that's something I want.

 

[Ampeq]

With a good buzz last night I emailed Nik and asked him about it. He said, "why would you want to limit yourself like that?". I have to agree, I don't think that's something I want.

Don’t know what he means by “limit”, I have seen them on other 4 holer’s. They just put in another input that IS already jumper’d, a 5th hole. I think you can also still use those mini cords to jump as well. Should be just a cleaner way of doing it.

 

[XTRXTR]

Don’t know what he means by “limit”

Input resistance, the grid leaks parallel, likely guess. Because you can jumper Bright to Normal the actual guitar input you use will make a difference.

Jumpered: Then the guitar sees half the impedance and the channel it is plugged into (Bright v Normal) varies its output to the corresponding Volume thus I would think one channel becomes more dominant and the volumes vary the tone in a different way than the other config.

In other words you have four possibilities: Jumpered Bright, Jumpered Normal, Not-Jumpered Bright and Not-Jumpered Normal
Five: You can also have another person plug into the amp or add a looping song you want to practice with on one input while you use the other
Six: With another person playing in the other channel you can still add a looper.
Seven: two other mates playing with you and a looper using all four input jacks.

The pwner rules!!! lol
I actually did the classic fat finger! OMG

Perhaps Nik was thinking similarly. Doing an internal jumper only saves a patch cable, and if switched ON (assuming after the grid leaks) you parallel all inputs so it limits to all input parallel impedance. There may be other internal switch configs too but it still boils down to limiting the designed inputs from what they are to something less.

 

[syscokid]

Seven: two other mates playing with you and a looper using all four input jacks.

This must have something to do with being in an orgy…

 

[Ampeq]

This must have something to do with being in an orgy…

Man I hope so.

 

[Ampeq]

Input resistance, the grid leaks parallel, likely guess. Because you can jumper Bright to Normal the actual guitar input you use will make a difference.

Jumpered: Then the guitar sees half the impedance and the channel it is plugged into (Bright v Normal) varies its output to the corresponding Volume thus I would think one channel becomes more dominant and the volumes vary the tone in a different way than the other config.

In other words you have four possibilities: Jumpered Bright, Jumpered Normal, Not-Jumpered Bright and Not-Jumpered Normal
Five: You can also have another person plug into the amp or add a looping song you want to practice with on one input while you use the other
Six: With another person playing in the other channel you can still add a looper.
Seven: two other mates playing with you and a looper using all four input jacks.

The pwner rules!!! lol
I actually did the classic fat finger! OMG

Perhaps Nik was thinking similarly. Doing an internal jumper only saves a patch cable, and if switched ON (assuming after the grid leaks) you parallel all inputs so it limits to all input parallel impedance. There may be other internal switch configs too but it still boils down to limiting the designed inputs from what they are to something less.

OK, so yeah.... I can see.... aaaa ......if you ...., huh?

 

[Ampeq]

That's a good idea. I've never really used an effects loop partly because of all the extra cables. I almost told him to leave it off, but I didn't because I might use it someday. I figured it would be better to have it and not need it, than to someday need it and not have it.

This is what I was talking about for the loop. Simple and works great.

 

[T-Rex]

A retired truck driver’s version:

Looking at the layout, this Fat switch adds a .68 cap that parallels V2A’s 820 ohm cathode resistor. IMO, a .68 cap at this location adds a bunch of gain to the mids and highs, and barely any increase to the lows. I’m actually surprised it’s labeled as a Fat switch instead of a Gain switch.

Split/Shared V1 Cathode switch: I think that when V1 shares its cathode circuit with both inputs, that both volume controls are interactive with each other even with only a single input being plugged into. When V1’s cathode circuit is split, that interactivity is eliminated unless jumper cables are used.

3-way NFB switch: The higher the resistance value is, the less negative feedback is in the output circuit. The three selectable values accordingly to the layout is 49K, 95K, and 127K. More NFB makes the amp sound smoother, cleaner, quieter, and tamer. Less NFB makes the amp more aggressive, gainier, and wilder. Plexi’s generally are loaded up with 47K’s, which is like middle-of-the-road for NFB control. JCM800 2204’s use a 100k NFB resistor. Some amps have no NFB, like some Fender Tweeds and Vox AC’s.

Well Put !