Metropoulos Forum

Hey guys I've been slowly collecting Nos parts for my 100 watt plexi build and I had a few questions about mods to make it sound as close to Late Jimi as possible.

I am using the stock CE filter caps, should I get F&T or ARS will that make a difference?
Jimi took his "favorite amp" and made it from a split cathode to a shared cathode correct on V1?

What other mods did he make to the part values of his 100 watt plexi if anybody knows that would be great

Thanks guys

I like the sozo royal personally

But they are 100uf and the schematic calls for 50uf filtering how would I wire them?

harkham, please, do you have some piher resistors ?

harkkam08 wrote:But they are 100uf and the schematic calls for 50uf filtering how would I wire them?

Well, as some of you may know, there are certain formulas we can use to calculate total capacitance or resistance.

For resistors in series, it's as simple as adding the values together. For resistors in parallel, the formula is as such:

1/Rt (Rt=total resistance)= 1/R1 + 1/R2 + 1/R3.... etc. In essence, you take all you values, invert them, add them together, then invert your answer to come up with total resistance.

Example, 2 16 ohm speakers in parallel.

1/Rt= 1/16+ 1/16
= 1/8
Rt= 8 ohm

With Capacitors, you do the opposite to what you would do when adding resistors. If the capacitors are in parallel, you add the values together. Ex: 16 uf in parallel with 16 uf, the total value is now 32 uf.

Then is the caps are in series, you would use a similar method of inverting, as you did for finding paralleled resistor values, so find series capacitor value.

In your case, you want to use 100 uf capacitors for come up with a total capacitance of 50 uf.

This is your formula for series caps: 1/Ct (total capacitance)= 1/C1+1/C2+1/C3

Herego:

1/Ct= 1/100+1/100
= 2/100
=1/50
You then invert this answer (to the power of -1 on a scientific calculator) to find you series capacitance.

Ct= 50 uf when you put two 100 uf capacitors in series.

I figured I'd give you the shebang rather than just an answer, so you could sorta see how you figure it out.

Cheers,

Travis

Xplorer wrote:harkham, please, do you have some piher resistors ?

Hey Xplorer, I ordered some from ebay but they havent come in yet. When I get them I'll let you know maybe we can trade bcuz i got a few extra.


And thx omgtheykilledkenny I decided to run it stock 69 spec and see what that sounds like first.

Are there any part value mods that I should make to give it more of a jimi feel. I want the woodstock, BOG, Berkeley vibe, Royal albert hall

thanks !
i'll see what i'll get me too. i might need 2x 1,5k , 1x 15k and 1x 150k.
check the el34/6550 thread in the end for your quest.