lumox0013 wrote:I have built many a spitfire now each one sounds different because I use mostly donor amps for trannys but one thing I find effects all of them greatly is speaker selection. what type of speakers are you running?
Right now I'm using a two 10 open back cab with one Eminence Ramrod and and one Eminence Copperhead, one speaker supposedly British and the other American. The speakers are still breaking in at this point with under 10 hours of playing time.
Structo wrote:
Simply, you replace the input side 1M resistor on the phase inverter with a 1 Meg audio taper pot.
Here is a schematic of that and of the double boot strap MV..
Ok well here's where I hopefully don't appear like a total newbie and ask a dumb question. I have the 1 Meg audio pot if I reuse the Master volume pot but I'm a little confused about where to connect it in the circuit with the layout I have since there are two inputs and two 1 M resistors one on each side of the PI tube. Do I just replace one of those 1 M resistors and put the pot in place of it and does it matter which side I replace?
Yes, it matters.
The schematic I posted has the triodes of the tubes wired where the second triode is wired first. This is an old school thing because it is thought it is quieter to wire miniature tubes this way.
It depends how you have your sockets wired but if yours is exactly like the layout, you would remove the 1M that goes to pin 2 on the phase inverter.
Remove that resistor and then connect the 1M pot to those two turrets.
While looking at the back of the pot, the right lug would go to the turret with the .01uf cap, the middle or wiper lug would go to pin 2 and the left hand lug would go to the other turret which joins the other resistors.
If for some reason the rotation is backwards, just reverse the two outside wires on the pot.
if you have acess to a 12" celetion 65,75 or 100 t or h give a try you might like ,the highs will jump out at you more with a more defined low end better balance.
