Series/parallel heaters?

[Smokebreak]

I've got a near bone stock '63 BF Deluxe Amp here, non reverb.
I only see fresh solder in a couple places. One is on the V1 pins. Pins 4 and 5 have been unsoldered from one another, and one leg of the filaments was taken off of pin 9 and moved to pin 5. So V1 was wired in series. Rest of the amp is in parallel, stock. What is the point of this?

[M Fowler]

For an EF86 tube perhaps?

[Smokebreak]

Well v1 and v2 tubes were missing when the amp came to me, but owner mentioned he had pulled them for another amp. I asked him but he didn't know what was originally in there when he got it. He was pulling V1 to get that 820r cathode flavor on the vib channel. The rest of the pins are untouched and circuit is the same, so I'm not really sure..

[Smokebreak]

Allright, from the input jack goes to pin 2 and off the volume pot goes to pin 7, as normal w/12ax7, but these are shields in an EF86 so I don't think that could be it?

[sluckey]

I've got a near bone stock '63 BF Deluxe Amp here, non reverb.
I only see fresh solder in a couple places. One is on the V1 pins. Pins 4 and 5 have been unsoldered from one another, and one leg of the filaments was taken off of pin 9 and moved to pin 5. So V1 was wired in series. Rest of the amp is in parallel, stock. What is the point of this?

Maybe he was going for some crazy EVH "brown" sound by running the filaments at reduced voltage?

[JazzGuitarGimp]

Yup, I was thinking the exact same thing as sluckey.

[gui_tarzan]

He'd be better off using a Marshall Plexi on a Variac, a "potted until it almost melts" PAF, a Charvel Strat body and neck and he may want to borrow Eddie's fingers to get that sound.

[LOUDthud]

There are some dual triodes that just need 6.3V on pins 4 and 5. Sometimes a shield is connected to pin 9. 6BK7, 6BX8, 6BZ7, 6BZ8, 6CG7 and a number of Russian tubes for which I have no data. Could be that someone wanted to try one of these tubes for some reason or another.

[Stevem]

It would sound far better to add another filter node for V1 and use a big resistor to run it at 90 to 105 volts on the plate with a ax7 wired for normal filaments
Then having a low heater voltage on a ax7!

[Smokebreak]

Also, pins 1 and 8 are tied together on the 6V6s(for metal shell 6V6?), and there are no 1K5s on the grids. Tail in PI is 27K, 100K PI plates, and grids tied together in tremolo circuit, so this is AA763