Stromberg Carlson no.19 model Pa head conversion output issues

[Oregonblues]

Hey everyone, I’m in the midst of trying to convert a old stromberg Carlson no.19 model PA to guitar/bass,

I’m passing signal fine through the amp but to me it seems the output volume is severely lacking, it’s just not loud at all and you can fairly easily talk over the amp when at max volume, I’m assuming there is just something I’m not quite seeing to get it to open it up a bit more, I can provide the original schematic but I’ve changed some values to more what you’d see in fenders

Currently here is the Pinout voltages with no signal, any ideas would be greatly appreciated, I’ve swapped the tubes with no improvement

1st tube - 6sj7
1: ground
2: 4.7 vdc heater
3: .746 vdc grid 3
4: -.3mv dc grid 1
5: 0.0 cathode
6: 23.62vdc grid 2
7: 4.8vdc heater
8: 145.7vdc plate

2nd tube 6sf5
1: ground
2: 1.06vdc
3: -3.5mv dc
4: empty
5: 113vdc plate
6: empty
7: 4.8vdc heater
8: 4.8vdc heater

3rd tube/phase inverter 6n7
1: ground
2: 4.5vdc heater
3: 115.2 vac plate
4: 0
5: bouncing from -1.5 to 5mvdc
6:128.5 vdc
7: 4.5vdc heater
8: 3.16vdc cathode

6l6gc tubes at 42ma on bias probe meter

4th tube 6l6gc
1: ground
2: 4.5vdc heater
3: 402vdc
4: 311.5vdc
5:30ish mv dc
6:none
7: 4.5vdc heater
8: 23.9vdc

5th tube 6l6gc
1: ground
2: 4.45vdc heater
3: 402vdc
4: 311.5vdc
5: 31ishmv dc
6: none
7: 4.5vdc heater
8: 23.9v

6th tube rectifier gz34
2: 408v

[Stevem]

Your heater voltage on tubes 1 thru 5 should be no less then 6.1 volts and no more then 6.9.

With that low heater voltage you have no signal gain taking place.

Please post up the schematic.

[Oregonblues]

Here should be the original schematic

IMG_6750.jpeg

[Oregonblues]

I’ve swapped some values closer to old fender specs but brought the phase inverter back to stock schematic values