Tubes Home Theater 4+1

[pilovis]

I'm a little crazy and want to build a "4+1 Home Theater" with tubes, except DSP, obviously

The 5 channels amplifier will have the follwing characteristics:

Front channel: 15 W (push-pull of EL504, 2x EL504, 1xECC82, 1xECC83)
Side channels: 7+7 W (class A ultralinear with 2x807 and penthode driver with 2x6G6G)
Read channels: 5+5 W (class A ultralinear with 2x6L6G and triode driver with 1x6N2p)
Preamplifier: two stages per channel, preamplifier plus cathode follower or maybe SRPP (9xECC83)
Power supply: four indipendent stages (1x5X4G + 3x5Y3GT)

All the schematics are based on my projects I already built and tested, I am sure they work well.

I have all 20 tubes already availables:
1x 5Y3G Fivre, 1x 5Y3GT Sicte, 2x 6G6G RCA, 2x 6L6G Fivre, 1x 5X4G RCA, 2x ECC83 Brimar, 2x EL504 Philps, 1x5Y3GT RCA, 2x ECC82 Philips, 2x ECC83 Telefunken, 2x 6N2p, 2x 807 Zaerix

I will post schematics soon

 

[50AE]

Interesting project, but isn't it better to start with the output trannies instead of tubes? They should be the most important piece in the amplifier.

Good luck with the project! I will love to check it out frequently!

 

[pilovis]

Interesting project, but isn't it better to start with the output trannies instead of tubes. They should be the most important piece in the amplifier.

The output trannies are:

1 x 2k/8ohm push pull transformer (EL504)
2 x 5k/8ohm - 43% tap for ultralinear (807)
2 x 3.6k/8ohm - 43% tap for ultralinear (6L6G)

 

[pilovis]

Rear channels:

Class A ultralinear with a little negative feedback.

Tubes: 6L6G (2) & 6N2P (1)
Pout MAX: 5+5 W
Output Trasformers: 3.6K/8 ohm - 43% tap
Plate current of 6L6 = 44mA
Plate voltage of 6L6 = 240V
Cathode voltage of 6L6 = 18V (bias)
Screen grid voltage of 6L6 = 200V

 

[pilovis]

Side channels.

Class A ultralinear with no feedback and penthode driver .

I've just discovered there is an error on the schematic above, the supply voltage is indicated as 300 Vac, it should be changed to 300 Vcc.
Sorry for the mistake .

Tubes: 807 (2) & 6G6G (2)

Pout MAX: 7+7 W
Output Trasformers: 5K/8 ohm - 43% tap

Plate current of 807 = 50mA
Plate voltage of 807 = 290V
Cathode voltage of 807 = 17V (bias)
Screen grid voltage of 807 = 240V

Plate current of 6G6G = 2.9 mA
Plate voltage of 6G6G = 96V
Cathode voltage of 6G6G = 3.5V (bias)
Screen grid voltage of 6G6G = 55V

The 6G6G has a little filament current (0.15A) = lower HUM than a 6SN7 or ECC83 driver, it has a good gain in this configuration and cathode voltage as low as 3.5V = lower HUM again.
There is no need to use DC voltage for filaments, but it would help considering that filaments voltage is higher than cathode voltage (= no HUM at all).

 

[rongon]

Just curious... What are you using for the DSP, signal routing, volume control, etc? A "surround preamp" of some kind?