El509 Pse

[Hojvaelde]

Hello

As You all know, am I looking for a 20W SE amplifier.

Some have told me a EL509 in enhanced triode mode is the amplifier with a fine sound.

I found the SYNOLA 509 ( based on a EAR 859 ) but only 10 watt.

My question is:

I set the DC current to 90 mA/EL509

OPT with RA at 1k8 - 2k.

Separate bias pot meter.

Can the driver tube drive 2 EL509 tubes?

Benny

[Tubes4e4]

Hi Benny,

I found the SYNOLA 509 ( based on a EAR 859 ) but only 10 watt.

I bet not even Mr. Seyer would claim that. The EAR859 is quite different in many ways.

Can the driver tube drive 2 EL509 tubes?

Certainly not. With DC coupled screen drive, when the output stage plate swings quite low (which it must to get some effiency), the screen will draw a rapidly soaring ammount of current the driver must be able to deliver (at low distortion). What can a pair of ECC82 sections deliver at that voltage? Maybe 20mA peak, or something, with gross distortion.

With the considerably smaller EL36 used with screen drive, I measured up to 20mA peak screen currents for comparable audio load situations already, see here.

I bet the driver is already at the edge feeding one EL509 screen grid, not to talk of two.

If you want to feed two screen grids this way, at least use something in the range of trioded EL84 or EL83 instead.

Nota bene, have a look at this one, too. But don´t trust the EL509 screen drive curves shown there. I don´t know what he is showing there, but for lower plate voltages it has nothing to do with the reality of about half a dozen of EL509/PL509 from 3 different makers (and construction) I measured myself. The curves looked all as gross as the screen driven EL36 shown above.

Tom

[josepmaria78]

ESCUSE-ME:

Me gusta este esquema de amplificador , pero yo por mi parte tambien necesito mas potencia de salida.
Lo ideal segun informacion de USA. de Petersen & Sinclair, es que un amplificador para uso domestico a tubes, necesita de 15 a 20 watts.
Pienso que con unpar de EL.509 en paralelo, se pueden obtener los 15 a 20 watts. de audiio.
Tambien debo decir que nunca he probado de construir un amplificador SE. con estos tipos de circuito.
Me gustaria poder realizarlo con su ayuda. Gracias. Espero su respuesta
por correo.

The ingles it is very dificult for me. Sorry.

[SY]

Originally Posted by josepmaria78

The ingles it is very dificult for me. Sorry.

Nonetheless, the forum has rules about posting in English. You can try using an online translator.

Google Translate of your post:
I like this scheme amplifier, but I for one also needs more power output.
Ideally, according to information from USA. Petersen & Sinclair, is an amplifier for home use with tubes, you need 15 to 20 watts.
I think with EL.509 unpar of parallel, you can get 15 to 20 watts. of AUDiiO.
I should also say I've never tried to build a SE amplifier. with these types of circuit.
I wish I could do with your help. Thanks. I await your response
by mail.