EL156 PP

[Tube747]

My brother suggested I join this forum about very technical tube stuff. I'm new to this forum. I never heard of anyone talk much on EL156 since it's quite popular in Japanese DIY Audio field.

I read its specification, it can run 450V for class A and class AB up to 800V.

It's a pentode, but can be run in triode for 500V. I see someone claimed a pair of these in PP capable for 150W!

Therefore, which way you prefer class A pentode or triode, or high power in class AB with much high operating voltage??

[multi]

Hi Tube747
I have just ordered some EL156 from China {octal socket}
Hope to use them as triodes at 470 volts. never used them before. I was worried 470 volts might be too high.
Phil

[hooman]

how about nos el156? any experience in sound different?

[Funker]

Originally Posted by Tube747

My brother suggested I join this forum about very technical tube stuff. I'm new to this forum. I never heard of anyone talk much on EL156 since it's quite popular in Japanese DIY Audio field.

I read its specification, it can run 450V for class A and class AB up to 800V.

It's a pentode, but can be run in triode for 500V. I see someone claimed a pair of these in PP capable for 150W!

Therefore, which way you prefer class A pentode or triode, or high power in class AB with much high operating voltage??

Hi ,
a pair EL156 can deliver 130W rms with 800V plate and 400V at the screens. Look at the spec sheet:


http://frank.pocnet.net/sheets/128/e/EL156.pdf



73
Wolfgang

[Kay Pirinha]

I'd be very cautious with these Chinese firecrackers which are sold as EL156's, especially if operation at plate voltage levels of 800 volts or even more are intended! Why? They are equipped with an international octal socket, sharing the pinout with EL34 or, very similar, 6L6, 6550, KT88 etc. The disadvantage of this layout, compared with the original Telefunken 10-pin socket, is that plate pin 3 is adjacent to heater pin 2, thus very often leading to arcing and burning the isolation of the socket and/or the base. Many of nowadays' production EL34's share this problem!

Best regards!

[7N7]

Originally Posted by Kay Pirinha

I'd be very cautious with these Chinese firecrackers which are sold as EL156's, especially if operation at plate voltage levels of 800 volts or even more are intended! Why? They are equipped with an international octal socket, sharing the pinout with EL34 or, very similar, 6L6, 6550, KT88 etc. The disadvantage of this layout, compared with the original Telefunken 10-pin socket, is that plate pin 3 is adjacent to heater pin 2, thus very often leading to arcing and burning the isolation of the socket and/or the base. Many of nowadays' production EL34's share this problem!

Best regards!

Yes good points,

I cut my teeth repairing music amplifiers - for guitars and so on, and had to replace several valve bases, these being octals for EL34s running at around 450V. The problem was of course tracking.

I was always amazed at Mullard's data offering 100W from a pair of EL34s in Class B, running at 800V; I suppose that Mullard had access to exceptionally good sockets - PTFE perhaps?

For high voltage stuff I am much happier to see the anode connection at the top of the valve where it rightly belongs!

Paul

[Kay Pirinha]

Exactly my thoughts, Paul !

That's why I love TV sweep power tubes. Or original TELEFUNKEN EL156s with their G10A/Stahl 10 sockets and their plate pin located far apart from any other one. Or cheap, reliable, beefy (but ugly) all-glass socket GU50s and solid ceramic bases they're sitting on.

Best regards!

[7N7]

Originally Posted by Kay Pirinha

Exactly my thoughts, Paul !

That's why I love TV sweep power tubes. Or original TELEFUNKEN EL156s with their G10A/Stahl 10 sockets and their plate pin located far apart from any other one. Or cheap, reliable, beefy (but ugly) all-glass socket GU50s and solid ceramic bases they're sitting on.

Best regards!

The one I like is Mullard YL1150: beam tetrode, 75W Pa, Mullard claimed 200W in AB1 running at 600V with G2 at 250V, THDF 2% Septar base and top cap - gold plated too. I had a pair and never used them. gm was 35 I'll bet it would have made a super triode.

I believe that an American industrial number (8xxx) was issued, but the 0 at the end of the number (1150) tells us that it was a prototype sadly.

The final generation of valves produced in the 1960s for professional purposes has always interested me.

Paul

[Funker]

Originally Posted by 7N7

Yes good points,

I cut my teeth repairing music amplifiers - for guitars and so on, and had to replace several valve bases, these being octals for EL34s running at around 450V. The problem was of course tracking.

I was always amazed at Mullard's data offering 100W from a pair of EL34s in Class B, running at 800V; I suppose that Mullard had access to exceptionally good sockets - PTFE perhaps?

For high voltage stuff I am much happier to see the anode connection at the top of the valve where it rightly belongs!

Paul

Hi Paul,

For high voltage stuff I am much happier to see the anode connection at the top of the valve where it rightly belongs!

100% agreement!


Real valves have Top caps!!!


73
Wolfgang

[puremilk]

PT15 or F2A is my chioce.