ppp el84 fixed bias schematics

[jogas]

Hello everybody,

I am new in this forum and I would like to ask you for any site where I can find a ppp el84 schematic, (hopefully with a fixed bias) or a schematic of any famous brand like beard or manley with their multi parallel el-84 push pull...

Thanks in advance 🙂

 

[analog_sa]

I am not a big fan of paralleled EL84s and would rather use a larger valve if more power is needed.

 

[DrDeville]

I am not a big fan of paralleled EL84s and would rather use a larger valve if more power is needed.

Interesting. Can you recommend a euphonic pentode with plate dissipation comparable to paralleled KT90s at a B+ of 400V--say about 100W per tube? I need pentodes so I can switch between Ultralinear and Triode mode in my cathode-feedback design.

I just thought I'd ask. 🙂

Best,

George Ferguson

 

[fdegrove]

Hi,

I just thought I'd ask.

Anything else on that wishlist, George?😀

Penthodes like that exist but think B+ in the order of 1KV and higher.

Cheers,😉

 

[DrDeville]

Anything else on that wishlist, George? 😀

Oh yeah, plenty. But none I can share in polite company. 😉

Out of curiosity, what are your favorite / most euphonic big penthodes (100W+ plate dissipation)? Are any in current production?

A guy can dream, can't he?

Thanks,

George "Oooh, Nice Tubes!" Ferguson

 

[fdegrove]

Hi,

Out of curiosity, what are your favorite / most euphonic big penthodes (100W+ plate dissipation)? Are any in current production?

I'm afraid I never went down that road.

A guy can dream, can't he?

Cetainly....not that I would dream about those big bottles but, why not?

Cheers, 😉

 

[DrDeville]

Thanks for the reply Frank--just curious.

not that I would dream about those big bottles

Fair enough--that is a path (100W pentodes) that I don't actually plan to pursue. Consider it the fleeting fantasy of a thermionic adolescent. My inexperienced hormones respond to anything that glows. 😀

Best,

George "I Swear, I Never Inhaled!" Ferguson

 

[Fuling]

big penthodes (100W+ plate dissipation)? Are any in current production?

813
Still being made in China but NOS quality brands are cheap and easy to find.

 

[DrDeville]

Thank you Sir! 🙂

Wow!😱

The data sheet alone is fearsome!
2KV, 100W plate dissipation, 5 amp filament...

Wow!

Thanks again,

George "We Now Return You To Your Thread, Which is Already In Progress" Ferguson

 

[fdegrove]

Hi,

Not that it matters much but the 813 is a beam tetrode.

The nicest sample I've seen so far was a TT10, a Marconi equivalent.

Errr....George, this is just a dream, right?
We'd like to have you around for a long time...at 2.5KV it only takes a split second and it's not even

Careful,😉

 

[DrDeville]

Not that it matters much but the 813 is a beam tetrode.

Pentode, penthode, tetrode--I'd be just as dead either way, right? 😉

Errr....George, this is just a dream, right?

Frank!

You like me! You really like me!

Gee, considering my inexperience and my sense of humor, I thought you'd be encouraging me to test B+ with my tongue.

Don't worry--I won't let it go to my head--I imagine you're simply a kind soul who avoids stepping on spiders, etc. 😉

Seriously, I thought my 😱 and "fearsome" were enough, but no, I am merely fantasizing. I have enough on my plate surviving my current project's 450V B+. And then there's making it actually sound good... 🙂

And the last time I even mentioned 1000V+ in a thought experiment, SY nearly b*tch-slapped me into next Tuesday.

Don't worry--if I'm going to risk my life at insanely high voltages, it will be for a triode.

Something like this:

http://www.nutshellhifi.com/VSAC2003-2.html

(I especially like the 2' long adjusting tool. 😀 )

Thanks for your concern.

Best,

George Ferguson

 

[RE 604]

Hello ,
don´t forget the Siemens RS 1003 and it´s east european equivalent , the SRS 551 , cheap and easy to find on E - Bay Germany , only the sockets are a little bit rare .
Na~ 105 Watt
Ua 800 Volt
Ug2 380 Volt
Ia 200 mA

The next tube , I like much , is the YL 1350 from Telefunken , a modern tube and one of the latest works in the Ulmer factory .
You can see a picture from this tube on my homepage .
I plan , to build a SE amp with this tube .

You need only a maximum voltage from 800 V for this modern tubes , they are easy to drive and because they are longlife professional tubes , they last 10000 hours .

But I think , this is more an european project , because this tubes are not well known in the USA .
Kindly regards , Alex .

 

[Fuling]

Just to mention it: 813 has really nice curves when hooked up as triodes.
I´m giong to run mine in SE at 900V 80mA into 9,2k and I´m expecting almost 27W if I can push the grid to +20V (which shouldn´t be much of a problem since it draws a very moderate grid current)

 

[DrDeville]

Many thanks for the info, guys. I don't have enough experience yet to develop prejudices for or against any type of tube. 🙂

And nice site RE--nice tube photos.

Best,

George "I Like To Watch" Ferguson

 

[jueic]

Folks,

This aussie tube might be a good starting point to make your dream comes true.

http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&category=933&item=5704132833&rd=1

It even comes with a chair, so you can sit down and relax after you hook up all the circuit.

Be quick !! Bid ends in 5 days.

JueiC

 

[DrDeville]

Thanks JueiC,

That put a big smile on my face. 😀

Best,

George "The Mighty OZ Has Spoken!" Ferguson

 

[aurt]

JueiC,

Extremely cool. Have to love an electric octopus.

 

[dady]

Dear friend, do you know how is the impedance of the transformer for use with a RS1003 and what about of its linearity? i like this tube but never hear one, i wanting to do an amp trying with screen exited and g1 to ground like tim de paravicini one but in pushpull for big power and DC coupled.
Best Regards
Esteban Bikic
dady@comodoro.com