• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

ELL80

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Ell80

Hi

I have in a box, two outputtransformers for use with ELL80, and a powersuply for a little stereo mainamp.
The powertransformer is capabel of +300VDC.
For the moment I use it in a headphoneamp at 250VDC.

What tubes are there on the market today for substitute?
Think perhaps the EL84 is a bit to heavy for these outputtransformers.

I want a tube with a singel pentode inbord.
Or perhaps there is a little triode somewhere to use.:scratch2:

regards
 
Yes, 6DL5 is their foreign name.
Keep me informed about your plans.
I´m want to build the VKS203 circuit with these tiny irons:
 

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Hi KaDe

You are absolutely right they were EL84s. You have a good eye.
:)
It was my intension to build somthing not so complicated with those outputtrannies, but yes I am a openminded man.

The Sennheiser VKS 203 is a real beaty of schematic topology.
The only thing that make me thoughtful, is the choice of ECC83 as drivers. But you can tell me the benefit?

Here is the schematic I was thinking of as the projekt, a very simple but nice sounding little amp.
http://web.telia.com/~u49831149/EL84 or EL95 (Small).jpg
 
EL95 single-ended

I have some EL95 tubes. Fairly enough of them, I'd say.

What do you think about this:
1) Triode strapping EL95 tubes
2) Parallel connecting them
3) Making a single-ended amplifier of them
4) Making two such amplifiers (stereo)

As a pentode the power output of one EL95 is 3W.
Triodised it should be about 1W per tube.

I have been thinking about using four or five EL95 tubes per channel, since I have suitable loudspeaker loads for two 4W or 5W amplifiers.
 
Thanks Yvesm
Baby Huey is also a very interesting princip, for use of old outputtransformers. I will follow it up.

Nikolas
If you go for PPP with 4 tubes, you have to reduce outputtransformer recistance by half, something to think about.
In UL PP near triod, must be the most efficient, I belive, so far.;)

KaDe thanks
I really appreciate these type of information, including componentvalues etc.


EL95 http://tdsl.duncanamps.com/show.php?des=EL95
EL84 http://tdsl.duncanamps.com/show.php?des=EL84

Perhaps there are a possibility of using EL84, with a lot of care?:firefite:
 
EL95 tubes

Originally posted by Ragnwald

Nikolas
If you go for PPP with 4 tubes, you have to reduce outputtransformer recistance by half, something to think about.
In UL PP near triod, must be the most efficient, I belive, so far.;)

I really consider making it single-ended in triode mode. Cost of tubes is not an issue in this case. I think that while power transformers are simple, winding audio transformers is art, and UL transformers are even higher level art. Thus, I'd like to keep the amplifier simple.

Availability is one thing. The other attractive side of using many small power tubes parallel is the possibility to use relatively flat enclosure. For example: Compare one F2a (height = 116mm) and five EL95 (height = 60mm). Yes, I really want the tubes securely inside a steel case, not on top of it.
 
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