EL84/6V6GT-based famous designs switch to E130L: anyone?

[roberto]

Hi,

by serendipity, while searching other things for other projects, I saw the E130L datasheet: https://frank.pocnet.net/sheets/009/e/E130L.pdf
The incredibly high mutual conductance ( S = 27,5 mA/V) made me think about using it as a substitute for EL84/6V6GT based projects to get four times the output power on one fifth of the Raa load.
Internal resistance in pentode is 10 kOhm, one fourth of the EL84 (38 kOhm) and one fifth of the 6V6GT (50 kOhm).

First projects that comes to mind are:
- Trainwreck Songwriter, Liverpool, Rocket, Express;
- Vox AC30;
- etc...

With a center tapped secondary on PT we can have a solid 150Vdc from a 300Vdc B+, and connect it to the screens of the E130L.
Has anyone ever tried something similar? Tubelab, gingertube?

Thanks
Roberto

[Stevem]

Well first off to me one can't really put EL84s and 6V6s in the same Boat because in the first place audio / response wise the 6V6 is a Beam type tube, and the 84 is not, then follow that up with the 84 having a higher gm going on in it!

So to me the fact that the EL130l is not a beam then Apples to Apple your looking at the 84 pitted against the 130L.

[roberto]

To beam or not to beam.

Thanks for your reply Stevem, may I ask you why you would restrict the possibility to swap one or another based on the contruction of the tube?
It would mean not to compare a 6L6GC beam power tetrode amp to a EL34 power pentode one just because they are not the same kind of apples.
Everybody does it. What matters is tone.

[Phil_S]

Heck, you should try it. I don't see what you have to lose. 60W from a pair according to the data sheet. If it doesn't pan out, you can reconfigure for 6V6 or whatever.

Do you have a source for these tubes? OTOH, there is always eBay. Snap these up before someone else does.
https://www.ebay.com/itm/Telefunken-E-1 ... SwdnNeNcTh
Inside the EU may be better for you. Shipping from US may be a deal killer.
https://www.ebay.com/itm/2-X-E130L-TUBE ... SwLgNfmnK5
Looks like there may be Soviet block made.
https://www.ebay.com/itm/E130L-MICRON-P ... SwDVJetVUn

[roberto]

Heck, you should try it. I don't see what you have to lose. 60W from a pair according to the data sheet. If it doesn't pan out, you can reconfigure for 6V6 or whatever.

Thank you for your reply Phil,
I've an italian supplier for NOS matched ones, even if I pay them more than your first link, but considering shipment, taxes etc.. the italian one becomes cheaper.

It's not that easy as you wrote, as it is needed to change:
- the power supply configuration;
- the power supply transformer;
- the output transformer;
- the chassis for the top cap anode contact;
- ect...

It's not a drop-in modification.
I'm just curious to know if anyone ever tried them for guitar amps.

[Phil_S]

It's not that easy as you wrote, as it is needed to change:
- the power supply configuration;
- the power supply transformer;
- the output transformer;
- the chassis for the top cap anode contact;
- ect...

It's not a drop-in modification.

That's the whole idea, isn't it? Someone needs to try it. You can go first! The data sheet says it's good for audio amplifier. What more do you need?

[roberto]

Thanks Phil, but I don't need motivation, I'm just looking to someone who has already tried them (Tubelab and gingertube seem the most probable ones) to know how they sound for instrument amplification and how to get the best in this scenario.
In HiFi they are used constantly, but requirements are way different.

Thanks.

[Stevem]

Yup! I fully understand that whatever response, feel and tone puts a smile on your face is the way to by far, but I was just responding to you on a technical basis.

[roberto]

Thanks Stevem for your technical intervention.