[JazzVinyl]

I made an adapter myself  an here you can have a pic with 6L6GC (same pinout as EL34) and 6N7GT.  (the 6L6G is a less powerfull than EL34 and it is already a lot for T1).



The principle used for the adapter is :

Excellent work, hpamdr!

Thank you for the picture and for sharing the info.

 

[Suuup]

 

[hypnos1]

 
OMG, Suuup....RIP Elise!!...

 

[JazzVinyl]

6C33C tube Spec sheet:
http://tdsl.duncanamps.com/dcigna/tubes/sheets/misc/6c33c.txt


I see a lot of 20 watt speaker amps built with this tube. Many as 'Mono Blocks':


http://www.tubeguru.eu/poweramps/6c33c-se-mono/

http://www.dmitrynizh.com/ecc99-6c33c-se.htm

http://www.ebay.com/itm/Acuhorn-S1-The-Touch-of-Speed-Stereo-Amplifier-Tube-6C33C-SE-Triode-OTL-Hi-Tech-/321703739789

 

[WB2016]

I made an adapter myself  an here you can have a pic with 6L6GC (same pinout as EL34) and 6N7GT.  (the 6L6G is a less powerfull than EL34 and it is already a lot for T1).

 
The principle used for the adapter is :

 


Very cool, thanks for the info.

I still am curious about the EL34, maybe it can be used to drive the hard to drive headphones, especially hifiman's, good EL34s have a very good reputation and are not that expensive. Also keep there sweetspot consistent for in excess of 10.000 hrs. You would need to do some external heating for the power draw I imagine.

How are you liking the sound of the 6L6s? I assume like the EL series they require over 200h to properly burn in.

Cheers
WB

 

[Audict123]

   
OMG, Suuup....RIP Elise!!...

Coming from ECC88/6DJ8 preamp tubes, I thought the tubes of the Elise were big. These 6C33C are terrifying. Somehow the mammoth FDD20 adapters blend in well though!

 

[Audict123]

Here's a question for the techies...
 
I'm still facinated about the single triode 6C5G analogues of the twin triode 6N7G. Probably just because I fancy ST shaped tubes, can't have enough of them ... The replacement results in half the gain of course (mu of 20 instead of 40) . Looking at the Mu of the power tubes often used with the Elise below, it could provide a means to level the total gain when using powers with relativey high Mu - like the 5998. If net gain is the result of the multiplication of the Mu's of the driver and power tubes , the combined Mu of the combination of 6C5G and 5998 would be close to that of a 6N7G with 6AS7G.
 
5998 Mu = 5.4, Gm = 15500, Rplate = 350 ohms, Vplate max = 250 volts and Vplate max 5998A = 275V
6AS7G Mu = 2, Gm = 7000, Rplate = 280 ohms)
6080 Mu = 2, Gm = 6500-7000, Rplate = 280-300 ohms
 
Could that be an advantage in certain cases?

 

[2359glenn]

  Here's a question for the techies...
 
I'm still facinated about the single triode 6C5G analogues of the twin triode 6N7G. Probably just because I fancy ST shaped tubes, can't have enough of them ... The replacement results in half the gain of course (mu of 20 instead of 40) . Looking at the Mu of the power tubes often used with the Elise below, it could provide a means to level the total gain when using powers with relativey high Mu - like the 5998. If net gain is the result of the multiplication of the Mu's of the driver and power tubes , the combined Mu of the combination of 6C5G and 5998 would be close to that of a 6N7G with 6AS7G.
 
5998 Mu = 5.4, Gm = 15500, Rplate = 350 ohms, Vplate max = 250 volts and Vplate max 5998A = 275V
6AS7G Mu = 2, Gm = 7000, Rplate = 280 ohms)
6080 Mu = 2, Gm = 6500-7000, Rplate = 280-300 ohms
 
Could that be an advantage in certain cases?

The output circuit is a cathode follower and has a gain of 1 actually less so there is no gain on the output tube.

 

[JazzVinyl]

The output circuit is a cathode follower and has a gain of 1 actually less so there is no gain on the output tube.

I take it in my reading that the Cathode Follower circuit provides "current" to drive loads, and also lowers the output impedance. Never has a gain of more than 1, and is very linear.

The driver tube does the actual amplification of the signal, the amplified signal is taken from the cathode, which has a resistor attached to it (for bias). The value of this resistor depends on how much voltage is applied to the plate. The value of the bias resistor influences the impedance of the signal found at this stage of the amp.

The signal coming off the cathode of the driver tube is too weak and high in impedance to drive a pair of headphones, so the "Cathode Follower" is employed to strengthen the signal and lower the impedance.

Ideally, in an OTL amp, the impedance value of the signal coming off the cathode of the last tube in the circuit (your 'power' tube in Elise) is the 'ideal' impedance for a pair headphones.

This is why OTL amps are generally more suited to higher impedance headphones (150~600 ohms) and less suited to low impedance cans.



Think I have most of that right, please correct me, if not.

 

[Audict123]

Thanks for this free lecture gentlemen! It's really nice to understand a little what the tubes are doing in the Elise.

 

[nojdrof]

Received my Elise today.


WOW!

 

[nojdrof]

WOW!

 

[hpamdr]

Very cool, thanks for the info.

I still am curious about the EL34, maybe it can be used to drive the hard to drive headphones, especially hifiman's, good EL34s have a very good reputation and are not that expensive. Also keep there sweetspot consistent for in excess of 10.000 hrs. You would need to do some external heating for the power draw I imagine.

How are you liking the sound of the 6L6s? I assume like the EL series they require over 200h to properly burn in.

Cheers
WB

if you use only one EL34 by side, you do not need any external heating circuit. An EL34 only use 1.5A on 6.3V which is 1A less than a 6AS7G. Keep also in mind that you will not get full power as you only run in 140V in triode mode, EL34 usually run above 250v and even more on guitar amps and using beam tetrode mode.
Original phillips/siemens or american NOS EL34 sound great.
I like the sound of 6L6 for Blues, Jazz, trip-hop it is Bassy with a great soundstage it is not as clean as GEC6080. I should aslo give a look to double EL84 but need time to build adapters and get tubes.

 

[hpamdr]

WOW!

Welcome on board....
keep in mind that tube need to be burned and Elise have at least 50H in more than 10 listening sessions to really start to shine. In two weeks you will have a beter idea of what she can do for your ears... and your face
 

 

[UntilThen]

WOW!

Sounds good. Glad you like it nojdrof. Been waiting a while to hear from you.