SE amplifier advice..

[Dxvideo]

Hi all,

I am not a newbie DIYer (may be as you already know...). And have made a lot of IC, SS amplifiers, tube buffers-preamps for my ear taste until now. Presently I have a pair of Tang Band W5-1611SA full range speaker with 17lt bass reflex box tuned @52Hz.. And a Pass F5 amplifier feeds them. I must say that I found them very satisfactory at the meaning of analytical/clinical sounding. However I think my soul needs more musical things to listen.. Like a SE tube amplifier..
So, at this time I will need your advices about the choice..
I have a pair of NOS EL34, some 6N6P and some 12AU7s in my drawer.. In fact what I have is not important. But I see a lot of SE applications with EL34 tubes in the internet.
I think just a triode input stage (with SRPP may be) and an EL34 works fine for my needs. However I cannot be sure to select one of these projects..
May you please advice a SE project for me?
And what about the output transformers? Does a HAMMOND 1628SEA suitable for this amp or a cheaper one like;
5K SE AUDIO OUTPUT TRANSFORMER FOR ,KT-88, EL-34 | eBay

Thanks a lot in advance for anykind of helps..

[azazello]

....Hammond 125 FSE.
You can buy from Tube-Town Online-Store - Germany
12AU7 is suitable for EL34.

[quikie22]

This sounds pretty good. RH 807 - Tube Audio ...... RH DESIGN

You could use the EL34 instead of the 807. Driver stage with 12AT7 can be augmented by a cathode follower constructed from 6N6P.

[Dxvideo]

Thanks a lot.. But is it just 1.5W ???
I afraid it wont be enough for me!

[quikie22]

Please read through fully. 1.5W was referencing the single-ended triode connected EL84 amp he had listened to. :-)

This one should provide much more than that. Even the RH84 which is based on a similar design but with EL84 puts out about 4W of power.

EL34 should easily double that. If you use a cathode follower, you can probably drive it into A2 territory too... with even higher power.

[Dxvideo]

hmmm.. I gues I must make some mods on the circuit! However I dont think so.. May you explain a bit more please?

[quikie22]

here is one schematic. I have made a circuit similar to this using gu-50 and 6N6P and 12AT7. Look at artosalo's design. This is what I meant. You could replace the GU-50 with any output tube of choice but of course with different transformers and bias schemes.

GU-50 in Single-Ended Triode Configuration - What bias points?

[Dxvideo]

Sure.. But this is my first tube power amp. So I dont think I can do that. Thanks a lot.

[quikie22]

:-) The RH84 was my first tube power amp project. The GU-50 my second one. :-)

Like you, i had already completed several SS amps (chipamps, Pass F5, Pass BOZ, various MOSFET/BJT amps) before my foray into tubes. You will be surprised how similar tube circuits are and are in fact simpler to grasp.

There a lots of circuits floating out there in cyberspace. Have a look at all of them and decide. Took me 3 months of research and another 3 to get the parts for my first EL84 amp.

You will be surprised how loud 4W or 8W can get you with tube equipment. I guess the 2nd harmonic distortion tends to "fatten" the sound and make it louder than the SS amps. The 8W GU-50 amp seems to beat the F5 easily. I think many of those on this forum have the same experience.

[carbondated]

Thanks for this suggestion. For the power supply my ground comes from the centre tap and the HT is referenced to that... so how does one get a negative voltage?