Salut !
Non c'est l'EL84 qui est la plus puissante (enfin qui rend le plus fort volume) je l'aurais bien expliqué en français mais j'ai la flemme alors je te fais part d'une discution que j'ai eu avec Matin Kidd de chez Cornford, j'espere que ça t'aideras....
A+++
"Martin Kidd here: Cornford's amp designer and co-founder.
The volume difference you are experiencing between the 8-pin and 9-pin settings on your Carrera is quite normal; the EL84 has a higher transconductance, which is measured in milliamps per volt and means that for a given input voltage at the control grid the valve passes a certain amount of current. The transconductance of the EL84 is about 11 milliamps per volt, whereas the transconductance for the 6L6 is between 5 and 6 milliamps per volt, which is approximately half. This means, in theory at least, that an input of 1 volt at the control grid of the EL84 will cause it to pass a current of about 11 m.A, which will cause about 77 Volts to appear across the primary side of the output transformer (this won't be the case in practice because there are other parameters of the valve that change when a signal is applied to the control grid). In the case of the 6L6, approximately half that figure (between 35 and 42 volts) will appear. You can see from this that the bigger valve, while it has the ability to dissipate more power, also needs to be driven harder. As the Carrera uses the same preamp to drive each of the output valves, different results are bound to occur with different output valves and is precisely the idea behind having this feature on the amp; it is not there to obtain more volume but to achieve a different tone. You will also find that the EL84 has a tone, which is focused more around the midrange. Increasing the midrange setting when switching to the 6L6 will address, to some degree at least, the difference in volume."
Un grand homme est celui qui ne perd pas son coeur d'enfant
