things effect the tube power

[kldguitar]

according to the paramter of 6L6, the maximum signal power is 10.5w in plate voltage 350v Class a .EL34 , the maximun signal power is 11w in Class A.
plate voltage 265 v class A. In fact, there are still other things effect the power of tube.
1. The plate voltage
2the bias voltage
3. The prime impedance of out put transform.
Do you knowwhat else effect the power of tube? Thanks.
http://www.kldguitar.com

[Chuck H]

I'll assume by the way your post is written that your intending to use a tube (or tubes) in class A.

Yes, all the things you mention affect a tubes output power. The max output at a given voltage remains the same. Max is max. ie: If you intend to try to get more power out of the tube by running a lower primary impedance on the OT then you will need to reduce the current in order to keep the tube within it's operating parameters. However, the tone will be different between a tube running into a highish primary impedance at a higher current than the same tube into a lower primary imedance at lower current. But max dissapation still applies. The lower primary impedance will be more punchy and dynamic and the higher primary impedance will be smoother with less tendancy to fart and cackle. Balancing the primary impedance to give the right ratio of punchy and smooth is the real trick.

The bias voltage does not effect the dissapation limit of the tube. But it can effect the output power. If you are biased "correctly" the tube will put out all it can in a predictable manner. If you are biased a hair too cold you may get a little more output, but at the expense of unwanted, and bad sounding distortion types. If you bias the tube really cold you will get reduced power AND bad distortion products. If you bias a hair hot the tube will seem very touch sensitive at lower distortion settings but less clear and defined when pushed and probably with less output power. If you bias very hot the tube will just crumble when strong signals are introduced, like big bass notes and power chords. Dynamics will fade into an overly compressed kind of sound. And again, there will be a lower output power.

Where you bias is dependant upon the plate voltage. If you go higher than the recommended voltages for a given tube you may find that you cannot even bias it correctly to get good tone. If you go too low you will limit the tubes potential for output and dynamics can suffer. Even if you bring up the current you still may not be able to get the tubes full potential output power.

So the goal is to try to build a good environment for the tube/s to operate in. From a guitar amp builder prospective, thats alot of leeway.

I'm dealing with that very issue right now. I am running a pair of el84s at a highish plate voltage. But not too high. El84's seem to shine tone wise either at the lower end of their voltage rating or the higher end. By going down the middle, in an attempt to get some attributes of either operating condition, I'm finding that I'm getting the worst of both situations instead of the best.

It's a good idea to decide what kind of tone your after and follow an existing design that has that kind of tone. That way the guesswork has already been done. Parameters are parameters. All points from the top to the bottom of those parameters present pros and cons. But you won't get more or better performance out of a tube trying to trick it.

Chuck

[Bruce / Mission Amps]

I'll assume by the way your post is written that your intending to use a tube (or tubes) in class A.


Chuck

Chuck I'm sorry you wasted so much time with this shill.
I doubt he is interested in very much more then promoting his (their) Chinese based business.

[kldguitar]

About the primary impedance of ot

Thanks chuck
About bias voltage, it is smaller effect with final power of tube, it is limited by plate voltage, If it is higher, the tube will be damaged, if it is lower, tube work in bad tone.
The plate voltage of tube commonly is parameter not change, if you use Class a, EL84 is 265v.etc.
The important things effect the power and tone of tube is OT.
the primary impedance of OT is depended on the lower Frez. of guitar .
I hope found more article about OT.

[Chuck H]

Thanks Bruce... I should pay more attention. Didn't even see this guy coming. Hope you had a great holiday.