Different output tubes

[apb]

I don’t understand your point.

If the speaker is 4 ohms @25 watts you would use 5.7v for 1/3 power.

IMO this is a good way to go because it is a very simple approach.

1/3 power is in no way ambiguous but you do have to calculate it correctly. You can’t calculate the voltage without using the resistance. This is clearly stated in the links you posted and there is even a program the will do the calcs for you if you plug in the numbers.

If you run a 4 ohm 25w speaker at 8v it will dissipate about 16w which is 2x the recommended value so yes it may get hot because it is dissipating 2/3 rated power not the recommended 1/3.

[Robin]

whatever you say

[apb]

That seems a bit snide and not really conducive to reasoned discussion and increased understanding.

[Robin]

Wow, really? Snide? I was agreeing with your reasoned understanding

The help and comments posted here on the TAN site are read by all levels of amp building enthusiasts. Many are just looking to build an amp for what might be a lower cost than they could spend for a boutique-style amp as great as the Two Stroke. We have helped so many first time builders that have no background or even interest in how tube amps work. It’s important to consider this when posting on the site. Saying that 8.1 volts is the correct voltage for a C10R, or any 25w speaker is only part of the equation and taken at face value, could lead a beginner into trouble. I’m glad you had success with your speaker break-in. Continued good luck with your amp building.

[apb]

I like your edited response.

Perhaps we can get some more comments on speakers or tubes.

[Author]

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