Newbie question: Amplifiers, Volume, Clipping?

Clipping is far less of an issue with tube amps; I would not worry about using triode. If 3 watts give 90db then 6 gives 93db and 12 96. So the triode should give you about 97 db at one meter, actually quite loud in most rooms. Pentode should give over 100. Usually maximum gain is around 1 PM on the volume control but if your source is lower in output than usual it may be higher and vice versa.

Clipping is far less of an issue with tube amps

This is good news. The only thing that I worry about is that I won't hear the clipping (which could silently damage a pair of classic old speakers). What should I be listening for?

Usually maximum gain is around 1 PM on the volume control but if your source is lower in output than usual it may be higher and vice versa.

On Pentode I've been wanting to push it further than 1pm. Should I just not? I've had it at about 3 o'clock without any problems that I could hear...but I guess it depends on the recording...? I don't know how to gauge whether I'm at a threshold or not, though.

If it starts clipping, will I know it? If this happens will my speakers be ruined?

I am the furthest thing from a tube amp expert but with solid state the problem with clipping is that it eventually will let DC through to your speakers; this use to be called hard clipping. I think that tube amps generally exhibit what was called soft clipping, in which they fail to follow the waveform completely but do not let DC through. I am sure Al will roll his eyes if he reads this; I could have explained it much better 40 years ago when I actually used tube amps. Clipping will usually be accompanied by some type of audible distortion but not in every case. I really don't think you will hurt them, why don't you get a Radio Shack sound level meter and see how loud you are playing them? They are not expensive; if you have a hi tech phone it may have an app that does the same thing. I wouldn't know, I am a product of the crank phone era.

No eye-rolling here, Stan, just a good chuckle at your comment :-)

The reason that speakers are commonly damaged by clipping of underpowered amplifiers is essentially as follows: Clipping occurs when the amp is asked to deliver a larger voltage swing at any instant of time than it is capable of delivering. That will usually occur at bass or mid-bass frequencies, where music typically contains its highest energy levels. Clipping means that the positive and negative peaks of what would normally be a smooth sinusoidal waveform will abruptly transition to a flat, essentially constant output level corresponding to the maximum positive and negative voltages that the amp is capable of delivering.

The ABRUPTNESS of those transition points corresponds to high frequency spectral components being present in the output signal that are not present in the original waveform. In other words, the clipped waveform contains excess high frequency energy, which the speaker's crossover will duly route to the tweeter. That can occur even if there is no high frequency energy at all in the original signal, as a result of the clipping of bass frequencies. Tweeters are ordinarily able to handle much less energy than lower frequency drivers, and can therefore be damaged by that excess energy.

Solid state amplifiers will typically clip more abruptly than tube amplifiers, therefore making them more likely to cause that kind of damage. Although if a tube amp is clipped severely enough, the same damage can result.

Severe clipping will be immediately obvious, because the sound will be horribly distorted. The onset of clipping may be characterized by mild distortion or slight popping sounds on musical peaks. I doubt that occasional mild clipping would cause any damage.

The volume control position at which the onset of clipping may occur is, IMO, unpredictable as a practical matter, and will vary very widely depending on the gains and sensitivities of all of the components that are involved, on the output level of the source component, on the power capability of the amplifier, and on the recording.

Best regards,
-- Al