Newbie question: Amplifiers, Volume, Clipping?

Hi Bruce,

My statement about the output waveform abruptly transitioning to an essentially constant level was not worded as completely as it should have been. The "constant level" will persist only until a tiny fraction of a second later, when the input voltage to the amplifier is alternating in the opposite direction and is no longer demanding that the amplifier put out a voltage that is larger than it is capable of. At that point there will be an abrupt transition FROM that constant level back to the normal sine wave or sum of sine waves that constitute the musical note.

That pair of transitions will occur near both the positive-going and negative-going peaks of the waveform. Hence the tops and bottoms of the waveform will be "clipped off," which is why it is called clipping. In between those extremes, the waveform will be as it should. DC is not involved in any of this.

The output transformer will pass whatever spectral components (frequency components) of that clipped waveform are within its bandwidth, its bandwidth in most cases being much wider than the nominally audible range of 20Hz to 20kHz, and encompassing most or all of the extraneous (and potentially damage-causing) treble energy that I referred to.

Best regards,
-- Al

Almarg, while admittedly I flunked high school physics and can't always grasp your technical discourse, I always enjoy you're posts--they're unfailingly polite, patient, positive and informative. Thank you for being you.

If 96db avg levels are not sufficient ... either get another amp... or more eff speakers!

Why wonder about where you can break them with the volume knob?

Usually, soft clipping in tube amps sounds like fuzzy audio... distortion in other words, but the clarity of the audio begins to vanish and becomes less distinct. Vague. Soft & fuzzy!

The only other item I can figure out here is that the speakers may be fairly eff, but their imp curves are not quite so friendly.

AS OP said already, these items are not a super great match. Well, then... figure out which is the better item, amp or speakers and keep that. Sell the others.

Or .... get OK with listening at lesser SPLs.

Personally, I"ve never twisted the vol dial above 2 o'clock since I turned 17... and blew my first speaker. Ordinarily, if I have to get above the noon mark on my preamp for pretty good levels, I might have a poor match on my hands and I'm figuring something ain't right already.

the days of twisting that knob all the way over are gone for me. I simply will not do it!

Very good luck developing your outfit.

Loomis, thanks very much! I always find your posts to be informative and enjoyable, as well.

Best regards,
-- Al

Blindjim, I'm with you. Tonight I was listening to an old record that I've owned for 35+ years, George Solti conducting Chicago Symph. Orchestra, Beethoven 9th (London ffrr LP), 4th movement. As is often the case with classical music, Beethoven's 9th, especially the 4th movement, is very dynamic with large swings in SPL. When the full chorus and orchestra were going full tilt, the SPL caused my ears to literally distort. All I could hear was a buzzing sound even though I knew the music was clear as a bell.

So my point is that while you are concerned about turning the gain up too high out of concern for blowing your speakers, I am concerned about blowing my ear drums. Although . . . to actually have been there to hear the 9th live with the chorus and orchestra going full tilt must have been one he*l of an experience. I'll just know to bring ear plugs if I can catch the 9th live now.