• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

How much spl can a triode take?

If your SPL is high enough to damage tubes, your eardrums would have already departed, mooting the issue.

The main concern is microphonics, that is, a tendency of some tubes to act as vibration sensors and hence cause undesired feedback at certain frequencies. If you keep your amps behind your speakers or several feet remote from them, you're unlikely to have an issue unless you have some really poor tubes in it.
 
If your SPL is high enough to damage tubes, your eardrums would have already departed, mooting the issue.

The main concern is microphonics, that is, a tendency of some tubes to act as vibration sensors and hence cause undesired feedback at certain frequencies. If you keep your amps behind your speakers or several feet remote from them, you're unlikely to have an issue unless you have some really poor tubes in it.

as far as I remember low bass does not hurt your hearing like high freq. Most of my spl has to so with a ton of low.. Yes the highs make my ears ring.. Everything has a resonate frequency, my 2500 sq ft house as testament. It really feels like it would break the filaments, I can't even see straight typing this....
 
I didn't know they had a limit, thanks!! I'll make a 10w set dual mono.. I've been cars at 140db, this setup you cannot compare, way more. My printer almost fell off of my desk, and those svs's walk off, yep 100# and they leave the ground and wander. I appreciate the help, another project 300 tubes...
 
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If your SPL is high enough to damage tubes, your eardrums would have already departed, mooting the issue.

In all my years I have seen exactly one tube damaged by "sound."

We lived near enough to Homestead Air Force base to experience several sonic booms per week from the F104 Starfighters cracking the sound barrier in the 1960's. One of my neighbors who was in the US Coast Guard said his TV died at exactly the same moment of a rather loud sonic boom. Autopsy revealed a broken horizontal output tube.

Any directly heated tube has a rather fragile filament, thoriated filaments become brittle with repeated heating and cooling cycles. It may be possible to break a DHT filament with excessive bass, although I have never seen one. I have been known to play my guitar through a 300B amp, I won't set that amp on top of the speaker cabinet.
 
In all my years I have seen exactly one tube damaged by "sound."

We lived near enough to Homestead Air Force base to experience several sonic booms per week from the F104 Starfighters cracking the sound barrier in the 1960's. One of my neighbors who was in the US Coast Guard said his TV died at exactly the same moment of a rather loud sonic boom. Autopsy revealed a broken horizontal output tube.

Any directly heated tube has a rather fragile filament, thoriated filaments become brittle with repeated heating and cooling cycles. It may be possible to break a DHT filament with excessive bass, although I have never seen one. I have been known to play my guitar through a 300B amp, I won't set that amp on top of the speaker cabinet.

I love the wit and humor, really I do. Those glass thingys look like they need a warning label. I've tried to blow this whole thing up many times over just to prove it's rock solid, I guess it is. The other thing is, according to my kill-a-watt meter these subs are not running up to spec, maybe it's a good thing. The most I ever saw on the imput side was 575w. I am only running them with variable preamp out from my denon cd. I know I don't need more those things are scary......
 
I'll never forget a good friend Mr. Smith, who passed away many years ago. He was an electronic guy who had some neat stuff. A tube repair machine? An old one, it puzzles me to this day how it really worked, I have no clue. I should have helped his wife sell that beautiful mint maranz 9, and he had speakers the size of freezers that he said had 24" woofers. I think they were electrovioce if im not mistaken, Huge. They were all impressions with 20/20 hindsight. I didn't know audio like I do now or I would have bought everything for a grand....