Underpowering Orange terror bass

[Metropolis_488]

Apples and Oranges. You guys crack me up. HiFi speaker systems and Bass Cabs are two very different animals...
"Underpowering" is a thing in the HiFi speaker systems world. It is not a thing in Bass Cabs.

Not sure what is cracking you up... sounds like you agree with me:

In the application of your bass amp and a purpose built bass cabinet, I think it is extremely unlikely you would damage a speaker in this fashion. The drivers and tweeters found in your bass cabinet are extremely durable and built to handle distortion / noise.....

In the HiFi, audiophile world, the drivers that comprise the “speaker system” are purpose built with very a different intention than what is found in “Pro-audio” (instrument amplification and PA systems, for example).

 

[Downunderwonder]

In the application of your bass amp and a purpose built bass cabinet, I think it is extremely unlikely you would damage a speaker in this fashion. The drivers and tweeters found in your bass cabinet are extremely durable and built to handle distortion / noise.


However, as someone who builds HiFi Stereo amps and speakers and has damaged a driver with only 3 watts, please let me share my experience:


In the HiFi, audiophile world, the drivers that comprise the “speaker system” are purpose built with very a different intention than what is found in “Pro-audio” (instrument amplification and PA systems, for example). A great example of this are HiFi tweeters of various designs: ribbons, diaphragms, silk domes, metal domes thinner than a human hair – very fragile…. Basically a whole bunch of stuff you could never use to directly amplify your bass or guitar. Some of them can handle a fair bit of power (40 or 50 watts). What they can NOT handle is a distorted signal. They are designed to provide a “flat” frequency response across a given range. Most importantly, they are designed to receive a signal that is very low distortion (this is HiFi audio, after all). Distorted signals will actually damage the mechanical materials in many of these tweeters (especially ribbons), regardless of the amount of wattage thrown at them.


For an anecdote, just look at entry level integrated stereo amplifiers – their distortion specs AT MAX OUTPUT are usually around 0.01% Total harmonic distortion. THD is much lower within the normal operating range (like 0.001% THD or less – remember, generally speaking, THD increases as an amplification device is pushed to edge of its operating limits). A clipping amplifier producing 1% THD is sending a signal that is 100 times more distorted than the max THD produced by one of these stereo amplifiers.


So how do you damage a speaker by underpowering it? If you have a low powered amp and try to make it go louder than it is designed to go, you can create a relatively high amount of THD, while still only producing a few watts. Take something like a 2A3 tube based single ended triode amp. It produces up to 3 to 3.5 watts before getting close to 1% THD (within their operating range they sound amazing, BTW). If you try and push the amp and “cheat” by increasing the gain of a pre-amp you can cause the amp to clip as much as 4% or 5%. I did this and boom – metal dome tweeter damaged (it still functioned, but crackled when played). The driver was capable of handling much more wattage. It was NOT capable of handling being fed a signal with 5% THD. You do not need to hit the driver with a square wave to damage it. These tweeters will fail long before a square wave is applied.


So, YES, in some applications, damaging a speaker by underpowering is a real thing.

Keyword : tweeter.

 

[Volker Kirstein]

Not sure what is cracking you up... sounds like you agree with me:

Not you, individually, per se. The whole "yes it is! no it isn't!" thing was entertaining (for me) to read.

 

[SteveIII]

So I shouldn't play a recording of distorted guitar through my home stereo? How does the speaker know if the distortion is from the amplifier or the source material?
What about synthesizer music. My mono synth lets me stack three square waves or use one at a time. Are you saying if I play music recorded with a minimoog set to square wave it will magically blow my speakers? Cause there aren't that many recordings with minimoogs right?
Area under the curve is power ouput. Home audio just has more drivers with not enough xmax and passive crossovers that shift frequency response when the system pushed too hard causing voice coil impedance to change. Just because the woofer on a system is rated for 50 watts doesn't mean the tweeter is. And there is more high frequency content in distortion. Add in dropping crossover frequency and voila you blew your "50 watt" speaker with 4 or 5 watts.
Honestly go back to the synth thing. There are freaking square wave settings. People intentionally make square waves to play through speakers and they are in so many pieces of music we would have heard of the epidemic of all the speakers in the world failing because they played square waves

 

[Nebadon2000]

Warned you Metro

 

[SteveIII]

If you are going to reply at least attempt to answer my questions. If people are blowing speakers because they can't hear the distortion causing damage that is hardly audiophile level listening.
And who can be bothered using low powered amps with 89db efficiency speakers. If you read the barefaced link and really got it the thread would be done.
Try modeling some speaker cabinets. A lot of designs run out of xmax at ridiculously low power levels with low frequency. That could be where some of your stuck voice coils are. I have a cab with a speaker rated for 400 watts rms, but it is limited to 200 watts rms below 100 hz because of xmax. If I changed the size of the cab it could be even more limited.
I'm not trying to troll, try answering some of the questions I asked.

 

[Jaco who?]

So how do you damage a speaker by underpowering it? If you have a low powered amp and try to make it go louder than it is designed to go, you can create a relatively high amount of THD, while still only producing a few watts. Take something like a 2A3 tube based single ended triode amp. It produces up to 3 to 3.5 watts before getting close to 1% THD (within their operating range they sound amazing, BTW). If you try and push the amp and “cheat” by increasing the gain of a pre-amp you can cause the amp to clip as much as 4% or 5%. I did this and boom – metal dome tweeter damaged (it still functioned, but crackled when played). The driver was capable of handling much more wattage. It was NOT capable of handling being fed a signal with 5% THD. You do not need to hit the driver with a square wave to damage it. These tweeters will fail long before a square wave is applied.


So, YES, in some applications, damaging a speaker by underpowering is a real thing.

BUT - your metal dome tweeter is not a speaker. It's a TWEETER.

So I shouldn't play a recording of distorted guitar through my home stereo? How does the speaker know if the distortion is from the amplifier or the source material?
What about synthesizer music. My mono synth lets me stack three square waves or use one at a time. Are you saying if I play music recorded with a minimoog set to square wave it will magically blow my speakers? Cause there aren't that many recordings with minimoogs right?
Area under the curve is power ouput. Home audio just has more drivers with not enough xmax and passive crossovers that shift frequency response when the system pushed too hard causing voice coil impedance to change. Just because the woofer on a system is rated for 50 watts doesn't mean the tweeter is. And there is more high frequency content in distortion. Add in dropping crossover frequency and voila you blew your "50 watt" speaker with 4 or 5 watts.
Honestly go back to the synth thing. There are freaking square wave settings. People intentionally make square waves to play through speakers and they are in so many pieces of music we would have heard of the epidemic of all the speakers in the world failing because they played square waves

Recorded music is recorded with carefull attention paid to DBu meters. If you intentionally fudged the input signal on the preamp section of your home hifi, it could in a way re-create a recording that had the DBu meters pegged and you might blow the tweeter in your home stereo. And No, I don't know what any of this has to do with Bass Guitar speakers.

 

[moody]

1.) semantics on the word underpowering where the appropriate word is overpowering. The 'rating' if an amp can't be taken at face value and if driven can put out significantly more power.
2.) square waves vs. distortion. Neither matter if they are within the limits of the speakers power handling.

I have destroyed speakers both by overpowering with a high wattage amp and overpowering with a much lower wattage amp. The sound made by the speaker before dying is not the same - but they die just the same.