Okay.......*** Sweetwater said......

[billfitzmaurice]

I am running a Mesa 8 ohm 600W 4x10 with a Mesa 8 ohm 600W 2x10 and, contrary to the "mismatching guidelines", I seem to be getting great results.

When I had heard about mismatching cabs being bad before, I called up Mesa and asked them... they told me that I was fine because all of their cabs are made to match together.

If I remember the details correctly, they said that the 4x10 contains four speakers rated at 150W a piece, while the 2x10 contains two speakers rated at 300W a piece, so, as far as worrying about mismatching, they are essentially identical as far as the amp is concerned because they are both rated at 8 ohms.

Did they fill me with BS to make me feel better about my purchase, or does this seem like it makes sense to you?

Probably BS. The power ratings of the drivers are moot, displacement is what matters. If the displacement of the 210 is equal to that of the 410 all would be fine. But I doubt that's the case. Ask Mesa what the xmax is for the drivers in the 210 and those in the 410. I doubt you'll get an answer.

 

[BassmanPaul]

There is no such thing as underpowering a cab.

Agreed BUT there is the situation where too little power will be unable to give the cabinet enough power to work to its fullest ability.

 

[JHAz]

I disagree 100%.

Putting 1 watt into a 1000 watt cab will yield very little volume. The point is, when you push an amplifier to it's limits, you create distortion in the signal, that is amplified and sent to the cab. The cab will reproduce this distortion as a square wave and will overheat the speakers as they cool down by moving.

. . .
I power a 200 watt RMS cab with a 4000 watt peak head and I have absolutely no trouble with volume, or being heard. However, I would probably have an issue if those figures were reversed.

Seems to me this conflates power handling with sensitivity. How loud the cab gets at one watt is how sensitivity is defined. The 410 GK MBE is specified at 103 dB with one watt, which is more than a little loud. If your cab gets less and less efficient as you add drivers, you would lose all the benefit of the additional drivers, since every 3 dB of lost sensitivity effectively requires you to double the power to get the same loudness.

 

[derridiandrift]

BillFitzmaurice.info - View topic - Can I underpower my speakers?Will clipping hurt them?

Consider me schooled.

 

[JB696]

I hope we're not moving on already. What would happen if I underpowered my speaker cabinet AND I had a ground loop in the wiring of my passive bass????

 

[seamonkey]

Buy what he recommends, burn it out, send it back for a replacement,
burn it out the replacement, send it back for a refund.

Sweetwater is at least very good at customer support and returns.

 

[cheezewiz]

That surprises me. Sweetwater usually have the best trained phone salesman out there. They are certainly usually more aware than the MF or GC phone serfs.

 

[Jazzdogg]

Again, NO SUCH THING AS UNDERPOWERING <SNIP>

There IS an issue with underpowering a tweeter. If you really push an amp to clip, and the tweeter does not have protection circuitry, you could blow the tweeter diaphragm.

That's an example of overpowering, not underpowering.

 

[Downunderwonder]

Most of us are familiar with the sound of a speaker cabinet that is being overpowered. When the speakers first reach the threshold of farting the notes distort just on the attack of the note and on the lower notes first. But as the power level rises the distortion continues longer into the note and at severe levels will make the note sound like a long fart. With underpowering the speakers, the warning signs are much more subtle and take a more experienced ear to detect. Suppose you are running an 8x10 cab that is rated at 1000 watts. And you are going to drive it with a bass head that you made by sawing the top off of a Behringer 200 watt combo amp. Underpowering of the speakers could happen even with the knob on your bass up all the way, all twelve of the effects on your pedal board maxed, and the Behringer (including all the EQ's) set to ten. The 1000 watt cabinet will try to suck more wattage out of your amp than it can supply. Unlike overpowering, the first audible sign of danger will not be a loud fart on the attack of the note. It will sound like a short squeaker fart, almost a chirp. This tells you that the speaker cabinet has tried to suck so much power out of the amp that now the tranformer has begun to shoot out up to 200 watts of direct current. That is what blows up gear. So if you want to run a rig like you are contemplating just learn to listen for the warning sign, that little chirping sound. And be careful.

OMG, Agatha Christie could write a better crime novel.

 

[madmatt]

I wanna know what he was trying to sell you otherwise...

 

[Hawaii Islander]

When people say 'underpowering' is bad and everyone rolls their eyes and laughs at them, isn't it possible that what they really mean is turning the volume up on a solid-state amp to the point where the amp is clipping and then sending that signal out to the cab is what's bad?

It's impossible for me to believe that they think taking a 100 watt head and turning it up to '2' is going to damage a cab that will handle 1200 watts.

Bingo!

Also, under powering microprocessors (brownouts that lead to voltage dips) are bad. We've lost electronics gear here in Hawaii due to brownouts. I had to replace damage boards in repeater equipment because of brownouts. My boss finally ponied up for adequate surge and brownout protection for the repeater systems.

As far as damaging speaker from actual low power, I don't see that happening. But Thunder Pulse brings up a valid point about pushing an amp too hard to get acceptable volume that could damage the amp by overheating components in the amp.

 

[KJung]

That's an example of overpowering, not underpowering.

You are correct that you can blow a tweeter in a number of ways, especially if the tweeter circuit has no protection. However, running a severly clipped signal into a tweeter can do similar damage. This is not the case with a woofer.

 

[billfitzmaurice]

When people say 'underpowering'... isn't it possible that what they really mean is turning the volume up on a solid-state amp to the point where the amp is clipping and then sending that signal out to the cab is what's bad?

Of course that's what they mean. It's still wrong. And clipping happens with tubes just as much as it does with SS. Whatever the source of the clipping, be it an over-driven power amp or a fuzzbox, clipped waveforms have no effect whatsoever on woofers.

 

[Jonyak]

Of course that's what they mean. It's still wrong. And clipping happens with tubes just as much as it does with SS. Whatever the source of the clipping, be it an over-driven power amp or a fuzzbox, clipped waveforms have no effect whatsoever on woofers.

if they did, I would be in trouble, my big muff is nasty.

 

[JB696]

I like it when people jump in and post without reading through the whole thread first. Sometimes I "forget" to put in all the smiley faces and winks. It's usually good for a few laughs.

 

[billfitzmaurice]

I like it when people jump in and post without reading through the whole thread first. Sometimes I "forget" to put in all the smiley faces and winks. It's usually good for a few laughs.

It's only good for a laugh if we know it's a joke. Unfortunately more than a few readers would think you were serious, and even more would even believe it true, otherwise we wouldn't have to answer this same question ad nauseum ad infinitum.

 

[Horny Toad]

It's only good for a laugh if we know it's a joke. Unfortunately more than a few readers would think you were serious, and even more would even believe it true, otherwise we wouldn't have to answer this same question ad nauseum ad infinitum.

+1

 

[JB696]

There's just something about these "underpowering" threads that I can't resist. Sorry.

 

[nashvillebill]

...clipped waveforms have no effect whatsoever on woofers.

I sure wish we could drive a stake through the "square waves kills speakers" myth, it gets repeated on every forum I've hung out on.

I've deliberately hooked up a square wave sig gen, amplified it, and run it into speakers. Sounded awful... but the speakers survive unscathed. They don't care what the waveform is.

 

[seamonkey]

20 years later this paper is still one of the best on
"POWER AMPLIFIER CLIPPING AND ITS EFFECTS ON
LOUDSPEAKER RELIABILITY"
[Invalid or Expired Link Removed]
Figure 4