Don't expect the impossible from a 15 inch driver!!

[Hounddog409]

I do the same when I use both of my Mesa Subway 115's. I make club Owners now sign a release saying I am not responsible for roof repairs after I tear that sucker off.

Yeah, I need to try out the subway 15's.

Wonder if anyone could compare the UL2 to the Mesa?

 

[rockinbilly]

Hate to be a spoiler alert spoiler, but no you can't.

You can over-power inadvertently with an amp that's smaller than what's needed, and that smaller amp can indeed deliver more than rated power when overdriven.

Square wave, no speaker likes that!. better fuse it !!!!

 

[Hand slap]

That never happens with woofers. A square wave is a sine wave plus all of the harmonics of that sine wave all at the same level. That's explained within this post:
Invalid Link Removed

No musical waveform ever has enough harmonic content to be a square wave. It might be close with a fuzzed out guitar or synth, never with bass. Also, woofer voice coils are inductors. When a signal passes through an inductor the highs are filtered. If the inductor has a high enough value all of the harmonics will be filtered, and when that happens what you end up with is: a sine wave. A woofer voice coil doesn't have that much inductance, but it has enough so that the power the coil has to dissipate is no more with a clipped signal than a clean one. Tweeters can be damaged by clipped wave forms, because they are subjected to much more power than normal. That's why guitar amps don't have tweeters. If clipping killed woofers they wouldn't be able to use those either, but they don't.

Clipping a signal in effect is a square wave, be more then happy to show you on my scope, I have a little experience in audio, was a service cntr for many manufacturers, Marshall/PV/Fender, etc. Regardless, a amp drove into clipping fry voice coils, seen it first hand hundreds of times.

 

[GreyBeard]

A lot has to do with how the speaker is matched to the cabinet. If the cabinet hasn't been tuned to dampen the resonance frequency of the speaker, it can easily over extrude and suffer mechanical failure.

 

[Al Kraft]

I never expect the impossible from any cab, it's a sure way to blow a speaker. However, the Mesa Subway delivers a lot more than I thought possible from a 115 and I've played and owned quite a few 115's over the years.

 

[RoadRanger]

Yah, all my cabs are blown from me driving them with square waves from overdriven amps - NOT . My poor little CTM-30 spends most of its time slamming the needle into its stop - no smoke at tonight's 4 hour torture session LOL.

 

[arbiterusa]

Does everyone actually expect a 300w RMS rated 15 inch driver to actually take 300w ?

Yes, I do. But I buy good gear that does what it says it does.

Someone upthread mentioned Kappalite. I have them. They're amazing.

 

[agedhorse]

Square wave, no speaker likes that!. better fuse it !!!!

Not true at all. Speakers reproduce square waves (and proportions of square waves) all the time. It's just important that you apply the proper derating factors when calculating rated power.

After all, heavily overdriven guitar, synth patches and contain essentially square waves (which are nothing more than a series of dive waves of the fundamental plus harmonics.

. Regardless, a amp drove into clipping fry voice coils, seen it first hand hundreds of times.

not if the proper derating factors are applied by the manufacturer. Heck, even DC is ok up to a certain threshold.

Overall on this thread, there are some significant misunderstandings about speaker power ratings and especially how waveforms apply to the limits of audio in the speaker field.

 

[monsterthompson]

Not true at all. Speakers reproduce square waves (and proportions of square waves) all the time.

Right? If they didn't, every EDM fan would have a blown set of woofers. Square waves are all over that stuff.

 

[Mark Andrew]

Yes, I do. But I buy good gear that does what it says it does.

Someone upthread mentioned Kappalite. I have them. They're amazing.

All this kappalite talk is making me itch to try one. I have recently upgraded my 210 with basslites and it has made the cab much more usable I can use it alone for the first time. So if and when I upgrade my other 15 (not the one blown up in the forrest) what's the exact model I need for full range use? For use in a 115 peavey pro series cab?

 

[Hand slap]

Not true at all. Speakers reproduce square waves (and proportions of square waves) all the time. It's just important that you apply the proper derating factors when calculating rated power.

After all, heavily overdriven guitar, synth patches and contain essentially square waves (which are nothing more than a series of dive waves of the fundamental plus harmonics.

not if the proper derating factors are applied by the manufacturer. Heck, even DC is ok up to a certain threshold.

Overall on this thread, there are some significant misunderstandings about speaker power ratings and especially how waveforms apply to the limits of audio in the speaker field.

Ok, thank you for your expert opinion, and all of the terms, I am just a well seasoned bench tech, not an an engineer.

 

[Old Garage-Bander]

Ok, thank you for your expert opinion, and all of the terms, I am just a well seasoned bench tech, not an an engineer.

If speakers couldn't handle a little DC, then we wouldn't be doing the battery phase test.

Bench tech = The guy caught in between the engineer trying to design something that won't fail, and the user who has designs on making it fail anyway.

 

[Rick James]

Ok, thank you for your expert opinion, and all of the terms, I am just a well seasoned bench tech, not an an engineer.

There's no reason why you can't be both. The best techs are the ones who understand why things work the way they do.

Clipping a signal in effect is a square wave, be more then happy to show you on my scope

The next time you look at a square wave on your scope first run the output of the signal generator through inductors of various values and then into the scope and see how they affect the waveform. Try some capacitors paralleled across the load too, because voice coils have capacitance as well as inductance.

 

[mesaplayer83]

My Mesa Subway 115 will take 300 watts and ask for more. Like Dose said, it's all about the driver and cab design.

What kind of cab is it?

Yup - I have both a Subway 115 and a Powerhouse 115, and they will both easily take that and more... The PH115 has been pushed pretty good by a 600 watt amp *a few* times, and never had a problem... As always, you get what you pay for - that, and MESA ROCKS!!!

 

[Old Garage-Bander]

There's no reason why you can't be both. The best techs are the ones who understand why things work the way they do.
The next time you look at a square wave on your scope first run the output of the signal generator through inductors of various values and then into the scope and see how they affect the waveform. Try some capacitors paralleled across the load too, because voice coils have capacitance as well as inductance.

For all practical purposes, at least for this discussion, a severely clipped sine wave and a square wave have the same affect. Under the scrutiny of analysis that is beyond the scope of this discussion, you will find that the two are derived by very different methods.

A clipped sine wave is a form of distortion. The sine wave is distorted into something that is no longer a sine wave.
A square wave, as has been pointed out previously, is still a sine wave but one that contains all of, or at least a significant portion of, that sine wave's harmonic energy. Clipping is not necessarily involved in a square wave.

When you clip a sine wave, all you do is not allow the peaks to develop. It still has the same rise and fall times as the unclipped sine wave, so technically it is not "square." It can look square however, if there is significant clipping involved.

 

[lpbfender]

I never expect the impossible from any cab, it's a sure way to blow a speaker. However, the Mesa Subway delivers a lot more than I thought possible from a 115 and I've played and owned quite a few 115's over the years.

How does it compare to the Eden 2-15 XLT? ( besides weight)

 

[lpbfender]

How does it compare to the Eden 2-15 XLT? ( besides weight)

Sorry
1-15xlt

 

[Treebeard]

I have two Kustom Deep End 250w 15" neo cabs. I tried one with my Hartke 3500 (240w at 8ohms) at practice and that cab wanted to die. I tried both cabs with the same head (175w per cab @ 4o) and the sound was perfection. Interesting.

 

[Hand slap]

If speakers couldn't handle a little DC, then we wouldn't be doing the battery phase test.

Bench tech = The guy caught in between the engineer trying to design something that won't fail, and the user who has designs on making it fail anyway.

Try having outputs short, in a direct coupled amp, that doesn't have D.C. offset shut down protection, see how long your speakers last.

 

[Hand slap]

There's no reason why you can't be both. The best techs are the ones who understand why things work the way they do.
The next time you look at a square wave on your scope first run the output of the signal generator through inductors of various values and then into the scope and see how they affect the waveform. Try some capacitors paralleled across the load too, because voice coils have capacitance as well as inductance.

Will do Rick James, thanks, take care.