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My current amps don't have clipping indicators, but I would notice distortion before I reached driver limits. Then again my normal listening levels varies greatly so I felt a bit more power was in order.
 

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How does a speaker, any speaker know the difference between a clean signal and a distorted one? If the speaker is still oscillating then it's shedding heat regardless of the signal it's getting.



I see what you're saying, but I think of distortion as just that. I don't lump clipping into that because one is signal and the other is power. Related but a distorted signal is not necessarily clipped. Agreed that clipping adds power.
I'm definitely just chiming in for the sake of learning. I'm not the best at conveying the thoughts in my head so I'm really using words out of context in a big way :)

I had read another paper sometime back, don't recall where, that stated it's crucial to keep a clean signal going to the coil. So when I refer to distortion I was trying to imply a clipped signal.

So here's where I'm getting mixed up between the two sides...A clean signal can overwhelm a coil but so can a clipped signal....is all this coming down to the same thing as always; make sure you're only feeding the speaker what it can handle and use filters as needed? That's the art of this whole thing. Balancing install needs with what you have or will have vs. what you like. Holy crap...I get burned out reading this stuff sometimes.

So what everybody is getting into is whether it's the amp's fault or not? Hrmmm. Well this is probably where I just start watching again. I haven't burned one up yet. So I'm applying something right.
 

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Personally I've always matched power as close as possible, but this time I'm going for the extra headroom. Nothing worse than smelling your a/b amp on a long drive during the summer (I do push it to it's limits often). Haven't blown drivers or amps in a long time, but I don't like reaching power limits so soon. Will I reach driver limits now? Hmmm I don't know, but I'm hoping amp distortion won't be an issue. Two MRX-F30 on fronts (1 bridged on midbass), and a MRX-M100 on sub(s). Hoping this cures the headroom & heat issues, plus opens the door for more driver options. Perhaps I'm going in the wrong direction so I'm going to stay tuned to this thread.
 

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I wish I had the money to overpower the piss out of everything....

If you ain't flickering the clip light, you are wasting money on too much power.
Ahh, the good old days of DJing with the Peavy CS amplifiers that felt like they weighed 100 pounds each. I used to run them with the VU meters bouncing into the DDT light.
 

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I'm definitely just chiming in for the sake of learning. I'm not the best at conveying the thoughts in my head so I'm really using words out of context in a big way :)

I had read another paper sometime back, don't recall where, that stated it's crucial to keep a clean signal going to the coil. So when I refer to distortion I was trying to imply a clipped signal.

So here's where I'm getting mixed up between the two sides...A clean signal can overwhelm a coil but so can a clipped signal....is all this coming down to the same thing as always; make sure you're only feeding the speaker what it can handle and use filters as needed? That's the art of this whole thing. Balancing install needs with what you have or will have vs. what you like. Holy crap...I get burned out reading this stuff sometimes.

So what everybody is getting into is whether it's the amp's fault or not? Hrmmm. Well this is probably where I just start watching again. I haven't burned one up yet. So I'm applying something right.
Exactly. It's ALL about power and not exceeding your drivers' limits.
 

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DDT is limiting, damn good limiting at that. Beats the fuck out of Crown's ODEP... that's horrible shit.
Gotta love Jack Sondermeyer and his bullet proof designs! I attended two of the Peavey Advanced Sound Reinforcement 5-day seminars in Meridian Mississippi back in the 90's - got to meet and learn from all kinds of awesome engineers @ Peavey. They really do get a bad wrap IMO (sometimes they might deserve it, but only from a "cheap is good / poor musician" angle). I still despise their lack of any sub-40Hz response in most of their subs :mean: When I asked one of their PA Speaker designers why they simply cut holes in a baffle and call it a "Port", he stated the 3/4" thickness of the baffle WAS the port length!!! :eek: This was for an SP2 "Main" speaker, but still - a 3/4" long port???!!!!??? I guess it works for their relatively high f3/fb response in exchange for extra efficiency...

I'm still rocking some older SP2XT's and Impulse200's, and have a few CS800x's in storage.


Back on topic: I like how MarkZ recapped this - that should clear up anyone's misunderstandings about clipping and RMS power IMO.

And his "[the caveat here is when tweeters are on passive crossovers... then it's a different story]" statement is spot on wrt my previous comments on how/why clipping can kill tweets more easily than a woofer (in a passive full-range system).

:cool:
 

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While you were in Meridian did you do any partying with Max? He's a good time. I spent a bunch of time down there too. Did a LOT of peavey service and was one of the few that did mass repairs on the DPC stuff. Can still repair those damn things in my sleep.

It was not uncommon to use a "hole" for the vent. Hell, I designed an enclosure recently that never transpired that had just the same thing. Looked damn good on paper too.

Not many pro subs go much below 40, the Q-Wave stuff does now.... Not much below. Hell, the SP series subs did not get much below 50!

I worked a bit in the field development of the BWX series. Broke 4 at a time without the coil looking anything but brand new. Then they got the suspension issues worked out :D
 

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OK - A little more OT!
While you were in Meridian did you do any partying with Max? He's a good time. I spent a bunch of time down there too. Did a LOT of peavey service and was one of the few that did mass repairs on the DPC stuff. Can still repair those damn things in my sleep.

It was not uncommon to use a "hole" for the vent. Hell, I designed an enclosure recently that never transpired that had just the same thing. Looked damn good on paper too.

Not many pro subs go much below 40, the Q-Wave stuff does now.... Not much below. Hell, the SP series subs did not get much below 50!

I worked a bit in the field development of the BWX series. Broke 4 at a time without the coil looking anything but brand new. Then they got the suspension issues worked out :D
"Max" rings a bell - it was in the mid 90's. Our regional Peavey Rep came down there with me - can't remember his name ATM. I remember Marty McCann (spelling) giving most of the lectures. Spent a lot of time in the fish bowl and auditorium jamming, too :)

Agreed on the SP118 subs - useless below 50Hz :) Their BW suspensions always seemed to be a limiting factor to me, too. The coils can take the power for sure, and they make a killer "Woofer" - but Peavey makes their compromises - they rob Peter (low bass) to pay Paul (efficiency and low cost). I much prefer my JBL 2241G's where Peter and Paul both end up rich (by robbing my wallet!) :p Peavey's BWX and Low Riders seem to be a step in the right direction. It's cool that you were involved with their development IMNSHO...

Back to the "Power" talk :smash:

:cool:
 

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Just a closing article on the subject matter for those looking for more clarity. Where I first learned about it, as I am sure many others. Sourced from A2000 tech briefs:

http://www.monsterproducts.com/mpc/stable/tech/A2420_Some_Facts.pdf
Odd - I'm not sure if I agree with all of R.C.'s findings with regard to clipping and how the energy is dispersed through the octaves. He appears to be talking about clipping a single low-frequency sinewave, and is not taking into account clipping complex full-range waveforms. He seems to suggest that clipping a full-range system WILL NOT blow tweets - but we know that is not the case.

JBL certainly states otherwise:

http://www.jblpro.com/pub/technote/lowpower.pdf

I dig and respect R.C. and all, but I'll believe JBL/Harmon (and my own Live Sound experience) well before some car audio buff :)

And even though the clipped harmonics are distributed throughout the frequency range, when you clip a sub amp that's actively crossed, ALL of this energy still goes to the Woofer's coil (the woofer has no passive x-over to filter this energy out). Plus the much higher "duty-cycle" of the clipped waveform further increases RMS Power...

:cool:
 

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That makes more sense IMO. So it's mainly that the full-range amp can keep increasing the HF content's power (since it is already relatively small compared to the bass) when the user is slamming the low-frequency spectrum into clipping. As long as the woofer can handle the total RMS heat of the clipped amp (generally a max of 2x clean rated RMS power), the woofer will keep on chugging just fine (but sound like ass). That combined with the small increase in harmonics due to clipping the woofer, and your tweets are toast just as JBL mentioned above...

:cool:
 

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Yup, just wanted to toss it in there.

Peeps gotta understand that the examples of clipping that are shown are GROSS examples, not a flicker or a waveform hitting the rail real quick like but rather SLAMMING the rails.
 

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Odd - I'm not sure if I agree with all of R.C.'s findings with regard to clipping and how the energy is dispersed through the octaves. He appears to be talking about clipping a single low-frequency sinewave, and is not taking into account clipping complex full-range waveforms. He seems to suggest that clipping a full-range system WILL NOT blow tweets - but we know that is not the case.

JBL certainly states otherwise:

http://www.jblpro.com/pub/technote/lowpower.pdf

I dig and respect R.C. and all, but I'll believe JBL/Harmon (and my own Live Sound experience) well before some car audio buff :)

And even though the clipped harmonics are distributed throughout the frequency range, when you clip a sub amp that's actively crossed, ALL of this energy still goes to the Woofer's coil (the woofer has no passive x-over to filter this energy out). Plus the much higher "duty-cycle" of the clipped waveform further increases RMS Power...

:cool:
IMO you are misinterpreting what RC is saying. He said it is seldom the case, implying infrequent occurrence, not omission of occurrence. Likely due to his implied assumption of proper application. Nevertheless, The Rane article and JBL articles agree with exactly as what Richard's data indicated...that excessive power from an x level of clipped signal, can damage tweeters. RC just seems to assume that the tweeter will be properly applied and set up in a system, so there is no reason to experience full amp saturation.

Rane and JBL have an interest in expressing the information in the manner they did. I don't see the interest for RC. Everything in the tech brief if reproducible and verifiable. So are the other white papers, but they are generalized discussions where RC provided more specificity with his conclusion.

I've never had a problem with smoking tweets and I set my systems up with clipping every time.
 

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That makes more sense IMO. So it's mainly that the full-range amp can keep increasing the HF content's power (since it is already relatively small compared to the bass) when the user is slamming the low-frequency spectrum into clipping. As long as the woofer can handle the total RMS heat of the clipped amp (generally a max of 2x clean rated RMS power), the woofer will keep on chugging just fine (but sound like ass). That combined with the small increase in harmonics due to clipping the woofer, and your tweets are toast just as JBL mentioned above...

:cool:
I don't see how that's possible if your tweeters have proper filters in place. Again, if you are fully saturating the channels that feed your tweeters, creating an excessive clipped state, then this only seems to point to inadequate application.

If you're not clippin' ur just trippin'. lol
 
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