BK XXLS400 question
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but surely that could overpower the driver?
or
has Peerless under rated the RMS of the driver? because I've been reading that this driver performs well at 500w+
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Wouldn't have thought so. The guys at BK electronics have built subs for some years now (& been the OEM for MJ Electronics & REL) Any prototypes should've been rigorously tested before being released.
TBH you're better off posting this question in AV forums, AFAIK one of the guys who worked there used to post on there, he sent me a trust message asking if I wanted to buy one of their subs after I bought the last sub I owned.
It is more difficult to overpower a sub as such in a sealed enclosure. The smaller a cabinet, the more power the driver will require.
depending on the drivers mechanical limits of xmax and xmech, these determine the power it will take and the frequencies it can physically produce as well as certain other parameters which will determine its ideal cabinet size
So you are in a far better situation having too much power and not needing it as opposed to needing more power and not having it. The sub will suimply draw the power if it needs it. If calculated that sub will draw too much power and reach past its limits of excursion - I believe a High Pass Filter will be needed, but as said, this is far more likely in a ported enclosure.
BK have been in the game for a long time and produced subs for the likes of REL and others, so I'm sure they have a good idea about what works best with their drivers
depending on the drivers mechanical limits of xmax and xmech, these determine the power it will take and the frequencies it can physically produce as well as certain other parameters which will determine its ideal cabinet size
So you are in a far better situation having too much power and not needing it as opposed to needing more power and not having it. The sub will suimply draw the power if it needs it. If calculated that sub will draw too much power and reach past its limits of excursion - I believe a High Pass Filter will be needed, but as said, this is far more likely in a ported enclosure.
BK have been in the game for a long time and produced subs for the likes of REL and others, so I'm sure they have a good idea about what works best with their drivers
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Generally Speaking this is true, but there are many different drivers. Sealed cabinets are lots smaller than their ported counterpart
The amp is over powered because if you drive an amp near its limits (i.e in this instance 175w) then it will create a lot of heat and not run effeciently, this also leads to distortion and a generally unpleasant sound. This is when you get amplifier clipping.
So having a more powerful amp than the sub can take is the only option for an efficient and clean way to give it power - otherwise it leaves a recipe for disaster when you hit that moment you're waiting for in a film with the big bass.
thanks for explaining mate. I am understanding what your saying.
1 thing tho how would u know how far u can turn up the volume before it overpowers/damages the driver?
I think you might be mistaking the way the ordinary speakers can be over-driven and thinking the same applies to the sub. It would be very difficult (though not impossible, theoretically) to overdrive the sub.
The sub has its own amp, and that amp is designed to drive the speaker in its enclosure. So the system is all designed to work together.
The signal source is most likely the low level subwoofer output on a phono/RCA connection. So you're not driving the sub with the same signal that goes to the centre and surround speakers. The amp's subwoofer output can't exceed a certain level. The maximum signal level will be around 1/4 of a volt. That won't be reached unless you run the amp at maximum volume and set the channel balance for the sub at +12dB in the speaker level settings. Even then you'd have to set the sub's own volume control to maximum. Whilst it would be possible to do all of these things the sound would be so out of balance and bass heavy as to almost unlistenable. If you have a set-up mic with the amp then it's very unlikely that the auto set-up routine would allow you to get things this out of whack.
If your connection is high level via the Neutrik Speakon connector wired back to the amps speaker terminals then it's still unlikely that you could overdrive the sub. That input is buffered (reduced in level) so that the sub's own internal amp receives the equivalent of a low level phono signal.
The only real risks are you purposely setting up to overdrive the sub, or playing a sub torture test track at high volume straight from cold. Why are you so preoccupied with overdriving the sub anyway?
ok.
I have the sub connected from the low level connection straight to my pc sound card sub output. the other 5 channels from my pc sound card go to my amp. it works well that way has I can everything from the pc. but the reason why I was worried if the driver is 175w but the amp is 400w I thought because the amp can handle more power than the driver if u up the volume to much the driver would be overdriving...
anyway now i'm more confused. I received a reply be from BK.
if that's true then i'm confused because you guys are saying it's not good for a amp to run near it's rated has it can create a lot of heat and not run efficiently.
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Caporegime
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As lucid stated, the sub has its own amp and receives an unamplified signal. So the internal amp will power the speaker in the sub with the power it needs, and as they are designed to work together, during your normal listening it is very difficult to overpower the sub.
You should worry about matching the Ohm rating between the amp and speakers than anything else.
You should worry about matching the Ohm rating between the amp and speakers than anything else.
Oh for the love of God... You're worrying about stuff that really isn't worth the time and effort.
It's really simple. Think of it like this. You buy a little car with a 1L engine. It struggles to get past 80 and 0-60 takes an eternity and there's sod all mid-range acceleration. Now compare and contrast. You buy a big ass car with an even bigger ass engine. 0-60 happen in 6 seconds and the car is restricted to 160MPH but is capable of way way more. Which is the more pleasant to drive. Which one has the power to enjoy the road and safely overtake without a second thought. Hmm? It's called headroom. It's a surplus of top end power that ensures loads of low end and midrange grunt which is, let's face it, at the speeds most of us spend our lives driving at. Just because a car is capable of doing 160+ MPH doesn't mean that from the moment you turn the key you have to drive at 160+ MPH everywhere you go.
It's the same with amps in subs. You put an over rated amp in the sub so that at the sort of typical volumes you'll listen at, and right the way up to reference level and above, then there's still plenty of power in reserve. A surplus of clean power is far better than running an amp at near it's max level where distortion rises exponentially. If it helps you get the idea then think of the sub as electronically limited to that it can't exceed the speed (volume) limit set by the manufacturer.
Now, for the love of Mary Joseph and the baby Jesus, stop fretting about something that is TOTALLY POINTLESS!
You want to worry about something then try this on for size. Think about the next time you're in a car driving along a fast country lane. It's national speed limit and you're doing 50+ MPH. You're passing cars coming the other way. They're going 50+ too. Your combined closing speed is 100+ MPH and the only thing between them and you and certain death in a head on collision is a strip of white paint 2mm thick. Get your head round that!
It's really simple. Think of it like this. You buy a little car with a 1L engine. It struggles to get past 80 and 0-60 takes an eternity and there's sod all mid-range acceleration. Now compare and contrast. You buy a big ass car with an even bigger ass engine. 0-60 happen in 6 seconds and the car is restricted to 160MPH but is capable of way way more. Which is the more pleasant to drive. Which one has the power to enjoy the road and safely overtake without a second thought. Hmm? It's called headroom. It's a surplus of top end power that ensures loads of low end and midrange grunt which is, let's face it, at the speeds most of us spend our lives driving at. Just because a car is capable of doing 160+ MPH doesn't mean that from the moment you turn the key you have to drive at 160+ MPH everywhere you go.
It's the same with amps in subs. You put an over rated amp in the sub so that at the sort of typical volumes you'll listen at, and right the way up to reference level and above, then there's still plenty of power in reserve. A surplus of clean power is far better than running an amp at near it's max level where distortion rises exponentially. If it helps you get the idea then think of the sub as electronically limited to that it can't exceed the speed (volume) limit set by the manufacturer.
Now, for the love of Mary Joseph and the baby Jesus, stop fretting about something that is TOTALLY POINTLESS!
You want to worry about something then try this on for size. Think about the next time you're in a car driving along a fast country lane. It's national speed limit and you're doing 50+ MPH. You're passing cars coming the other way. They're going 50+ too. Your combined closing speed is 100+ MPH and the only thing between them and you and certain death in a head on collision is a strip of white paint 2mm thick. Get your head round that!
This sums it up. Stop worrying.
I was just wondering. ok hence why I asked. no need to get funny about it..
going by BK reply they saying the driver is 400W rms. so it won't be like what your saying above?
At the end of the day what does it really matter? Driven cleanly, most good speakers will handle way in excess of their RMS rating. It's also academic anyway. The sub and amp are matched. So it's not like you're going to change either the sub plate amp or the driver, is it? So again, what does it really matter?
I already said I was just wondering. ok hence why I asked... i'm interested in things like this.
there's a lot of pointless threads on this forum but they still ask.
Soldato
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The peerless drivers are rated by playing a tone through them for 100 hours continuously. I dont know if its white noise or a specific frequency, having a hard time finding that info and its quite important .......
but anyway, peerless drivers are pretty conservatively rated and as others have said, its better to have more clean power on tap than pushing an inadequate amp in to distortion and risking fried voicecoils etc.
Power ratings, even RMS, shouldnt be taken at face value. Often drivers are rated only at a specific frequency and in a specifically tuned box. for instance, get a power meter on that sub and see how much power it needs before the cone is hitting it's end-stops at 20hz. It probably wont be anywhere near 175w RMS..... that's quite normal however.
Short version: trust BK to match the amp and sub, even if the monkey who replied doesnt know anything about the drivers, as they've been doing it for years and they are so highly regarded for a reason. just enjoy the sub
but anyway, peerless drivers are pretty conservatively rated and as others have said, its better to have more clean power on tap than pushing an inadequate amp in to distortion and risking fried voicecoils etc.
Power ratings, even RMS, shouldnt be taken at face value. Often drivers are rated only at a specific frequency and in a specifically tuned box. for instance, get a power meter on that sub and see how much power it needs before the cone is hitting it's end-stops at 20hz. It probably wont be anywhere near 175w RMS..... that's quite normal however.
Short version: trust BK to match the amp and sub, even if the monkey who replied doesnt know anything about the drivers, as they've been doing it for years and they are so highly regarded for a reason. just enjoy the sub
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Caporegime
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For the majority of the population in their regular living rooms, the XLS400 is more than plenty to fill the room with bass. I have mine on what I consider to be normal listening levels and my neighbours can hear it ! If I were to really push it, there is more chance that the windows would come off the wall before the actual sub blows up.
The XLS400 is a beautiful piece of engineer and workmanship, buy it with confidence.
The XLS400 is a beautiful piece of engineer and workmanship, buy it with confidence.