Does using a low pass on a mid range woofer change the amount of power it can handle?

My question is simple. I want to buy an 80 watt rms woofer (because it’s cheaper) and set it up as the sub on my 2.1 system. If I low passed it will it still handle 80 watts rns or will it handle let’s say half of that for example. I have never used a woofer as a sub before and I have searched the web for so long and I can’t find a damn answer to my question. So does a low pass change the rms rating of a mid range woofer and does having a deeper low pass lower the rms even further? The thing is getting a 10” sub is gonna be way more expansive than the 10” woofer I found for 15 bucks that actually looks like a decadent bank for the buck. So all I want to know is what amp should I use with it and for that I need to know if low passing a woofer lower rms rating and by how much and does lower low passes reduce rms even further. If it’s important the speaker is 8 ohms and an svc.

8 Answers

  • 2 months ago

    A low pass, or any filter, does not change how much juice it takes to burn out a woofers copper coil. It limits the frequencies (TONES) the amplifier sends to it.. Most crossovers set what tones go to what drivers. While this can limit how much work a particular driver tries to do, It has nothing to do with over cranking your volume control. On the other foot, a typical room speaker normally operates at about an average 3 watts to produce a typical room volume ( loudness) So I wouldn't worry about the woofers self destruct maximum wattage unless you are a jerk with the gain control or using it with an oscilloscope to produce pure, constant tones below 100 Hz.

    You might want to check what output (SPL) the driver produces at one watt (within its allotted tone range) from a meter away. You might find it can play very loudly indeed without driving up your electric bill, (still be well below 80 watts average virtually always).

    Just because some huckster sales agent notes the speaker or driver can handle a bazzillion watts doesn't mean it ever will approach that level on actual music real world.It sort of like the same guy selling you a pen guaranteed to write under water and not fly to the moon. Music is pulsive and the wattage going through it is not constant, but varies all over the place.There is usually plenty of time between peak pulses for the coil to cool down. This is perhaps one of the few places where a music power rating means anything.

    It would actually have to AVERAGE more than 80 watts, like receiving a shorted tone, or constant whistle (pure tone) long enough to heat up, to do that. Most speakers are destroyed by shorts, or are mechanically damaged by abuse, like pumping an amp until it went into distortion. Few from voice coils melting out.

  • 5 months ago

    Power handling is limited by heat. It has nothing to do with frequency.

    However, running a small speaker at lower frequencies than intended could put the speaker in a state that approaches or exceeds its mechanical limits.

  • 5 months ago


    The power handling rating given by the manufacturer

    is the final word --- as long as it is legitimate to begin with.

    A filter (crossover) in a speaker system has Only One Purpose:

    limiting the frequency range a driver will reproduce.

  • Anonymous
    5 months ago

    No. The speaker is rated for 80 watts and the crossover network cannot reduce that. It can only raise it since it reduces the power somewhat.

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  • don r
    Lv 7
    5 months ago

    It's either a midrange or it's a woofer. Those are ranges of frequency, not power. If your woofer is spec'd to handle 80 rms watts at 30 Hz, you could. If mounted in a good ported cabinet, your woofer might keep up with the rest of the stock system, though it won't blast out the neighborhood, you might irritate the folks nextdoor. Filters do not change the power of a speaker. Playing more bass may give the impression of power though. What about this; Listen to this speaker on display in the store before choosing it, unless you just feel like experimenting to learn what's what. Just because a speaker is 10" doesn't determine its frequency response or power. The impedance of the speaker will affect how the amp runs it. You're going to have fun for a little while, and learn something. There is no such thing as a *cheap* and *good* system. There's a lot of information you could read- see "". However, diagrams and equations explain much, except actual experience.

  • 5 months ago

    No. Not a low pass filter. Bass carries the most energy. For instance, lets say you have a three way speaker system and the crossover points (a crossover is simply a set of filters) are 100Hz (low pass) and 2,000Hz. If you give it 100 watts of white or pink noise the woofer will get the full 100 watts. The midrange will get around 50 watts and the tweeter will get about 15 watts.

    Also, the difference between a subwoofer driver and a woofer driver is very subjective. The term "subwoofer" has been greatly corrupted by the car audio crowd. A "mid-woofer" is generally a driver that can produce appreciable bass with a relatively low fs but still has a cone and motor structure that can extend into the midrange frequencies without poor linearity or rolloff. Dual voice coils often are the differentiating factor. One can build a very good subwoofer by using a driver sold as a "woofer". I have done so many times.

    I don't know what amplifier you should use. Use your judgement given what I have just told you.

  • 5 months ago

    Sorry for the terrible grammar and words. Typing this on a phone with auto correct. And it only ads salt in the wound that it’s 1:45 am

  • 5 months ago

    I have a Bernese Mountain woofer. They are great, but big woofers don't tend to live as long as mid range woofers

    • Nurgle5 months agoReport

      You're going to adopt a woofer for only a few months? Just wait till you can afford a big woofer then.

      And I don't think its legal to blow up a woofer

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