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    quick question about LPF and HPF

    so im filling out this form for team toxic bass on a phase box... and its asking for lpf cut off and hpf cut off. im taking it i put 34hz in lpf as thats what i want it tuned to? or am i wrong. and if i was right on the first part what should i put on my hpf cut off







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    Re: quick question about LPF and HPF

    whats a phase box? Or are you talking about a bandpass box which has LPF and HPF?



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    Re: quick question about LPF and HPF

    Lpf and hpf are filters, there's no filter in boxes.....






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    Re: quick question about LPF and HPF

    Quote Originally Posted by nismos14 View Post
    Lpf and hpf are filters, there's no filter in boxes.....

    From what I have read, bandpass boxes provide rolloff at a high frequency and low frequency providing a bandpass filtering of signals. a 6th order will provide a higher rolloff frequency than a 4th order and so forth. frequencies within the pass band are raised for a flatter response in that band.

    but I could have read wrong . Perhaps you can enlighten me on how they work.



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    Re: quick question about LPF and HPF

    You're right, I'm probably just not in the loop about these phase boxes






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    Re: quick question about LPF and HPF

    Order has to do with rate of rolloff, not frequency. There are a lot of things that can be done with bandpass boxes and the overwhelming majority do not have a flat response within the passband but rather accentuate one frequency. Those that do have a really flat frequency response are either really efficient with a really narrow passband (still effectively accentuating a small frequency range) or are fairly inefficient but have a broader bassband.

    The hpf and lpf referenced in the form are high pass *frequency* and low pass *frequency* not filter. The hpf should be the bottom of the passband and the lpf should be the top.



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    Re: quick question about LPF and HPF

    I'm just curious...is the benefit still there if you have an amp/processor that will controll rollofs, q, center frequency, etc? Seems to me that would negate the need for a one of these boxes?



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    Re: quick question about LPF and HPF

    Quote Originally Posted by bikinpunk View Post
    I'm just curious...is the benefit still there if you have an amp/processor that will controll rollofs, q, center frequency, etc? Seems to me that would negate the need for a one of these boxes?

    Perhaps, but that would mean turning the eq up on that frequency you want higher, and making your amp work harder. The bandpass would do it for you.

    You are correct Halo, I meant the rate of roll-off. my english went a bit blurry there .

    as the rate of roll-off is higher, the gain outside the passband drops much quicker than with other enclosures, almost like using active or passive crossovers. Or am I wrong?



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