If you plan to use it to the absolute limit, I agree.
I've developed a habit to run a frequency sweep to 10hz just to check how bad it is at various levels, I remember some years ago with my 4 x 15" woofers I set them to 20hz on a 33hz box tuning to run them in and sat down for dinner. Talked to my kids about low frequency sound for a bit, after dinner my daughter went downstairs and yelled: "Now I know what sound you where talking about daddy!" And just cranked it up full tilt, kitchen cupboard doors rattling like crazy and plates making a total racket. I ran downstairs and there was no issue. Nothing bad happening, the amplifier could not deliver enough current apparently, was only about 90w power per 2x15" though, but it did make me much less concerned about the whole thing.
I did try and test a bit with 400wpc per 2x15" and it's fine as long as I have a HP filter, tried feeding them 1kw outdoors but that's too much. Cheap drivers, runs out of xmax.
For the DSP setup I use outside on the lawn I do run into trouble and do a 4th order BW at 30hz, but in the house I have no HP filter on any of my systems.
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Sorry about the multiple posts, just wondering how you can reduce group delay from filters at low frequencies without causing significant delays from FIR processing.
Honest question, because I would really like to know how to fix these things with minimum processing delay to get as tight sound as possible for live use.
Well, ofcourse, but if you stick one on the front and one on the back you get both force cancellation and double membrane area. And it's probably cheaper than buying a single long-throw 8" because they're often expensive. Either way, both options give diminishing returns because of restricted box volume etc.
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Could have 1 long throw 8" with 2 longthrow PR's and slap those on the sides, but that's even more expensive.
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EBS == Extended Bass Shelf.
The cabinet and port are sized such that the low end is extended but at a few dB less volume than nominal. The response does not remain flat until it starts to roll off at 24dB/ocatave as it would with a normal ported design. Instead the response decreases a few dB then flattens out again, i.e. shelves, until resuming rollof at 24 dB/octave at lower frequency. This scheme will only work with a sub when the intended high ened rollof frequency is below or at the shelf dip. Otherwise, for full lrange, the low end will be extended but will be 3 dB or so down from nominal.
Maybe the 8inch Wavecor is my best bet then.
I have simulated that with room gain I get a flat response at 30Hz.
Without room gain F3 is 38hz.
Is that good enough for music.
I have simulated that with room gain I get a flat response at 30Hz.
Without room gain F3 is 38hz.
Is that good enough for music.
Probably adequate for most people, not that many modern recordings that have content of significance below 30hz or so.
Excluding bass test tracks, a few movies, some organ recordings and a relatively short list of piano recordings that actually have output to 27hz.
You're not missing that much, there's even a few records that are actually better sounding with a 35hz high-pass.
Excluding bass test tracks, a few movies, some organ recordings and a relatively short list of piano recordings that actually have output to 27hz.
You're not missing that much, there's even a few records that are actually better sounding with a 35hz high-pass.