resonance and sealed enclosures


I was wondering: suppose you have a smallish sealed subwoofer with a resonance frequency of 40 Hz (obviously not up the quality of the things usually talked about here). This is right at the frequency of the low E on a bass. My concern is that the reponse at 40 Hz will be exagerrated. The resonance peak on a sealed sub isn't important when it's 20 Hz or below. Will the 40 Hz resonance really matter?

I am thinking about using this sub for computer speaker BTW.
daniel_newhouse5e69
Sean...We know how you feel about vented speakers, sealed speakers, and even TL, but what is your take on the resistive vent, such as used with great success in the old Dynaco speakers? I tried this once with a box that was a trifle too small for the driver, but didn't see much effect, good or bad.
El: I don't have a lot of personal experience with this type of design as compared to others that i've discussed, which for the record, is called an Aperiodic or "Vario-Vent" by some. From what i have heard, experienced and read about these designs, i like it better than most commercially available ported and passive radiator designs. Like anything else though, one would have to carefully select the proper box / driver combo to obtain optimum results.

As a side note, there was a commercial speaker designer that was posting on AA under the pseudonym of "Mr Bigglesworth". Whoever he was, he wanted to remain anonymous but at the same time, tried to share his experiences and educate the masses. When it came down to it, he stated that if one were do all of the measuring in the world and their goal was to achieve the highest levels of linearity possible, a sealed and stuffed low Q box would be what they would end up with. I asked him what his thoughts were on Aperiodic's and Transmission Lines and he referred me back to the sealed box along with an explanation why he had those thoughts. Given that i was already on the same page that he was, i didn't need much convincing. I was just looking to compare notes with someone inside the industry that didn't have a reputation to uphold or specific product to market. Sean
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Push / Pull lowers distortion, increases power handling, faster transient response, lower impedance peak at resonance, improved power transfer characteristics, etc... If properly implimented, it can be quite beneficial. I'm using a dipolar push-pull arrangement for my own personal subs. The dipolar pattern reduces standing waves, which further improves the linearity of in-room response. Problem is, you've got to use twice as many drivers, resulting in a lower impedance, much higher cost to build and the need for a much sturdier amp. Sean
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