First time DIY

[Rodtay]

This is my fourth time trying to post this so I hope it comes up. I am building a 2 way system which consists of a Dyaton 8" series 2 woofer and a Dayton 1 1/8" silk tweeter. The crossover is going going to be 2nd order but I don't know if I should use Linkwitz-Riley, Butterworth, or Bessel. Can someone help me out. I don't have the means to run a calculated program but 2500 hz's is a ballpark crossover point. I'm going to use a ported box tuned to 43 hz. What size port do I need? When I searched Parts Express for the woofer, it was found to fit in a 1.11cuft box but BOXPLOT showed .67cuft. Can anyone help me on this. Also, what would be the best stuffing to use? This speaker doesn't have to be perfect I do enjoy great sound. Any comments or suggestions would be greatfully appreciated. Thank you.

[navin]

unfortunate. ususally the guys are more responsive.

1. 8" and 11/8" can work but you might get some beaming in teh 1-2k range.

2. I prefer L-R but now kowing teh drivers you are using i can be sure. download LSPCAD it will give you some ballpark numbers.

3. if you can post T/S specs someone can figure out box size. If I were you I'd consider 1.1 cu. ft. 8" woofers usually require 30-40 liters. (I said USUALLY). you can always make a box smaller. even after it is finished.

4. see if you can find polyfil used for pillows will suffice for your needs.

5. are you looking at a sealed or bass reflex box? stuffing and box size will change quite a bit.

[Rodtay]

I would be using a ported box design. It's going to be a 1.15 cuft enclosure. I don't have any means of getting the T/S parameters. What site can I download the LSPCAD from. What would be that best design that you would pick for a beginer( using something larger that 5.25" woofer)?

[wintermute]

Originally posted by Rodtay
I'm going to use a ported box tuned to 43 hz. What size port do I need? When I searched Parts Express for the woofer, it was found to fit in a 1.11cuft box but BOXPLOT showed .67cuft. Can anyone help me on this.

Hi Rodtay,

I think that you will find that boxplot and some other programs will give you the volume that gives the "optimally flat" response for your speaker. I've used boxplot, speakerworkshop and some others, don't be afraid to change the tuning freq, or volume of the box in the program to see what it does to the response curve. After all it's only a simulation

I personally would rather play around with the volume and tuning freq and end up with a response curve with maybe a 1/2 db dip in it, if it means the simulated -3db point will be 5 - 10 HZ lower.

Another thing that can make a big difference to how the simulation turns out is the addition of some series resistance, (less than one ohm), this is something I have only played with in simulation, not in practise, so I'm not sure what the real implications/practicalities of series resistance is (apart from probably reduced sensitivity)

I used either speaker workshop or boxplot to work out the port length in my current speakers (two 70mm dia ports). It worked a treat.

BTW port diameter and length are both important, too smaller dia and you may get port noise (wind rushing noises in the ports) the dia + the lenght + the box volume will give you the tuning freq (using the correct formula).

Wintermute.

[navin]

Rod, use google

[bob2010]

Rod,

check the link below, just what you want. I've read in the PE
forum that their very good for the the money.

Bruce


http://www.wadsnet.com/~dtenney/dayton_8MTM.htm