dc audio m3 8 enclosure

So I've owned my DC 8 for a little while now and love it! Previously I had it in a 1 cuft. 34hz box. They call for a .75 cuft. and I'm wanting to use two of these now Im really drawn on the tuning I want to use... I feel like the 34hz was a tad low because it couldn't get some of the higher notes that where noticeably missing but im afraid If I go up to 38hz Ill lose to much of the lows I love so much... Any input? http://www.dcsoundlab.com/m3-8.html

you probably lost those higher notes because the box was too big for that sub and mellowed out the response of those higher bass notes in a trade off to bring out those lower notes with an 8 inch woofer. if you get two woofers try building the box to spec, .75 ft^3 per woofer, and do a shared port tuned to 34 hz. you will probably get closer to what you are looking for. i know it doesnt sound like much but a whole cubic foot of air is on the big side for an 8 inch woofer even for a ported box. if you think about your typical 12 inch sub could also probably work well in that same airspace or maybe just a tad bit more.

First, let me say that this is a bit late but that's because I just discovered the DC Audio M3-8 and when I did a google search on it this post was in the results. I still thought I could help so here goes. Check out the uploaded image. Whenever I'm choosing an enclosure config for a sub I do calculations on the speaker's parameters using WinISD and these formulae that I got from here. The blue curve is the response of the speaker in your 1 ft^3 tuned 34. It's f3 (cut-off frequency) is 27.03Hz and it peaks at 6.655db, 35.76Hz. The teal curve is manufacturer recommended with tuned 34Hz. The f3 is 27.33Hz and the peak: 5.358db, 36.89Hz. The green is the 38Hz tuning that you were considering but for 1 ft^3. F3 is 29.57Hz with a peak of 8.282db at 39.93Hz. While they will all give good lows the problem with them is that they would be very boomy because of their strong peak and as you can see the response curves are not flat (instead, they're very peaky) so it would be difficult to get a good balance between highs and lows with these enclosures. The gray curve is the optimal based on calculations done using formulae with the T/S parameters which define speaker properties. WinISD and the formula from here give more or less the same results. This enclosure 0.942 ft^3 tuned 24Hz has it's f3 at 20.51Hz. Although there is a peak at 24.37Hz it is only 0.959db and as you can see from the image the curve is much flatter and would allow you to much more easily balance the lows and the highs. If you think that 20.51Hz is too low a cut off frequency then just put on a subsonic filter at 25Hz or 30Hz, whatever suits you. There will be some people who will say that that's too low a tuning frequency but it's not about what people think; it's about what the speaker needs because of it's electrical and mechanical properties (defined by Thiele/Small parameters) and how it will operate in a given enclosure because of its properties. Hope this helps.