The design is pretty forgiving on the driver choice. All the mentioned drivers would work. If it's for use at home the 2226 would be a good choice (for PA use I would only recommend the 18" ).
Making Cubo Sub smaller will lift the low frequency roll off up.
Having said that. The JBL 2245 has a Fs of 20 Hz and decent Xmax, you could get it to go lower then Cubo Sub in a reflex cabinet, at the cost of output but as you say that isn't your primairy concern. In fact if you have a normal sized bed room, I'd say the 2226 could be put in a tapped horn tuned at 30 Hz but in a smaller enclosure (again at the cost of output).
I downloaded Hornresp, but I don't know how to use it and I don't know how predictable the results are. I have been reading some people report they are not super accurate.
I'm not too concerned about output, but I did think that this cubo sub would have less distortion than a BR because it has less (or no) port noise and the woofer would have less movement at a given SPL. Are my assumptions incorrect?
You're indeed correct that port turbulence is lower and cone movement on average will be less for a given SPL in Cubo Sub with regards to a reflex cabinet based on the same driver specs.
However the speed of the air in the port of any reflex can be calculated and thus you can choose the port size in that way that the air velocity keeps under 17 meter/second at the maximum desired power level (for home use that is sufficient).
I do not know of many people that are concerned with distortion due to cone movement as long as it's within the range of the stated Xmax. I know they have a valid point but below 100 Hz, I doubt it would be of note, when used within reason.
Oh boy. I'm confused, look ------> smiley29 or maybe like this also ----------> smiley24 and perhaps a little :think:
I think I will have to figure out how to use Hornresp and maybe model some ported enclosures also. I need a horn that is roughly 1215 x 510 x 770 mm. If it's shorter than 1215 mm I think my kids will get on it and then on my main speakers and then my computer and tv and etc. Or bass relfex might be good also. I like how the cone excursion is limited at tuning, but I don't like the way they sound. I have read that when designed right they sound just as good as a sealed with a Qtc at or near .5, but I haven't hear one that is as good.
You can read this guide to WinISD and Hornresp for starters. If going the reflex route you'll need WinISD Pro for telling you the air velocity in the port.
Hi Cubo, Hornresp is now capable of simulating the port velocity.
From the SPL response window, then select the Combined Response from the Tools menu, and enter a blank, for the port only output.
When the Port SPL response is displayed, then select Particle Velocity from the Tools menu.
WinISD is a good start and easy to learn but Hornresp is capable of more accurate results.
A comparison of WinISD and Hornresp here, http://forum.audiopsychosis.com/viewtop ... 79&start=0
I am now using Hornresp for all my reflex port designs. smiley20
Unless however some significant changes have been made between 28.7 and 28.9, personally I would still be inclined to use WinISD Pro for (about just) that purpose.
Call me old fashioned but my mind needs several time periods to adjust between WinISD's all-is-smooth-and-round and Honrresp's all-is-very-peaky responses. Measurements have shown me the result is often in between...
I know that 30 m/sec is an actual good guideline for PA-purposes and 17 m/sec is a good guideline for home applications in WinISD Pro. I do believe that these exact figures need to be re-evaluated for HR.
Luckily I'm experimenting with a ported Cubo enclosure at the moment so I'll have time to evaluate