Bandpass Subwoofer Design

Hi everyone

I've made a fair few sealed and vented boxes over the years for a variety of speaker sizes, but haven't made a bandpass box yet.

I've uploaded the WinISD Pro files i've come up with, for a Kicker 15" CVR sub and a ~130 litre box, and I'd like to know if i'm doing things correctly here

http://www.fileden.com/files/2009/4/1/2388202/Kicker CVR152.wdr

http://www.fileden.com/files/2009/4/1/2388202/Kicker CVR152 bp.wpr

I forgot to work on the ports! I think the port velocity of the front chamber would be fine with a second standard port added, so the front port velocity would be ~23.5m/s, and I think the rear port velocity is fine as it is. I'd probably end up making rectangular ports however, if I was to make this box.

I tried a few different 12" and 15" subs, and the Kicker CVR 15" seemed to give the best response in a box this size.

I'd appreciate any input in either my box design, or perhaps another sub which could offer improoved sound quality with a similar spl, or a higher spl with less power... or possibly both Without using a larger box that is, say 150 litres maximum, including subby and port volumes.

 

Yep, i'm planning on porting both the front and rear chambers

The driver parameters I used are in the first .wdr file I linked, and some of the values are a little different to Kicker's specs, due to WinISD insisting certain relationships between all the TS specs I've always just accepted this in the past. As for Kicker's quoted T/S specs for the 07CVR152, the're on page two here:

http://www.kicker.com/sites/default/files/CVR_0.pdf

I like to play almost everything, depending on the mood. Old stuff, classical, rock, metal, techno, R&B, rap, whatever. My aim is to have a clear & smooth response with as small a size, trying not to use alot of power, and 120db would be plenty for me. I dunno what car this is going to go into, i'm just playing with designs for know, probably because I haven't made any subby boxes for a few years

According to WinISD Pro available free here:

http://www.linearteam.dk/default.aspx?download=winisdpro

The box I designed with the Kicker CVR 15" would only make up to 117.7db @400w, but I think it was a broad response, as it was over 117.5db from 40-50hz, and over 113db from 29hz-76hz. At 300w it hit 116.5db which is enough, i'd probably go with that. I thought the delay times were good, gradually getting to a worst of 20ms, and the cone excursion didn't go over 9.5mm @400w... but all this is according to WinISD, which has always seemed to be very accurate at designing sealed and vented boxes. What software do you guys use?

Those old Orion's sound interesting Was it a peaky response to get such a high spl from one 12? They must have been efficient! I also tried making boxes from AE 15" which had over 94db effeciency, but I couldn't get a smooth response out of them from <150 litre total bandpass enclosure.

 

I tried simulating the L5 and L7 in a bandpass Connerray2010, but they needed around ~150w more than the CVR subs for the same SPL iirc, as they are a bit less efficient. According to WinISD, the L5 and L7 can outperform the CVR subs in terms of SPL if you give them some more watts, as they have a greater excursion ability.

In either case though, I couldn't get the L5 or the L7 to respond as smooth/flat response from ~30-80hz, and they weren't as quick/had worse delay times - all of this is under the restriction of 150 litres total however.
I haven't tried the solox, a bit pricey and way more power than I want.

That's an interesting box Ranger SVO, is that with a Kicker CVR 15"?
And what spl did you get, and with how many watts?

So what criticism's can you guys give me about my box?




What other brands/models of sub should I be checking out?
That's still a nice SPL for one 12" Viking... I'll have to try some boxes with an Orion in them!

 

I've been playing with the Kicker S15L72 Connerray, and I can't get a nice response out of it in bandpass, unless I make the box huge, like ~250litres.

WinISD reports 120db@57hz 400hz, from a 100 litre vented box tuned to 26hz, but it's fairly peaky, down to 115db@40hz, and 110.9db@30hz - some like it like that, but not me cos then most bass beats will start to sound a little similar, which just makes everything get boring and annoying to me. I like a broad/smooth response, so the subby will only amplify the bass.

The S15 delay gets rough in a bandpass, alternating from quick to a little sloppy across the bass range, but in the vented box it's fairly quick. It seems to be a good sub for people that want a bit of a peaky response from a med/small box. In a sealed 100 litre box, it was still peaky, and only about 2db down, with a very quick response all the way down low.


Ranger SVO, you mention that these Kicker subs aren't the best choice for a bandpass box. Which subs do you reccomend I try?
And what do you think of WinISD? I think i've used Bassbox years ago, would have been a way older version.


TheViking, I wanted to have a smooth response down to 30hz at least, as I like those ultra low earthquake deep rumbles as much as any other bass. I was actually expecting that maybe someone would say the box I designed was too small, and didn't go down low as it could.

I also just tried one Orion in a bandpass, the XTR152, and didn't get a nice response out of it, performed similar to a solobaric for me, but i've only tried that one so far. Can you also reccomend any subs for me to try and get a nice response out of a small box?

 

What I like about the Kicker CVR15" in bandpass, is that it can get a similar spl as vented, but it can go a little more deep, instead of dropping off sharply at ~35hz, and in a high gain vented the cone excursion goes nuts down low, so a high pass filter would be needed, further reducing a bit of the deep rumbles.

Not a big deal I guess, but I've always wanted to make a bandpass box anyway
I've made quite a few vented and sealed boxes over the years, for everything from 4" up to 18" - 18" was my favourite, that thing went deeeep It was ~220 litres though

I don't mind sacrificing spl to have a nice wide response and a small/med box, ~120db is enough for me.

Tell me Viking and Ranger, what other subs should I try having a play with?