Jump to content
Sign in to follow this  
rmksledhead

My Bl 12

Recommended Posts

Well after a few months of owning my Bl 12 I've learned that I won't buy a mainstream sub for myself ever again! I also won't ever build a box that isn't as good or better than the one that I built for this beast either!

 

Its only seen a 1200w rms hifonics amp the time that I've owned it and I feel it could handle 2000w with proper crossover tuning. I ended up building a box which after bracing was really close to 2.45ft^3 and tuned to 30hz give or take a hertz(not sure if the port is "exactly" 2.5x12" and "exactly" 31.25" long). It gets much lower than the system in my s10 that is for sure!

 

Although I do love the way it sounds down low, I'm missing the volume i had in the upper frequencies(below 55hz). Its so much different that when I listen to rock I can hardly tell that I have a sub in the vehicle where in my s10 you feel every bass drum kick in your chest. I dont want to blame this on the sub since the enclosure is tuned so low and I still have the stock front stage and HU.

 

I'm in the process of installing some kenwood components (xr1800p) in the doors and powering them with an old pioneer amp i had lying around(gm x524) and I'm replacing the head unit with a AVH2600bt pioneer touchscreen.

 

I really hope that its the front stage making the biggest difference in the way the upper bass frequencies feel and that I'll love everything about the system in my passat better than the s10. I plan on updating this thread when Its all complete.

 

I also finally found a method of inputting parameters into Win ISD that works! I won't say that I regret getting the BL but after seeing how it and the Q compare I would get the Q next time around. Here is a comparison of 5 12" subs around the price of the Bl all modeled in my system on an SPL graph.

 

Win ISD 12" sub comparo

 

Share this post


Link to post
Share on other sites

I forgot to update this thread after taking a couple different steps...

 

First I remeasured the box and found my true volume after displacement was actually bigger than I first thought and the only thing I can think of is I must have doubled the displacement of the driver. Also the port is 2 5/8" across instead of 2.5". After plugging the new numbers into torres I got a tune of 28.5hz and internal volume of 2.68cu ft.

 

So after the xr1800p components and that old dust amp were installed, along with another run of knu konceptz 4ga cca power from the battery, rca's, etc, The sound did get better. The 7" woofers sound great and dish out a good amount of bass down to 50hz and some of the kick was back when I listened to rock.

 

Still, after the components i wasn't as happy with the 40hz+ output of the bl as I wanted to be.

 

Finally (2 days ago) I figured it was time to chop the port length down. Went to menards to pick up a multi-purpose cutting bit for the dremel and hacked 10.5" off the port. Back to torres I get a box volume of 2.88 and a tuning frequency of 32.2hz.

 

My suspicion that the tuning was low was confirmed by running the numbers again and also by how much better the sub sounds on a wider variety of music. (can't listen to decaf forever)

 

Overall I think I'm still going to throw the type r 10 I've got in a sealed box to compliment the bl. I just miss the overall volume I had with the Mtx square 12 ported-type r 10 sealed combo in my s10.

Share this post


Link to post
Share on other sites

I suspect this is part of the reason I was so used to great upper bass volume and never had any low end extension in my s10! The cyan line is the box before cutting the port, the yellow is after and the white is the box my mtx square is in in my s10.

 

Yes, I realize that the spl graph isn't what it will actually be like in a vehicle but it does give you an idea of how different speakers and alignments will sound comparatively.

 

Also, I decided to try a 6th order box instead of adding the type r to the system.

 

Pog8ra9.png

Edited by rmksledhead

Share this post


Link to post
Share on other sites

All of those plots have a lot of ripple and when combined with cabin gain will make it sound like you are missing the top end of the sub stage due to the exaggerated bottom end.

 

You should try and find something that models flatter, or you will be forever stuck with what sound you are describing (without heavy eq'ing...)

Share this post


Link to post
Share on other sites

Yes I totally agree with you... But I would need someone to want to trade me an ethos 12 to get the best of both worlds... and build a smaller box for the ethos.

 

I think my best(cheapest) route is to try a 6th order, mostly for fun, but if it works out I'll just make that box look pretty.

 

Here's the 6th order vs the vented i have and also the box I would build for the ethos

 

bRJb2qQ.jpg

Share this post


Link to post
Share on other sites

That response looks pretty nasty, it may work ok.  Honestly though, 6th order alignments are hard to nail down right.  Depending on how you design your venting and the way the cabin is, cancellation can become a huge issue...

 

It sounds like your mind is set though, so good luck...

Share this post


Link to post
Share on other sites

I wish I could give a sample of how the car sounds now.. NOT a friendly interior to work with when it comes to a flat response. If my head is where it is during my typical driving I have very little bass above 45hz and almost nothing above 60hz, like NONE... move my head 8" any direction and its perfectly acceptable.

 

Coming from my s10 I don't understand it at all. That thing is loud everywhere.

 

If there wasn't a dead spot in the passat where my ears usually are I would be worried about the overbearing upper bass that winisd is showing, but until I try the 6th order I won't know for sure.

 

I buy all my mdf from the seconds bin at menards so its super cheap and I enjoy building this stuff. If it works, great. If not, oh well, It cost me $20 and now I know from experience.

 

Here's the 6th order. Slightly different than what is modeled above but pretty much the same curve. I didn't want to sacrafice much more trunk space than the box I have already does so its only a half inch taller to get the BL to fit inside and 2.25" deeper than the vented box

 

oZkrkt1.png

 

Also, Its my understanding that the closer the tuning frequency between the front and rear chamber, the worse the cancellation is... I've never seen or heard a 6th order in person so I'm just going off how the response curve changed in winisd when I was playing around with different volumes and tunings... Is that generally how it works or should I be looking into which direction to point the ports?

Edited by rmksledhead

Share this post


Link to post
Share on other sites
Sign in to follow this  

×