Compound loading 6th order quarterwave "Super Planar" horns and pipes concepts/builds

TPCH12i_BILsim.jpg


Simulation vs in car measurement. The microphone was close to the windshield at the passenger side. 0,3 volt from the amp output.

YouTube

A video showing some rebassed music with strong content around 25Hz which is 5 Hz below tuning.

It was ear deafening to sit in the car while playing bass heavy music with only 500 watts.
 
TPCH-_H-dist.jpg


Distortion at 0,3 volts measured in car.

O.3 volts into the speaker? Seems a bit low. What does it look like at 2.83V and higher? I think it would be interesting to see how the linearity and "distortion profile" changes as input voltage is increased, but it might be best to test that out of the car. For my last few subwoofer builds, I upped the input until the in-band THD just exceeded 10%, then backed off the input in 3dB steps, measuring FR and THD along the way.

It's a pity that FRD doesn't have a means of stacking THD graphs like it does for FR graphs...



cracked.jpg


Crack in the windshield. It kept growing today when we tested the bass.

Well, that's unfortunate. Installing a "stripper pole" in the car (basically a reinforcement to prevent the roof from flexing too much) might help prevent too much bending force being put on the windshield, but it looks like it might be a bit too late for that.
 
Barnaby's Paraflex build is amazing. I'm leaving a link so you can see more projects!

Morgan, you're slacking on the updates man!

YouTube



Bp1Fan ,
Hehe:p , yes, it is true .... I have been trying not to draw too much attention to this discussion until i get the issue with the image hosting worked out (most of the photos won't display at the moment) ... I have been talking to one of the IT guys down at DIYaudio about it, he said they should be able to address it soon ..

That is Barnaby's build featured in the Youtube video, it is actually a Paraflex (not a Tapped Horn) ......

Barnaby told us that at the time he just wanted to refer to it by a name that more people could relate to, so that is why he called it a Compound Tapped Horn instead of Paraflex .. ....

If you want to see a bunch of the new Paraflex and Super Planar 8th builds just check out this link , and be sure to expand the comment section by clicking on "view previous comments" and have a good look at it all, there is much to see! :happy2:
 
Last edited:
Oh yeah! I like it.
What´s the turning point when PA drivers start to beat those "low effiency" car subs?
above 40-50hz?

Manninen,
In this case with Barnaby's Paraflex his B&C iPAL drivers are dominating as far down as the low 30s .... They are not typical PA drivers though by any means .... The Paraflex really makes good use of the extreme amount of effective motor force that the iPAL 18" drivers have to offer ..... A freakishly fantastic combination!
 
The BD4 12" looks to be a good candidate ... Or the DDX 12"

Would Audiopipe bd2 18s work in these enclosures?


Etocynned,
The B2D 18" probably doesn't have nearly enough motor force in relation to it's cone area in order to be a good performer in these highly demanding compound loaded QW designs....

If you are a big fan of Audiopipe brand subs then you could consider using multiple BD4 12s because two of them would be equivalent to a decent 18" subwoofer and would have enough effective motor force to get the job done in a Paraflex:)

As an alternative there is the Skar DDX 12" which has now proven itself to be an excellent low cost candidate for usage in Paraflex cabinets (measured by multiple users now) ......... Four of the DDX 12s wouldn't cost very much (compared to some Car Audio 18s) but would deliver great output in a Paraflex tuned as low as 30hz (that driver prefers tunings in the 30hz to 40hz range) ..

The Skar DDX 12" has more effective motor force than any other driver that we have found in it's price range, even after accounting for Lossy Inductance (verified with both Dayton DATS2 and the Smith & Larson woofertester2)...
 
Last edited:
BP1Fan ,

Good to know that you could view all of it without needing an account :happy2:

I have been adding more projects and results to the gallery in the comments section over the last week ... Be sure to go check out the new stuff :D

I just saw the 2 videos. Dude jumping out the car had me cracking up! You have a nice following on Facebook. You can't pay me to sign up for any social media tho'.