Isobaric - less then $20

[revboden]

I vote for: Tapped Reverse-Tapered Quarter-Wave Voigt Pipe, or T-RTQWVP for short-hand.

 

[HOPHANTHIET]

ISOBARIC

9.0oz....right on the dot.

HAPPY NEW YEAR ,

JUST READ THE POST, PAGE 1 TO 15;WANT TO BUILD A SET FOR MYSELF.

 

[NEO Dan]

In Carlson's defense, a man ahead of his time aparrently. The unlucky fellow was born before Hornresp.

 

[harmolodics]

plate amp option

does the box need to be altered at all to accommodate a small plate amp? (like the Dayton SA25 mentioned earlier) would it obstruct the line if it were just installed in the current design?

 

[revboden]

harmolodics,

Yes, it would mess with the line. I'd just build a little box to the back of the existing design. (with top and bottom vents)

edit: that said, I don't like speaker mounted amps, too much vibration. Amps don't like vibration.

 

[Josephjcole]

Nice work guys! They do seem like the might be a good ticket for someone wanting to build multiple subs on a budget. I looked but didn't see any print outs from horn response... NEO Dan is there any chance we could see the horn response predictions? Predicted sensitivity, predicted reponse, power handling, etc?

curious minds want to know...

 

[revboden]

Hi Josephjcole,

check post 105: http://www.diyaudio.com/forums/subwoofers/203345-isobaric-less-then-20-a-11.html#post2853987

 

[NEO Dan]

Hi Josephjcole,

check post 105: http://www.diyaudio.com/forums/subwoofers/203345-isobaric-less-then-20-a-4.html#post2853987

Fixed

 

[ODougbo]

double trouble box

Nice work guys! They do seem like the might be a good ticket for someone wanting to build multiple subs on a budget. I looked but didn't see any print outs from horn response... NEO Dan is there any chance we could see the horn response predictions? Predicted sensitivity, predicted reponse, power handling, etc?

curious minds want to know...

They work nicely, I took a pair up to the HT last night, listened to several action movies, etc. I'm giving them the thumbs up.

The 8ohm is nice, I don't really like using 4ohm loads (if I don't have to).

I did use 18mm on the outside on #3 (6 sides), the inside 1/2", I added to the length so the inside stays the same.

I read that there is no such thing as bass "speed", but the bass here seems lighting fast (to me).

Making a double trouble box now....Can't wait to see that acronym.

 

[2009thread1]

i found these woofers on ebay, from america for about 8.99 and 16.99 p&p, but is it worth the price and how would it compare to a single 8" ? or even the existing tapped horn ive got with two 6.5" woofers ?

 

[ODougbo]

Hard to say what you are used to, not much $$ in any case.

The best deal is to order 4, maybe make a double box (I'm pretty sure this can be done with one sheet).

Here is a pic, if I had to do this all over again, it would be a little bit neater job, but this should turn out okay.......

 

[2009thread1]

whats the overall size of the box ? i could build two

 

[Josephjcole]

Hi Josephjcole,

check post 105: http://www.diyaudio.com/forums/subwoofers/203345-isobaric-less-then-20-a-11.html#post2853987

hmm... well that's embarrassing... missed that post some how... thanks for the link!

 

[Josephjcole]

whats the overall size of the box ? i could build two

http://www.diyaudio.com/forums/subwoofers/203345-isobaric-less-then-20-a-5.html#post2847381

 

[ODougbo]

The 2 for 1 box is going well.

Cost - 4 speakers $32. 1 sheet 1/2" mdf $25.
(may need extra small piece mdf, not sure)

 

[2009thread1]

this design seems to be smaller then the tapped horn ive got, im going to have to have a good think about these

 

[ODougbo]

This is 17-1/2" wide, (sharing one side).

 

[NEO Dan]

this design seems to be smaller then the tapped horn ive got, im going to have to have a good think about these

Does 009 have a name?
The JBL 8" is good but 2 in one box is the way to go.

This is 17-1/2" wide, (sharing one side).

KraZy man, how are you going to handle the outer pannels - lap joints?

Your 8" will work too BTW.

 

[ODougbo]

I cut the top of one (easy to do), and put on a full piece ~ going to ship lap the bottom (router cut).

The RFFG will work? oh no.......YIKES! I'm walking and talking in circles now.

btw, The P2 is a nice little woofer

 

[NEO Dan]

Neither of the 8" drivers is as efficient, but they have more x-max so they can get louder.
I am working on a source for a cheeep 10" shallow mount woofer that is suited to T-TQWT designs that go into the mid 20Hz range. No Free Lunch though = Bigger box = Bigger BASS. But still cheap