Folded horn sub for a Klipsch Heresy

My fault on the throat chamber front panel!

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Cool! I got nervous thinking IF 12PT comes back then might not be cheap - so bak-ordered "2" - they be like a comfort blanket - good spec - can move air if one has power - no stinkin' foam surround to rot. I have cheap new MCM foam surrund drivers from 5 years ago - surrounds totally gone - same with 6PEV13 Audax.. Vintage JBL foam - looked like "circus peanutx" candy - stiff - rotted. - KLH vintage speakers - still play with cloth surrounds - Henry Kloss was a speaker making god including cones.
 
$70 for an 18" driver is better than the $29 JBL 12" driver.

18PT-8 = 1,234cm2 Sd.
CX1200 or GX1200 = 551cms Sd.

1,234cm2 / 551cm2 = 2.24 12" drivers to match the 18" driver in cone area.
1,234cm2 / 531cm2 = 2.31 12" drivers to match the 18" driver in cone area.

12PT-8 = 530.9cm2 = Quantity: 1-3 $49.98/ea.
18PT-8 = 1,234cm2 = Quantity: 1-3 $69.90/ea.

3 x $49.98 = $149.94.
2 x $69.90 = $139.98.

No contest, 18PT-8 all the way!
 
True on the 18 - but my spot for a 4 foot tall sub is only about 15" wide at best nnd hen blocking over half of a DVD rack. I can't see well with my monitor - which of the designs that is not isobarik goes low enough to have some fun with 18PT?

Years back I ran 4-18" Eminence vented boxes - one pair 6.4CF (picture below) and slightly taller pair on the bottom at 8.2CF. They R-J- vented in style seen iin an early 1950's Radio and TV News magazine where the builder made hic cabinet of asbestos board and de-Q-ed the whole system with an array of holes going straight through the front panel- then through the baffle.


This was the top / 6.4CF vented box- it was cool to be able to poke a mic into the aperture and see the summed response - plus it played very nice with a 103g (IIRC) Eminence 18. The box below had mms ~130g Eminence with fs 23Hz. I still with I had gone with K18 just for kicks.
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yah - a 3-way PA sounds like a good idea for GRS 18PT. How about this nice $31 or so compression driver ?:

https://prvaudio.com/products/d270ph-s/

Do you know of cheap and cheerful horns for that mid-driver?

Partsexpress is selling great B52 horns thick ABS for $3.95 made to snug against a 15"

What might be bargain horn tweeter? (for high tweeters - I like ST200 JBL/Selenium)


This is a recipe for a cheap 18" version of a Heresy I - ha
 
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ha - those look "good" and "good enough" - Rockville's compression driver looks familiar - the whole design looks good - How do they fare for home listening ? I think I saw a review for RV's big amp at ASR. (I've got a cheap Crown 3000 ?) rated 1KW/channel into 8 - has a big toroid.
 
Great to me!

I went from 5.1.2 Dolby Atmos with the 8's and 7.1 with the 15's at the previous house to three 5.1 systems at the current house.

Basement work from home office:

15" center channel.
4 x 8" LR & rear surrounds.
18" Road Yamaha BR bin.

Basement chill spot:

3 x 15" LCR.
2 x 8" rear surrounds.
2 x 12" BP4 coffee table.

Living Room:

3 x 15" LCR.
2 x 8" rear surrounds.
15" T-TQWT (negative flare tapped horn).

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