Ultra compact ported 15" Dayton Ref HO

[turbodawg]

Here's another thread I got ideas from, the BMS driver used is actually pretty compareable in sensitivity to the 15" HO dayton in the models, if I recall correctly, however the 12" ho was 2-3 db less sensitive. The slight rise to 40hz is part of the design strategy, to get better output from a small box.

Q12 12" Sub - Speakerplans.com Forums - Page 1

[turbodawg]

Well I bought the mains for the system, Peavey Impulse 100, at a good price. Decent quality, sound, size, weight, and resale value. 96 db/w/m sensitive on the spec sheet, should get loud enough off 75w battery powered and I have a nice 200w per channel adcom to drive them for AC use.

I calc 117.7 db nominal with 2 speakers @ 1m 75w. The 15" HO sims at 118 db from 400w in winisd, 39hz f3. For AC use the adcom drives the pair of mains to 122db nom, and a pair of subs 800w each with one plugged port (~26.5 hz tune) hits 120 db nom with a 29hz f3 (add room gain as applicable, and ports can be unplugged for more gain as needed). Am I on the right track here?

Time to get serious about a sub or two.

[turbodawg]

Originally Posted by turbodawg

Here's another thread I got ideas from, the BMS driver used is actually pretty compareable in sensitivity to the 15" HO dayton in the models, if I recall correctly, however the 12" ho was 2-3 db less sensitive. The slight rise to 40hz is part of the design strategy, to get better output from a small box.

Q12 12" Sub - Speakerplans.com Forums - Page 1

Actually, in my horn resp models the bms did about 92 db on 2.83v, and the 15 HO 95 db on 2v, with similar response plots. Even if dayton is fudging the numbers, that's a big margin for error.

[m R g S r]

Originally Posted by turbodawg

800w each with one plugged port (~26.5 hz tune) hits 120 db nom

Without chuffing / noise?? That's full power into that driver (x-max plus) id be weary of driving it to full power without noise...

[m R g S r]

Originally Posted by turbodawg

I calc 117.7 db nominal with 2 speakers @ 1m 75w. The 15" HO sims at 118 db from 400w in winisd, 39hz f3. For AC use the adcom drives the pair of mains to 122db nom, and a pair of subs 800w each with one plugged port (~26.5 hz tune) hits 120 db nom with a 29hz f3 (add room gain as applicable, and ports can be unplugged for more gain as needed). Am I on the right track here?

Time to get serious about a sub or two.

well remember that our ears are much less sensitive to LF.... I'm betting those tops will out shine the single sub or two if not horn loaded or in a proper sized box for PA....

[turbodawg]

Originally Posted by m R g S r

Without chuffing / noise?? That's full power into that driver (x-max plus) id be weary of driving it to full power without noise...

I'm pretty sure a 5" round port should be fine. It's under 100 ft/sec in winsid with 800, and under xmax. We're only talking about a ~30hz f3, people get these down to 20hz all the time. The small box is a factor.

[m R g S r]

Btw if you want to come down one weekend to test the cabinet outdoors that I have built with the Dayton Ref HO 15 feel free...I have plenty of amp power available
this is copied from my install thread on diyma...

Originally Posted by m R g S r

Got started (and finished actually) on the subwoofer enclosure...turned out to be 2.0 cubic feet internal volume after subtracting the subwoofer displacement and the port duct displacement....tuned to roughly 27hz....
made it from 1/2" Baltic Birch plywood


all buttoned up!


i wasn't going to finish the box, but had some extra neffy wrap lying around and some extra 3M spray 90 so i figured what the heck

I know it would be easier to measure for you, except I have no measurement equip

[turbodawg]

Originally Posted by m R g S r

well remember that our ears are much less sensitive to LF.... I'm betting those tops will out shine the single sub or two if not horn loaded or in a proper sized box for PA....

Not much I can do about it, these are the biggest boxes I can fit, and they are about as efficient as any other BR box I could come up with.

[turbodawg]

Originally Posted by m R g S r

Btw if you want to come down one weekend to test the cabinet outdoors that I have built with the Dayton Ref HO 15 feel free...I have plenty of amp power available
this is copied from my install thread on diyma...

I know it would be easier to measure for you, except I have no measurement equip

That's a good idea, when I get the mains, I'll rig up an outdoor test with my old ava15 to see if it can keep up, should be fairly compareable. Thanks!

[turbodawg]

So I've started to flesh out a box design, no plans yet but here's what I'm thinking.

- 22x19x16 inches external.
- Woofer on the 22x16 face
- 16x16 baffle offset to side, recessed 1.5" inwards
- 1/4" wood on baffle out to perimeter of box, 1/2" wood inside that to support grille
- 2 x 5" x 24" ports on same face, outside grille/woofer baffle
- PVC drain pipe ports with long 90 degree
- No port flares, for simplicity
- Thin aluminum strapping to hold ports in place
- Slat bracing as needed on panels
- 1/2" birch plywood
- Internally coated with rubber roofing mastic
- no filling
- thin, large area rubber feet
- pole mount for main speaker on side
- intended to be placed on it's side
- target weight under 60 lb w/driver

Your thoughts?

Also looking at pro sub amps, what do you think about the QSC GX5 at 700w 4 ohms vs. GX7 at 1000w 4ohms? It's nominally a 1.5 db difference for a $200 price jump.......