What to build with these...

[Mayday]

I'm going to use these Philips AD 706 6,5" Fullrange elements, quite modified.
Measured data:
8 ohms
Q=0.7
Vas= 17 liter (0,6cu.ft)
Sensitivity = 90dB
Fs = 70Hz
supposed to roll off at 18khz







They are dusty and dirty but in perfekt shape.

I'm leaning towards horns or dipoles, what du you guys think?

[Zen Mod]

depending of room and space you have;
try them on temp baffles ,then- if you think they deserve that,build bigger baffles with 15" bass helper and helper tweet ( if needed) ;

look at "beyond the ariel " thread

and- google for "lampizator" , then check his speaker pages

if you have no room for OB, find this :

http://www.sonido.hu/adat_pdf/DIY/DIY-MH-14-light3.pdf

[Mayday]

Originally posted by Zen Mod
depending of room and space you have;
try them on temp baffles ,then- if you think they deserve that,build bigger baffles with 15" bass helper and helper tweet ( if needed) ;

look at "beyond the ariel " thread

and- google for "lampizator" , then check his speaker pages

The speakers I'm building are for my brothers daughter, it's her first stereo I'm putting together. For ampification I'll use LM3886 chipamp.
My brothers budget for this build doesn't allow for further drivers.

Do I understand you correct that you suggest open baffle design?

I use that myself with Dayton 15" IB, Seas P17RCY and B&G NEO8.

[Mayday]

That horn design you linked to looks intresting, do you think this driver is suitable for that?

[Zen Mod]

Originally posted by Mayday
That horn design you linked to looks intresting, do you think this driver is suitable for that?

even if not completely adequate - and you can find out only building it- it will be miles ahead any boxie box you can made for it.

all that - if that driver is anywhere near old good AD Philips series.

anyway-little girl will be thrilled with completely unique spks

now-serious- good horn construction are way more forgivable to various driver than closed or BR boxes.
at least for my limited knowledge

[Mayday]

These drivers are Philips AD 706 but modified.
Thanks for the advice that horn looks really intresting.

[Mayday]

After talking to the girl that is going to use these speakers, she was leaning towards OB design, since she likes my dipoles.

Question is, can these drivers alone on an OB reach adequate listening volume? Not Very loud, just enough for everyday use in an apartement.

[Geoff H]

Mayday, would you believe I am currently working on some 6" Panasonics, with a Fs of 76Hz, on little OBs. The idea was to extract as much sound from these as possible.

OK, they won't shake the floor, but do go quite low for what they are.

The size of the baffle is 460mm high, 300 wide, with sides, 165mm at the lower end, tapering to 118mm at the top, (to be reduced) and a full width top shelf of 76mm.

All made from recycled MDF. I started with just the baffle. Played with different sized wings, to bring the bass up. I have lost a bit of sound stage, that's why I am trimming down the sides. in my case, a bass helper will fix the bottom octave or two.

I would give the back of the cone 1 coat of PVA, the whizzer 1 coat, front and back, the area behind the whizzer a coat, then 1 more coat over all the front of the main cone.

If you have some bitumen paint/sealer, some around the perimeter of the whizzer kills of some edge resonance. A light coat on the roll surround will raise the Fs a bit, which is OK on the small baffle. Mine started at 70Hz.

She will be pleased. I have passed on a few tweaking experiments to younger folk.

Geoff.

Edit: Hey Zen, they are old Philips. Not old enough for alnico though.

[Mayday]

Originally posted by Geoff H
Mayday, would you believe I am currently working on some 6" Panasonics, with a Fs of 76Hz, on little OBs. The idea was to extract as much sound from these as possible.

OK, they won't shake the floor, but do go quite low for what they are.

The size of the baffle is 460mm high, 300 wide, with sides, 165mm at the lower end, tapering to 118mm at the top, (to be reduced) and a full width top shelf of 76mm.

All made from recycled MDF. I started with just the baffle. Played with different sized wings, to bring the bass up. I have lost a bit of sound stage, that's why I am trimming down the sides. in my case, a bass helper will fix the bottom octave or two.

I would give the back of the cone 1 coat of PVA, the whizzer 1 coat, front and back, the area behind the whizzer a coat, then 1 more coat over all the front of the main cone.

If you have some bitumen paint/sealer, some around the perimeter of the whizzer kills of some edge resonance. A light coat on the roll surround will raise the Fs a bit, which is OK on the small baffle. Mine started at 70Hz.

She will be pleased. I have passed on a few tweaking experiments to younger folk.

Geoff.

Edit: Hey Zen, they are old Philips. Not old enough for alnico though.

I'm thinking of a baffle size of about 1,5x1m or there around.
A few questions; what's PVA, and what's wizzer?

[Geoff H]

PVA = Poly Vinyl Acetate = white wood working glue. Others use Puzzlecoat and or Damar. Dave at Planet 10's a guru in that area.

Whizzer = the little cone or tweeter cone.

Baffle size. Bigger is better.