Make a Comment on my 15inch sub

[OMNIFEX]

Re: screenshots.

omni-
i think we must agree on most things..


i think we both admit

--that the 15inch700 does not give quite the optimum response without eq.

..but with no other choice! its good enough.Not ideal,but ok.

because it is 97db i can afford 3db of Eq.


if i was wanting true(normalised as u say) -3db at 34hz a shiva would do it better BUT it happens to be 10db less efficient and does more 20hz bass ofcourse but cant match the effiency in the midbass.

Ah.

The good 'ole Low Bass -vs- Efficiency dilema.We all experience
this at one point or another.

Thanks for the help! I hope this works .....................

 

[OMNIFEX]

Re: Horns

Hey Omni!

I love horns too I'm currently designing my new pair of main speakers based on horns, and will most likely use JBL 2370A horns with P.Audio SD-450N compression drivers (800Hz-20KHz) with compensation of course, I will be building two midrange tractrix horns which will load 8" Eighteen Sound 8M400 driver 200Hz-800Hz, and for the midbass (70Hz-200Hz) probably JBL 2226H or a 15LW1401. The Eighteen Sound 8M400 seems a very good candidate for horn loading, and Hornresp predicts very good results also. If you have any other suggestions on drivers for midrange tractrix horns, I would like to know!

Adrian

The crazy thing is, if I never understood how horns
work (To an extent) with speakers..........

I'm no expert on horns. I do know that the JBL 2227H is
a better candidate than the 2226H for a horn loading

2226 H = EBP 121, QTS 0.31, no: 3.283%

2227 H = EBP 182, QTS 0.21, no: 4.924%

check out these sites;

www.beyma.com
www.precision-devices.com
www.bcspeakers.com
www.mccauley.com

They all offer horn designated drivers.

Just to keep your options open.

Best Regards,

 

[mikee12345]

yep i see the graph.


yep and at the moment efficiency wins.>im studyinbg the labhorn at the moment

later with more money perhaps more lower frequency stuff eg lab or peerlesss or shiva...but thats later when im not a poor student


the eminence box program looks ok.

i wouldve tuned the peerless lower since thats where its meant to be used :-D personal preference though.

<25hz

http://cowanaudio.com

 

[OMNIFEX]

How did you know I tuned it at 21Hz????


Efficiency is my goal also. One of the reasons why I prefer
using dual drivers oppose single.


Take Care.

 

[mikee12345]

i would liek to kno what box size and tunings for each of those...




i like efficiency too.so i use 1 efficient driver rather than 2 inefficient ones

Fs=38hz Q=0.3,Vas217litre,98db/1watt,15inch.

that one is quite flat.
tune to 32hz and boost 4db :-D

 

[OMNIFEX]

mikee12345,

I never saved the design. I do remember that they were
in 200 liter (EXACT) cabinets dual drivers. (100 liter a
driver) Both tuned to 21, and, some change hertz.

I don't remember what was the efficiency rating in dB's
However, I can run the numbers again if you like.

Remember that was the Normalized Gain Chart. Expect
a lower response (-3dB) once you use the 1 watt or
2.83 volt method when using dual drivers in one box.
I generally use 2.83 volt for dual drivers

Best Regards,

 

[mikee12345]

heres my slightly different 15inch from same manufacturer

Fs=38hz
Q=0.3
Vas=217
Xcursion=8mm (xmech 29mm)
98db/1watt

this speaker goes fine in 160litres Fb=32hz
32hz 4Db EQ. il use this instead i think :-D

tuning below speaker resonance isnt a problem with these speakers,and if it is,then macky888, u owe me ur 18inch ;-)

 

[OMNIFEX]

Oh Yeah!

I like this driver better than the previous 15 you were
going to use.


Go For It

 

[macky888]

I like it too, I was actually the one that suggested it to him, for a number of reasons:

1. It offers the same level of performance in a smaller box, with the same Fb
2. It does not require parametric equilization, a simple 2nd order sallen and key type EQ filter works fine here
3. Less EQ needed and hence;
4. Higher System power handling
5. The driver has much higher excursion (damage limited excursion is actually 35mm and not 28mm as mike incorrectly posted, the 15MB700 only has 23mm).
6. The 15W700 cosmetically looks nice, whereas the other 15MB700 looks like a dorky piece of sh*t!

Adrian

 

[OMNIFEX]

You know how you can tell this speaker beats it,
without getting into specifics?


15 Mid Bass 700

15 Woofer 700

This is why I was against the 15MB700 all along!

The model number told me it wasn't
designed for the job.


Best Regards,

 

[macky888]

That is true, but the 15MB700 could still have been used. The 15W700 seems better suited to his application though. I originally told him about the 15MB700 as he asked for a 15" driver from Eighteen Sound that had the lowest Fs (fs on the MB700 is 34Hz, on the W700 is 38Hz). The 18Sound catalogue did not have any lower than the MB700.

And hey! My posts come up straight away now! YAHOO!!!!!!

Adrian