Do I need x1 sub?

I have a small system that I am making; so far I have for midrange 4 cabinets with 2 12inch speakers in each 400rms per cab in the old dual fane design and then a horn on top of each cabinet for the highs. So far so good for me.

Bass wise I want to make a horn with 15inch fane driver design is off of

William Cowan’s DIY home page The Horn Sub Jr This is a 40hz bass horn

I will use just 2 off these 1 each side    nice small size

Would the system be improved if I add to it?

 X1 with void 18 1000rms driver

I have an active crossover and 31 band EQ all digital and running on 3 amps

I could get hold of a Europower EP2500 to power 2 x1s

Not the best but might work

I guess the

X1 would cross at

65khz

Horn Jr

65 to 200hz

This part is already very good for me

Dual 12s Mid

200 to3.5khz

High horns

3.5 to 18khz

Thanks for any advice I am a novice that’s having fun.

Hi Paul

One thing to note- that guy makes his design look extra great by including the Corner loading bonus TWICE!(models in 0.5pi + has a corner extension on the input window)

Bill Fitz,Djk and the rest on AA agree.

You could get an efficient 65hz-200hz horn designed for your 15" if you have t/s specs for it-that way its not TOO BIG.the HD15 is like this if you build a couple.

Note that i dont know about using BP6+horn for kicks practically,so im assuming its a good idea.

Cheers!

G'day Philip and Mike

I guess I'd better jump in here to dispel some rumours. If you have a look at the following three images, you will be able to compare the model for the hornsubJr as I modelled it, and without the room influence (still 1/4 space), and compare the models with the actual measured response at my listening position. You will probably come to the same conclusion I did and agree that my published model more accurately reflects the measurement. LF extension is actually better than predicted. BTW the black trace is the raw response, the other trace has been tweaked in the DCX2496 crossover with a few stages of parametric eq.

http://diy.cowanaudio.com/images/hornsubjr_response.GIF - http://diy.cowanaudio.com/images/hornsubjr_response.GIF

http://diy.cowanaudio.com/images/Jr_nocnr.gif - http://diy.cowanaudio.com/images/Jr_nocnr.gif

http://diy.cowanaudio.com/images/Jr_cnr.gif - http://diy.cowanaudio.com/images/Jr_cnr.gif

Philip, back to your question, this little sub would be worse than useless in a 1/2 space environment, when used on it's own. 4 or more cabs and you will start to get useful response. I mentioned this on my webpage to make sure no one would waste their time making just one pair.

Cheers

William Cowan

Hi cowanaudio - i didnt mean to be aggressive etc-just stating what i thought to be true.

Certainly the measurement seems to agree more with the 2 corner modeling-but its too hard to say-it could be the result of slight room gain or modes.

But my point still stands,that it wont be true for all situations-

And youl still require several units to acheive desired response in 1/2pi

Cheers!

G'day Mike

>And youl still require several units to acheive desired response in 1/2pi

I don't doubt that for one minute, I even mentioned the fact on my webpage. I doubt it would ever be flat to 36Hz, 1/2 space, with any reasonable number of boxes. It is a 40Hz, small mouth bass horn, but in my room it behaves the way I'd expect a 30Hz horn to behave.

I guess you understand that a domestic listening room is far more constrained than a 1/4 space environment? I just tryed to reflect that fact in my model. This sub was not designed for pro sound, it is a domestic bass horn, and as such works better than I could have imagined.

BTW I don't ever recall seeing a model of any of Bill F's horns? The extreme small mouths and claimed low extension of his bass horns suggests to me he is using similar reasoning. Did you try to model one?

Cheers

William Cowan

Hi william

Well yes the domestic situation can well be less than 0.5pi- but how much we dont know- and walls vibrating and the lower bass passing through walls and not being contained within thin walls negates this -again we dont know how much,so id prefer to be slightly over specd than under.

Nope Bill fitzs horns are different and i havent bothered modeling one. I dont doubt his horn knowledge,Perhaps i disagree with his HT intention for some peoples uses-but for guitar type it seems quite useful

Btw the 2226 is still 'music to my ears

No plans of a super Ceiling-space basshorn with 18LW1400?

Cheers! 

It depends entirely on what the horn is like-id be interested to hear details on this.

They are robust drivers-its only some drivers that cant take moderate horn loading thesedays.

Cheers!

It's the Föön E920HL. 2 18LW1400 in a box of 119,5cm height, 50cm width and 79,5cm depth. Hornloaded as said, horn path is 1,65m, but I can't tell throat size, mouth size or flare rate. I know from guys who are using much of them that the speakers start to make problems after some time....

Interesting story: Föön now got a subbass horn very similar to the LAB sub. It even utilises the same speakers..... but has a slightly shorter horn.