How hard is it to design a speaker with side-firing woofers?

a4eaudio

I am going to have modular bass-bins with dual 12" woofers each, crossed over likely around 350Hz. Front-firing I'm probably looking at approx. 14" wide baffle. I can do that if I have to, but it sure would be nice to go dual-opposed side-firing and keep it narrower.

I did a little research and at diyaudio most of the opinions were that you can't go much above 200Hz because of the localized frequencies above that. But I don't put a lot of stock in some of the posts over there. Although it does intuitivly makes some sense I can find well-received designs that do go higher.

I have a good measurement setup and can take 0-180 degree measurements far off the ground. But if it is possible, but very challenging, I'll probably just pass and take the road more travelled.

Steve_Lee

IME side firing 12" woofers are fine as long as you treat them as subwoofers with an XO of 150 Hz and lower as you will miss the punch and tactile feel/sound of the midbass coming from them if crossed higher.

Just my $0.02

Wolf

FWIW, those opinions are pretty accurate. About 200Hz is the limit. John did this with a little 3way using the DCS165, and was not happy with the blend and how high he took the woofer.

rjj45

@Steve_Lee said:
IME side firing 12" woofers are fine as long as you treat them as subwoofers with an XO of 150 Hz and lower as you will miss the punch and tactile feel/sound of the midbass coming from them if crossed higher.

Just my $0.02

Thanks buddy - I was considering a side firing woofer in my new build, but a good punch is essential for this.

ugly_woofer

@a4eaudio said:

I have a good measurement setup and can take 0-180 degree measurements far off the ground. But if it is possible, but very challenging, I'll probably just pass and take the road more travelled.

David, taking the measurements off the ground might give you a pretty graph, but I believe you are better off taking the measurements at whatever height the speaker will be used, and this is where there will be disagreement, but if you take it at the operational height, you'll get the floor reflections that you will encounter while using the speaker, so why not see/deal with them while designing and not some idealized graph of an elevated speaker.

jhollander

Like Ben said I did not like side firing woofers. With my Latus design I had to cross the side firing woofers at 250 Hz. With LR4s there still a bunch of directional content. If I did this again I'd push for under 200 Hz, and steep crossover slopes.

You could do a bandpass bass bin to keep the front narrow.

a4eaudio

@ugly_woofer said:
David, taking the measurements off the ground might give you a pretty graph, but I believe you are better off taking the measurements at whatever height the speaker will be used, and this is where there will be disagreement, but if you take it at the operational height, you'll get the floor reflections that you will encounter while using the speaker, so why not see/deal with them while designing and not some idealized graph of an elevated speaker.

Thanks, I had wondered about that.
I think I'm just going to skip the side-firing idea for this one. I'm hoping to build the bass-bin with the flexibility to be adaptable with multiple two-way "tops". I think that would require a lot of extra measuring a tweaking every time if they were side-firing.

PWRRYD

I like the wider bass bin idea with narrower two way tops. I did that several times and it can work quite well. Plus they're easier to move around.

jr@mac

NHT crossed their side firing 8" in the ST4 at 135hz. I forget what they crossed the 12" big boy at, but I'm guessing somewhere south of there.

One thing you will have to worry about is getting voicing correct. You will get considerable reinforcement from the proximity of the woofer to the floor. If you are within a few feet of any other boundary, it will be even more.

I don't personally think the headache is worth it, but YMMV.