forward firing vs down firing?

mrbofus

Howdy,
Is there a difference in the sound of a forward firing sub and a down firing sub? Isnt bass non-directional?
Sorry if this has been explained before.
Cheers
Greg

treitz3

Hello Greg. Done correctly, bass should be non-directional. That said, 95% [maybe more] of the systems I have heard, you could locate where the sub is which honestly leads me to believe that bass is directional in most cases.

The differences between the two I would consider a matter of personal preference. I personally prefer the sound of a front firing woofer more than a down firing woofer, mainly because they seem easier [to me] to integrate seamlessly into the room. They also tend to have a more accurate sound stage presence with the various rigs I have had over the years. In addition, they also tend to have less boom or exaggeration of certain frequencies but that really depends on a lot of other factors as well.

The sub I have now has both. Two active FF woofers and a passive DF woofer. When combined with the right amp and the Velo SMS-1, the integration becomes seamless and you can not tell where the sub is, let alone tell that there is a sub running.

Does that help you?

everpress

Not sure if anyone here appreciates Dr. Hsu for his studies in subwoofers or not... but here is an older article that states his opinion on the front/side firing vs. down-firing subs...

http://www.goodsound.com/features/2001_08_01.htm

From some of the guys on here, I've heard that the only reason to choose a preference is based on the number of children/pets your sub will be exposed to...

Knucklehead

I do know a down firing sub sounds like crap on carpet.....at least on my carpet.

grimmace19

^ Exactly right from my stance. I like having the down-firing to prevent my dog from throwing his ball/bone through it.

treitz3

Knucklehead wrote: »

I do know a down firing sub sounds like crap on carpet.....at least on my carpet.

Another thing to bounce off of your comment.....I have learned that when a DF sub is on a concrete slab or solid surface, regardless of whether there is carpet or not, the sound is tight when placed correctly. On the other hand, when you place that same sub on a suspended floor [second story, for example], the reverb from the floor or crawl space beneath can cause a rather unpleasant sound and added "boom" that I can't stand.

concealer404

treitz3 wrote: »

Hello Greg. Done correctly, bass should be non-directional. That said, 95% [maybe more] of the systems I have heard, you could locate where the sub is which honestly leads me to believe that bass is directional in most cases.

Sounds like a placement or room issue to me... or maybe i'm special. I've been special before.

The last subs that i've had in my setup both disappeared completely. The most notable being a Klipsch RW-10D, and mmadden28 had the same sentiments about that sub in his ML Depth/RW-10D shootout, that it completely disappeared.

But i'm sure that some subs just won't, no matter what. I could never get my Omni S10 to disappear, but i could get the S8 to disappear. Subs confuse me.

Knucklehead

treitz3 wrote: »

Another thing to bounce off of your comment.....I have learned that when a DF sub is on a concrete slab or solid surface, regardless of whether there is carpet or not, the sound is tight when placed correctly. On the other hand, when you place that same sub on a suspended floor [second story, for example], the reverb from the floor or crawl space beneath can cause a rather unpleasant sound and added "boom" that I can't stand.

Exactly, that may be what I experienced as I live on a crawl space.

grimmace19

I wish my subs would disappear because then my neighbors wouldn't know where its coming from

concealer404

grimmace19 wrote: »

I wish my subs would disappear because then my neighbors wouldn't know where its coming from

Buy an invisibility cloak, or just beat up Harry Potter for his.

Knucklehead

Maybe one of you college edumacated guys can develop some type of "cloaking" device.:p

mrbofus

treitz3 wrote: »

Hello Greg. Done correctly, bass should be non-directional. That said, 95% [maybe more] of the systems I have heard, you could locate where the sub is which honestly leads me to believe that bass is directional in most cases.

The differences between the two I would consider a matter of personal preference. I personally prefer the sound of a front firing woofer more than a down firing woofer, mainly because they seem easier [to me] to integrate seamlessly into the room. They also tend to have a more accurate sound stage presence with the various rigs I have had over the years. In addition, they also tend to have less boom or exaggeration of certain frequencies but that really depends on a lot of other factors as well.

The sub I have now has both. Two active FF woofers and a passive DF woofer. When combined with the right amp and the Velo SMS-1, the integration becomes seamless and you can not tell where the sub is, let alone tell that there is a sub running.

Does that help you?

Thank for the explaination, I have carpet and my future sub will be locates in a corner. Would a front port sub be best?
Greg

concealer404

mrbofus wrote: »

Thank for the explaination, I have carpet and my future sub will be locates in a corner. Would a front port sub be best?
Greg

Front firing would probaby be my pick there... The port is something a bit different, though.

treitz3

Yeah, ported -vs- sealed is a whole'nuther ball of wax to deal with. Apples and oranges type of thing, you know?

Erik Tracy

I am not a sound engineer, nor do I play one on tv, but with a down firing sub, wouldn't half (or more) of the radiated energy (since it is circular) be directed 'backwards' towards the wall behind where the sub is placed?

Wouldn't this result in less bass energy being radiated into the listening area and also created 'rear wall reflections'?

Maybe this is why sealed subs are 'better' for music? Just speculating - not poking anyone in the eye.... :)

grimmace19

concealer404 wrote: »

Buy an invisibility cloak, or just beat up Harry Potter for his.

What an amazing quote considering the **** upstairs is nicknamed harry potter because of his harry potterish appearance.

mrbofus

concealer404 wrote: »

Front firing would probaby be my pick there... The port is something a bit different, though.

Sorry, i meant front firing not front "port".
thanks for the input

dabo

everpress wrote: »

Not sure if anyone here appreciates Dr. Hsu for his studies in subwoofers or not... but here is an older article that states his opinion on the front/side firing vs. down-firing subs...

http://www.goodsound.com/features/2001_08_01.htm

good read, thanks

gp4jesus

to Knucklehead and concealer404: Can you guy help me? I'm trying to find a thread from 3-4-5 days ago. There I saw your replys to a guy w/a pair of RTi A5s trying to decide about bi-wiring & wire gage.

the thread got pretty long w/a bunch of people firing all kinds of stuff back and forth, some of it had almost nothing to do w/his questions.

mrbofus

everpress wrote: »

Not sure if anyone here appreciates Dr. Hsu for his studies in subwoofers or not... but here is an older article that states his opinion on the front/side firing vs. down-firing subs...

http://www.goodsound.com/features/2001_08_01.htm

From some of the guys on here, I've heard that the only reason to choose a preference is based on the number of children/pets your sub will be exposed to...

interesting article, Thanks.

gp4jesus

DF: A desirabel trait is 'upper registers' radiates to the sides and rears in effect a subtle accoustic filter. As others have mentioned, the lower/lowest registers FF or DF would have the same level

spnplgr

mrbofus wrote: »

Howdy,
Is there a difference in the sound of a forward firing sub and a down firing sub? Isnt bass non-directional?
Sorry if this has been explained before.
Cheers
Greg

I just got the SVS PC12-NSD cylinder down firing sub a few weeks ago. I have 20 X 13 theatre room with openings on one end to dining/kitchen area. I have all hardwood floors. My theatre and speakers are set up on the long side of room due to huge fireplace on the end. Total cu ft about 3500. I have not had another theatre system or sub, so I can only tell you of my experience with this sub. Been watching mainly movies like (Star Wars, Austrailia, 3:10 to Yuma, Spiderman, Pearl Harbor, Entrapment, Saving Private Ryan and a couple others). 90 % BluRay. With my setup, the bass is outstanding. The bass encompasses the entire sound stage. No direction at all. The subwoofer is disappeared. I have no experience with front firing, but I am totally satisfied and happy with my SVS down firing sub. Spend more than you can afford. You'll be glad you did.

Uilleann

As a very general rule, I believe you'll hear a more accurate tonal quality from a front firing sub, assuming it's also plced in the front of your listening environment - like your mains and center would normally be. There is a good amount of detail that radiates from a speaker's center, and that detail will change as you move towards the outer edge of the driver cone. This is particularly noticeable in igher frequency drivers as well, but holds true to a degree with bass drivers as well. With a downward firing, or ported (bass-reflex) design, you may loose some of the detail otherwise present when facing the driver directly. Bear n mind that cabinet design, sub placement, room size, furniture and listening position will all have some effect on the detail of your bass frequency response.

As best I understand it, the optimal placement for a bass driver, is in the same cabinet as your mains. This allows both a time coupled signal, meaning all frequencies will arrive at your ear at the same time - without the need for electronic time balancing for example, and assuming the speaker deigners have done their due dilligence, will also allow for a balanced and flat frequency response across the audible spectrum. Front firing enclosures can sometimes also enhance the feeling of tight 'punchy' bass frequencies when positioned in front, or nearly so, of the listener. A downward firing enclosure, particulary on carpet, may tend to dull or muddy the tone slightly. However, this is highly subjective and one listener's boom, may sound very tight and clear to the next.

When you take the sub out of the main cabinet(s) and move it into it's own enclosure, you add a whole extra dimension of complexity in achieving balance in tone, volume, and time delay issues. Many (probably most) current AV receivers today will have fairly capable processers to make this process simple, and should give you good results with either a front or downward firing enclosure. If you're able, I suggest taking some reference material you're very familliar with to your local electronics supplier, and demoing several different subs side by side if you can. Also, if possible, try to recreate the surface the sub will be playing on. Bear in mnd however, that the electronics showroom floor very rarely will be even a remote approximation to your own personal listening environment. But it may give you a but more of a feel of what you're after. Best of luck!

Brian~

comfortablycurt

As a general statement, yes, bass is non-directional. This is really only true in ideal(or very good) acoustic environments. In a purpose built room, with proper treatment, subs should completely disappear and be completely non-directional.

Most of us have far from perfect acoustic environments though, so properly integrating subs can be a little more involving.


I've found that different style subs work better in different situations. Down-firing subs radiate more uni-directionally, and tend to have a little bit more of the boom and thump that HT requires.

As far as musicality goes, I prefer front firing subs. They just seem to be a lot more accurate for more complex musical sequences. They tend to be tighter and more focused sounding in my experience.

I'm considering trying a couple Polk MicroPro2000's in my 2 channel rig sometime down the line. They combine forward firing woofers, with down-firing passive radiators, and are a pleasant mix of both worlds.

TNRabbit

The only decent down-firing sub I've ever heard was the VMPS Larger sub. However, it STILL had a front-firing passive radiator....

treitz3

TNRabbit wrote: »

The only decent down-firing sub I've ever heard was the VMPS Larger sub. However, it STILL had a front-firing passive radiator....

Make that two front firing woofers. One 12" and one 15". Both are active. The down firing woofer is a 15" passive.

kcoc321

MiisTran2010 wrote: »

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online debt management

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he-she must be really hard up....

TNRabbit

treitz3 wrote: »

Make that two front firing woofers. One 12" and one 15". Both are active. The down firing woofer is a 15" passive.

Then I HAVEN'T yet heard a decent down-firing sub...

Thanks, Tom~

jimed1

I got a free PSW125 with a recent speaker purchase. As many of you know, it is front firing, but ported on the bottom. I had a guy who used to own a hi-end audio store tell me that for carpeted floors, you should always sit the sub on something solid if the sub is downfiring (like plywood or something). So, I went out and bought an 18" x 18" piece of tile and put the PSW125 on it. I think it helped quite a bit. Seems like it took some of the "boominess" out. I probably won't keep the sub, since I have my eye on a micropro3000, but it's not too bad for movies. Anyway, have any of you guys tried this with a down firing sub?

concealer404

TNRabbit wrote: »

Then I HAVEN'T yet heard a decent down-firing sub...

Thanks, Tom~

http://www.audioc.com/speakers1/titanxl/titanxldetail.htm

TNRabbit

concealer404 wrote: »

http://www.audioc.com/speakers1/titanxl/titanxldetail.htm

I didn't say there weren't any, just that I hadn't yet heard one...