D-Rex Posted July 26, 2004 Share Posted July 26, 2004 Which do you like and why? I don't have alot of experience with subwoofers but I really liked the front firing RSW15. My question pertains to how powerful are the down firing subs and can it feel like they are "firing" the shock waves at you? I am going to be building my own so I would like some opinions please. Give me some reasons for either... or both. Thanks, D-Rex Quote Link to comment Share on other sites More sharing options...
dantfmly Posted July 26, 2004 Share Posted July 26, 2004 I like a sub that has both. Mine has a down firing active and a front firing passive. and yes it makes it feel like the waves are coming at you. Quote Link to comment Share on other sites More sharing options...
gcoker Posted July 26, 2004 Share Posted July 26, 2004 Definitly front firing. With carpeting in the living room I do not want anything absorbing the impact of explosions. Quote Link to comment Share on other sites More sharing options...
Juba310 Posted July 26, 2004 Share Posted July 26, 2004 I doubt carpet would effect the performance very much at all, due to the long wavelength of bass waves. Quote Link to comment Share on other sites More sharing options...
cjgeraci Posted July 26, 2004 Share Posted July 26, 2004 Very interesting thread. I have owned both down firing and front firing subs, and even though I like the sound of both designs, I tend to like the front firing configuration a little better. To my ears, not as much overall force, but more accurate, tighter bass. I have run my SVS subs both ways (original down firing and front firing - with plates removed). For the time being, my PB2-ISD is going to remain in the front of my setup "front-firing," and the 20-39PCi lengthwise, behind the couch, now "side-firing" -so to speak. At one point, Tom at SVS said there was enough demand from PB2 owners (isd,+,ultra) who were running their subs front firing that SVS planned on making a grill for those who wanted to run their PB2s that way. Do not know if SVS ever got around to that - with all the new model introductions, new plant, etc. Until they do, I will just have to keep protecting the twin 12s from my toddler, etc. Carl. Quote Link to comment Share on other sites More sharing options...
formica Posted July 30, 2004 Share Posted July 30, 2004 Theoretically, if the centre of the woofer cone is placed in the exact same spot in either configuration, the sound will be identical whether front or bottom firing. The wavelengths are simply too long. The change of the cone centre itself will should make a very small difference, and it's effect will vary with your room. Psychologically, it's a very different matter... as a front firing driver will look/seem more powerful with ba wider frequency response while a downward firing one will seem less directional. Both these claims have no scientific backing. If you have young children or parties, downward firing can be safer in avoiding pushed in dust caps or other accidents. If you listening room is in a controlled environment, front firing looks more impressive. I built mine with a front firing driver, as it seemed more powerful and had a better frequency response Rob Quote Link to comment Share on other sites More sharing options...
CAS Posted July 30, 2004 Share Posted July 30, 2004 ---------------- On 7/26/2004 3:42:49 PM D-Rex wrote: Which do you like and why? I don't have alot of experience with subwoofers but I really liked the front firing RSW15. My question pertains to how powerful are the down firing subs and can it feel like they are "firing" the shock waves at you? I am going to be building my own so I would like some opinions please. Give me some reasons for either... or both. Thanks, D-Rex ---------------- Building your own it would probably be more cost effective and less complicated to build a front firing sub, however mine is downfiring and it is brutal. I think with a sub this powerful it is much more stable to point the drivers down to keep gravity a contributing force and hold the enclosure in one place while the cones go nuts. I've tried front firing and it does sound a tiny bit more precise, but I get much more non-directional and gut-wrenching bass when down firing. Awesome! ps. carpet can have a positive affect. Quote Link to comment Share on other sites More sharing options...
D-Rex Posted July 30, 2004 Author Share Posted July 30, 2004 ---------------- On 7/30/2004 1:07:07 AM formica wrote: Theoretically, if the centre of the woofer cone is placed in the exact same spot in either configuration, the sound will be identical whether front or bottom firing. The wavelengths are simply too long. The change of the cone centre itself will should make a very small difference, and it's effect will vary with your room. Psychologically, it's a very different matter... as a front firing driver will look/seem more powerful with ba wider frequency response while a downward firing one will seem less directional. Both these claims have no scientific backing. If you have young children or parties, downward firing can be safer in avoiding pushed in dust caps or other accidents. If you listening room is in a controlled environment, front firing looks more impressive. I built mine with a front firing driver, as it seemed more powerful and had a better frequency response Rob ---------------- You mean after all of the "in theory" speech your's seemed more powerful and had a better frequency reponse as a front firing sub? Funny... What driver did you use for your subwoofer? Quote Link to comment Share on other sites More sharing options...
D-Rex Posted July 30, 2004 Author Share Posted July 30, 2004 ---------------- On 7/30/2004 7:47:20 AM CAS wrote: Building your own it would probably be more cost effective and less complicated to build a front firing sub, however mine is downfiring and it is brutal. I think with a sub this powerful it is much more stable to point the drivers down to keep gravity a contributing force and hold the enclosure in one place while the cones go nuts. I've tried front firing and it does sound a tiny bit more precise, but I get much more non-directional and gut-wrenching bass when down firing. Awesome! ps. carpet can have a positive affect. ---------------- What kind of effect would a down firing sub have on a house with crawl space, in other words, not a concrete slab? Would that absorb more of the impact or would it be easier to shake the house down? Quote Link to comment Share on other sites More sharing options...
FlyingV Posted July 30, 2004 Share Posted July 30, 2004 What about Up-Firing? Raised floor is 2x6 construction Glued to floor with PL. Double layer OSB glued to the 2x6s. Chamber created using cross-brace for correct volume with screws every 1.5 inches. Extra glue for air-tight enclosure along with a couple internal vertical braces. Dual port tubes sized and cut for 35Hz tuning. Great for Theater use... Quote Link to comment Share on other sites More sharing options...
D-Rex Posted July 30, 2004 Author Share Posted July 30, 2004 ---------------- On 7/30/2004 10:54:16 AM FlyingV wrote: What about Up-Firing? Raised floor is 2x6 construction Glued to floor with PL. Double layer OSB glued to the 2x6s. Chamber created using cross-brace for correct volume with screws every 1.5 inches. Extra glue for air-tight enclosure along with a couple internal vertical braces. Dual port tubes sized and cut for 35Hz tuning. Great for Theater use... http://forums.klipsch.com/idealbb/files/labeled.JPG"> ---------------- Very interesting setup! I envision this being like a roller coaster ride! Quote Link to comment Share on other sites More sharing options...
yromj Posted July 30, 2004 Share Posted July 30, 2004 Put one of those slotted thingies like on a coin-op laundry machine and w/ the right "music" you could sell rides on your couch. John Quote Link to comment Share on other sites More sharing options...
yromj Posted July 30, 2004 Share Posted July 30, 2004 ---------------- On 7/26/2004 7:11:10 PM Juba310 wrote: I doubt carpet would effect the performance very much at all, due to the long wavelength of bass waves. ---------------- This is the case. John Quote Link to comment Share on other sites More sharing options...
CAS Posted July 30, 2004 Share Posted July 30, 2004 ---------------- On 7/30/2004 10:33:38 AM D-Rex wrote: ---------------- On 7/30/2004 7:47:20 AM CAS wrote: Building your own it would probably be more cost effective and less complicated to build a front firing sub, however mine is downfiring and it is brutal. I think with a sub this powerful it is much more stable to point the drivers down to keep gravity a contributing force and hold the enclosure in one place while the cones go nuts. I've tried front firing and it does sound a tiny bit more precise, but I get much more non-directional and gut-wrenching bass when down firing. Awesome! ps. carpet can have a positive affect. ---------------- What kind of effect would a down firing sub have on a house with crawl space, in other words, not a concrete slab? Would that absorb more of the impact or would it be easier to shake the house down? ---------------- You mean storage under your floor? That may well shake things up a bit. But this depends on a host of other factors, like placement, materials used and ability of your sub. I would think that corner loading your sub and assigning listening positions far between any sub-floor load bearing joists and walls would definitely create some up and down movement in your posterior. Where are you planning to put it? Quote Link to comment Share on other sites More sharing options...
D-MAN Posted July 30, 2004 Share Posted July 30, 2004 Down-firing cabinets use the "slot" for upper-frequency limiting. They are technically considered somewhat between a horn and a simple port (more or less). Front-firing versions, of course, do not limit the frequency other than the characteristics of the woofer and the crossover employed. The down-firing type may be slightly more efficient in the low-end for this reason, all things being equal. Less energy would be absorbed by a concrete slab than on a hollow structure which the crawl space underneath a floor would present. All non-air vibration is lost energy. DM Quote Link to comment Share on other sites More sharing options...
D-MAN Posted July 30, 2004 Share Posted July 30, 2004 I forgot to mention this all-important fact: the bottom firing version uses the floor and the cabinet to achieve a 1/4 space (2 angled surfaces) which is more efficient bass-wise than the free standing 1/2 space (1 angled surface being the floor) front-firing version. The efficiency of both would be increased if placed in a corner (1/8 space). I may have the terms messed up, but the concept is sound. DM Quote Link to comment Share on other sites More sharing options...
formica Posted July 30, 2004 Share Posted July 30, 2004 ---------------- On 7/30/2004 10:28:39 AM D-Rex wrote: You mean after all of the "in theory" speech your's seemed more powerful and had a better frequency reponse as a front firing sub? Funny... What driver did you use for your subwoofer? ---------------- My comment was sarcastic ... I designed it as front firing. I have no children, wild parties, and preferred the visual appearance of a front firing driver. Even moving the sub around slightly (inches) didn't produce significantly different in-room measurement. Given the long wave lengths involved (a 80Hz x-over tone is over 14feet long) it does not make much of a difference wether it is front (Klipsch Ultra THX), rear (Klipsch RSW), or bottom facing (Klipsch KSW). It's more of a pratical, visual, and marketing decision. BTW, I used the Stryke AV15 driver in a Klipsch Heritage inspired enclosure ---------------- On 7/30/2004 10:33:38 AM D-Rex wrote: What kind of effect would a down firing sub have on a house with crawl space, in other words, not a concrete slab? Would that absorb more of the impact or would it be easier to shake the house down? ---------------- A wood structure will resonate while a concrete one will be more reflective, each having it's own pros and cons. A wood structure's vibration will shake the sofa and your body more, often giving the impression of more bass. Because this resonance is structure controlled, it may or may-not produced some unwanted distortions. A concrete slab will reflect more of the sound into the room with less distortion, but you will have a lessened tactile feel. You will be given the impression of a reduced bass response. ---------------- On 7/30/2004 3:43:52 PM D-MAN wrote: Down-firing cabinets use the "slot" for upper-frequency limiting. They are technically considered somewhat between a horn and a simple port (more or less). ---------------- Actually you'd want to avoid using the trapped air under the driver as a port and limit the upper frequency. This would produce a form of a bandpass enclosure. If you calculate the mass of air in this space as well as the "exit" surface area... you will see that this is well beyond the sub's frequency response in most commercial subs. ---------------- On 7/30/2004 5:43:32 PM D-MAN wrote: the bottom firing version uses the floor and the cabinet to achieve a 1/4 space (2 angled surfaces) which is more efficient bass-wise than the free standing 1/2 space (1 angled surface being the floor) front-firing version. ---------------- Ummm... I don't mean to pick on you, but it is still just one acoustically "reflective" surface... (or 1/2 space as you refer) for both the front and bottom firing subs. NO SPL gains for either one Later... Rob Quote Link to comment Share on other sites More sharing options...
D-Rex Posted July 31, 2004 Author Share Posted July 31, 2004 ---------------- On 7/30/2004 11:50:01 PM formica wrote: BTW, I used the Stryke AV15 driver in a Klipsch Heritage inspired enclosure ---------------- This was the same driver I was targeting mainly because of it's attractive appearance. There are some others I have been considering but this one seemed to have the best appearance and the best specs for the price. However, I have been told it is currently unavailable and that the price I found at Stryke.com is last year's version that had problems. Where did you get yours and are you happy with it? I haven't seen a front firing that has a sealed enclosure, is there such a thing? I am assuming yours is ported, where did you get your ideas for the design and size of the box? Did you use one of those programs like unibox? Thanks, D-Rex Quote Link to comment Share on other sites More sharing options...
formica Posted August 2, 2004 Share Posted August 2, 2004 ---------------- On 7/31/2004 11:49:28 AM D-Rex wrote: I have been told it is currently unavailable and that the price I found at Stryke.com is last year's version that had problems. Where did you get yours and are you happy with it? ---------------- It is a first generation AV15, and I'm very pleased with it and have had no problems with it. I think the problem you mention was limited to a very small number of early units where the manufacturer used the wrong adhesive. They were repaired under warranty. Aesthetics is a personal thing as I personally prefer the "standard black" drivers... but the AV15's T/S parameters produced an enclosure which matched well with my size/efficiency needs. Given Hoffman's Iron Law it's a question of balancing the enclosure size, bass extension, and required amplifier power. Basically the smaller the enclosure, the more power you will need to achieve the same bass extension. I posted a comparison not long ago of several common drivers. Yes, my enclosure is a ported, and consists of a 6ft3 box tuned to 19.5Hz with a 700W pro amp. I used WinISD and Bassbox Pro to design my box... but then adjusted the tuning using test tones and a multimeter. You can read the detailed AV15 sub is ready... thread for more info. Fabulousfrankie actually had an AV15 (or was it the AV12) in a sealed enclosure for a while before he upgraded to the two vented units he now has. A sealed enclosure will be smaller but your f3 will be higher but at a slower slope. Try out a couple of drivers in WinISD and you'll understand what I'm getting at. Later... Rob Quote Link to comment Share on other sites More sharing options...
D-Rex Posted August 2, 2004 Author Share Posted August 2, 2004 ---------------- On 8/2/2004 11:31:27 AM formica wrote: ---------------- On 7/31/2004 11:49:28 AM D-Rex wrote: I have been told it is currently unavailable and that the price I found at Stryke.com is last year's version that had problems. Where did you get yours and are you happy with it? ---------------- It is a first generation AV15, and I'm very pleased with it and have had no problems with it. I think the problem you mention was limited to a very small number of early units where the manufacturer used the wrong adhesive. They were repaired under warranty. Aesthetics is a personal thing as I personally prefer the "standard black" drivers... but the AV15's T/S parameters produced an enclosure which matched well with my size/efficiency needs. Given Hoffman's Iron Law it's a question of balancing the enclosure size, bass extension, and required amplifier power. Basically the smaller the enclosure, the more power you will need to achieve the same bass extension. I posted a comparison not long ago of several common drivers. Yes, my enclosure is a ported, and consists of a 6ft3 box tuned to 19.5Hz with a 700W pro amp. I used WinISD and Bassbox Pro to design my box... but then adjusted the tuning using test tones and a multimeter. You can read the detailed AV15 sub is ready... thread for more info. Fabulousfrankie actually had an AV15 (or was it the AV12) in a sealed enclosure for a while before he upgraded to the two vented units he now has. A sealed enclosure will be smaller but your f3 will be higher but at a slower slope. Try out a couple of drivers in WinISD and you'll understand what I'm getting at. Later... Rob ---------------- YOU HAVE MY SUB!! That is quite ironic, I have been discussing building a subwoofer with Scp53 and this was the design I was envisioning. You even used plywood however, I have decided to go with the MDF and then apply 1/4 piece of plyboard over that as a veneer (unless there is a reason why I shouldn't.) But, I loved the aluminum cone and then wanted the cherry stain with the black front. You seemed to have it! Did you end up putting legs on the sub or did you leave it as is? I guess I have way too big of an amp (1000 watts from PE) but maybe someday I will get a second driver and make a double driver sub! Thanks for the link! D-Rex Quote Link to comment Share on other sites More sharing options...
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