Looking for opinions on this atricle/subwoofers

Tony455

Hi checking to see if there is agreement on this article. https://www.avnirvana.com/threads/what-are-your-favorite-subwoofer-drivers.2326/ Seems that he is saying your better to use live music woofers than ones designed for home use.

jr@mac

Disclaimer: I read only the first post.

I agree with his requirements - with a caveat. It appears he is designing around a very high SPL level. This is common in DIY design, we tend to do our modeling by pushing boundaries of SPL, especially in the lower octaves. I adopted a 93db/1M approach several years ago based on a single afternoon of listening at what I thought was a high volume while also keeping my SPL meter next to me. I listened then at about 9 feet, and even on highly dynamic and/or compressed music I rarely pegged 85db on the meter. This guy is targeting some serious output, hence his medium sized live venue bass driver requirements. I don't know about the rest of you, but when I used to mix live music in medium sized live venues I never pegged more than 100db at my mixer station, was probably around 106-109 on the dance floor. If he is imposing (and routinely exploiting) those capabilities on his home system, bass distortion will not be a problem after he goes stone deaf at a young age. After a two show weekend, my hearing would be kind of shitty for a few days and I am positive I caused some permanent damage as a result. Just one of many reasons I left that part-time job.

One nitpick: shorting rings mean fuckall for the bottom octave or three so I have no idea why he makes that a requirement. They can make it easier to cross passively if you are using your 18" drivers up to the lower mids, I suppose. Bass distortion is largely driven by motor strength, and soft part linearity at excursion. I suspect modern subwoofer driver designers throw a shorting ring or two in there to pander to modern expectations of what makes a driver "high end". I had a chat with Rory one night about that very topic, not to pull an "argument from authority" but he is one of the few people in my circle that has experience in transducer design.

That all being said, the best bass I have ever heard was a Lindsey Sterling concert. My phone indicated strong output at my seated position nearly to infrasonic territory and it was generally in the 90's peaking output. I have no idea what the system was, but likely a battery of JBL 18" drivers since nobody really does it better.

Tom_S

I was used to running the typical 2x18 boxes with Rock & Country bands in dance halls and bigger bars. I almost always had enough rig for the gig, as they say. But it was always actual live instruments, not DJs. The HP on DSP for the subs was always around 35 - 40Hz. I wasn't trying to hit the bottom octaves like in a high-end home theater. Seeing that it take 4 times the displacement to hit the same SPL an octave lower, I can understand why these guys are using big pro-sound drivers to hit 20Hz and below at acceptable distortion levels.

dcibel

Looks like the PA465S-8 was on sale at a heck of a deal, and is now sold out. Hope they aren't discontinued, even at regular price they're pretty good value. A bit higher Mms though than most competing 18" subwoofers.

I once sold a guy on a pair of them for his HT, and they weren't enough, though the problem was very much due to the room and placement than the drivers. Also, even though this person said he wanted a HIFI system, it became very clear that he was much more interested in being the loudest than anything remotely HIFI. The pair were in a big ported cabinet installed under the stair cavity. Problem was that he wanted to elevate them off the floor so the kids wouldn't kick/poke them, and 2 opposing corners of the HT room were open to adjacent rooms without doors (what was he thinking?), so this installation lacked a lot of boundary reinforcement. Anyway, I thought they were great value and were used with a PA amp with integrated DSP, I think it was a Crest, can't remember.

Designing a high SPL system the extends below 30Hz without major compression and other issues can be a real challenge. Port sizes become unreasonable to fit in a cabinet and avoid resonances in the sub frequency band, and passive radiators are great but get expensive. Anyway, I find even for HT 30Hz is a great compromise, I'm not really into the sub-bass synth noises that most modern movies contain anyway. With 30Hz in mind, RSS390HO looks pretty good to me

dcibel

Using pro drivers for this application usually will require some EQ to get the low end bass, so the response that you get from your cab isn't so much important as the max SPL at any given frequency, that will determine how much EQ to can apply and how loud it will go once you do so.

rjj45

I'd have to run the specific models to be sure, but in the past, some of the pro and semi-pro drivers like the famous Eminence Lab15 were found to not be very good for the smallish boxes in modern living rooms, but were better suited for folded horn bass bins ala Bill Fitzmaurice. Certainly if you want >120dB bass that's what you have to do for a residential setup.

Tony455

Thanks for the comments guy's.I'm semi illiterate when it comes to graphs and numbers,thought I'd get some expert opinion on this. Just thinking the best way to go in a sub definetly not looking for rock concert volume.Do like live music sound at home though.Small box subs are a trade off but,if they can get a nice bass with some of the lower octaves from piano. And do justice to Pink Floyd I'll be happy.

ugly_woofer

If you have attic space above or basement space below infinite baffle takes zero space in the living area. I run 2 Dayton ib15's in my attic above my home theater room and it's plenty for me.

dcibel

Do the neighbours enjoy it too?

Kornbread

Ha ... had to move the IB out of the shop because it was rattling the neighbor's trailer.

ugly_woofer

My neighbors are about 500 ft away on both sides, so I never considered it, but I'm going to have walk outside next time I watch a movie.