18" woofer choices?

[Izzy Weird]

This topic is of great interest to me. I am shopping for subs too.

I especially enjoy reading discussions of the various JBL 18" drivers now offered, the 2241, 2242, 2258 (And comparisons to the 2245s I now use).

How about four of these 4645 single 18" cabinets in a line under the screen?

(In the past I have favored larger cabinets and an f3 0f 30 Hz. To me 8 cu. ft.
seems a tad small for an 18.)




Izzy

[LowPhreak]

How about four of these 4645 single 18" cabinets in a line under the screen?

Why stop at only 4...why not 24?

Unless you've got an actual movie theater or an airplane hanger to energize, what's the point? Two (one L ch., one R ch.) is plenty enough IMO. The money and space required would be put to better use otherwise.

[Titanium Dome]

Why stop at only 4...why not 24?

Unless you've got an actual movie theater or an airplane hanger to energize, what's the point? Two (one L ch., one R ch.) is plenty enough IMO. The money and space required would be put to better use otherwise.

I feel like a harpie, but I'll point this out again:

http://www.harman.com/wp/pdf/multsubs.pdf

LowPhreak, you've got one of the right numbers (two--the other is four) but not necessarily the right locations.

Please read the whole presentation, but the crux of the matter is in the slide and notes below. Sorry it's so wide, but I wanted it to be legible.

[4313B]

I feel like a harpie, but I'll point this out again:

It doesn't do any good. We've been over this since 2000 on this forum. It's now 2006 and we're going over it yet again.

This topic is of great interest to me. I am shopping for subs too.

(And comparisons to the 2245s I now use).

What is wrong with the 2245H's you now use? If they aren't doing it for you then you aren't using them right.

[Ken Andrew]

Many commercial subwoofers seem to work in the 50-100 hz range and they offer are no improvement to my stereo listening experience. I want something in 16-50 Hz range (even if it means lower efficiency or reduced output).

I recently went to a dealer in PA speakers and 'appraised' several dual and single 15" and 18" JBL woofer combinations in cabinets as bottom end support (ie. 50 Hz down) for my venerable 4315.

The first thing I noticed was the dealer used MP3 encoded CDs as demo material. The other customers were half my age so perhaps he was responding to the PA/disco market who want convenience before quality.

Using normal CDs I found that all of the PA subwoofers had the same problem - the sub-bass was either inaudible or full-on demolish the house. I guessed this is because of their fantastic efficiency, the inertia of large cones, and the need for extreme volume in normal use.

IMO in a theatre or concert this all or none output would not be an issue. But at home in my study where I might want to read a book or answer the phone while listening to music, the sound output has to be controllable from 'background level' to 'shouting level'.

Does your recommendations match well with existing full-range speakers ?

[4313B]

Many commercial subwoofers seem to work in the 50-100 hz range and they offer are no improvement to my stereo listening experience. I want something in 16-50 Hz range (even if it means lower efficiency or reduced output).

Honestly? Get yourself a pair of W1500H's if you can. Maybe someone will sell you a pair of SUB1500's which would be a very decent second choice. That's what I would run with 4315's. Don't forget to try blocking the ports on the 4315's after adding in subs.




The 4645C is a really big box. It is a very good box. If one can fit a pair of 4645C's or S1S's into your environment and have a decent variable low pass one will find that they are quite nice. Read the 4645C product brief and understand it. One might find that crossing the 4345C over real low with a shallower filter than what is popular these days ends up giving them exactly what they are looking for.

http://www.jblpro.com/pub/cinema/4645c.pdf

Now, do I have to list ALL the JBL subs I've used incessantly over the years in order to make my point here? I've recently learned that there are other people on this forum more than willing to dispense information regardless of the fact that they've never actually touched some of these drivers coupled with the fact that they have no bassline (mispelling/pun intended) for comparison.

[LowPhreak]

LowPhreak, you've got one of the right numbers (two--the other is four) but not necessarily the right locations.

Well, I'd say sub placement is never really a hard & fast rule; it's very dependent on room size, shape, damping, wall materials, speaker response, listener preference, blah blah. One of Audio's 4 1/2 Basic(ally) Complex Food Groups.

What I do if the room allows it is start placement with the Rule of Thirds, or other calculations to try to ameliorate standing waves as much as possible, unless the manufacturer recommends a specific placement. That's the 'science' part; the other is the 'art' of listening to get the ultimate placement position(s) in a given space. Sometimes an EQ doesn't hurt either, along with a few splashes of Snake Oil over my left shoulder.

I think it was Legacy Audio speakers where I read once that they had done several measurements/experiments with any number of bass drivers employed at once in a system, where their conclusion was that to get any significant gain in efficiency/output (starting with a single woofer), you have to go to 2 woofers, then 4, then 8, 16, and so on...ie: doubling. Other words, going from 2 woofers to 3, or from 4 to 6 didn't produce great results. Sounded about right to me, knowing how audio demands doubling of output power to gain 3dB.

Which is why (simplistically stated) I've always noticed guys who've mounted a row of 3 woofers in their cars haven't sounded better or gotten higher SPL's than those mounting only 2 of the same drivers and similar power amps/X-over. Why waste your time with 3? Just buy the extra driver and do it right!



But this ain't a car audio forum...oops!

Now, do I have to list ALL the JBL subs I've used incessantly over the years in order to make my point here? I've recently learned that there are other people on this forum more than willing to dispense information regardless of the fact that they've never actually touched some of these drivers coupled with the fact that they have no bassline (mispelling/pun intended) for comparison.

It's good to see that at least someone here has had experience with the 2242H/4645C/S1S flavor, and can comment accordingly.


Ken Andrew -

I'd have to say that of all the subs I've owned or heard in a domestic environment, for the low bass range - meaning 40Hz and down - the pair of the esteemed REL Stentor III's I once had was my fave - even more so than the Kinergetics SW-800 towers I owned previous to the REL's. They integrated perfectly, accuracy and timbre was stunning, and I couldn't believe what they did for the soundstage. Played plenty loud too.

You should give the Stentor III or Studio III a serious listen if you can find a dealer that has them, if that last 20+ Hz of the spectrum is your huckleberry.

[4313B]

It's good to see that at least someone here has had experience with the 2242H/4645C/S1S flavor, and can comment accordingly.

Um, actually, I think there may be at least a baker's dozen who can now comment on the 2242 based on actual real live personal experience. And some of them are a wee bit more articulate than I am.

I think it was Legacy Audio speakers where I read once that they had done several measurements/experiments with any number of bass drivers employed at once in a system, where their conclusion was that to get any significant gain in efficiency/output (starting with a single woofer), you have to go to 2 woofers, then 4, then 8, 16, and so on...ie: doubling. Other words, going from 2 woofers to 3, or from 4 to 6 didn't produce great results. Sounded about right to me, knowing how audio demands doubling of output power to gain 3dB.

Sounds like they read John Eargle's papers just like the rest of us have.

[JuniorJBL]

There are quite a few here on this fourm that use these drivers.

I for one use 2 2242's and the 4645c cab design is really good. I have built one other @14cu ft that doubles as a demolition tool , but it is a very BIG box. (it also weighs 310 lbs)

OTOH I also have 4 sub1500's in 2.2cu ft sealed boxes and they work very well too.

So it becomes a preference of what size box you want and what size your room/WAF will support.

[4313B]

See, with guys like that who have actual real world experience and who can post without pissing anyone off all I have to do is sit back and post emoticons!

Thanks JuniorJBL

[JuniorJBL]

Glad I could help

[Don Mascali]

I use two 4645C cabinets in my Music/HT system and they are incredible. Room gain keeps them relativly flat in my 18'x22'x8' room. JBL says that the alignment will support equalization to bring up the bottom if needed. As long as a High Pass 20HZ filter is used. I personally use a 48db 20HZ cuttoff to 80HZ X-over.

The bass can be down right scary and in Videos like the StarWars series where things go boom the pressure waves tickle my beard . If a rational setting is used they seem to dissappear but make their presence known when the program material requires it.

I used two B380 clones I built in the 80's, for many years and it was a quantum leap up to these.

I have never heard the 1500's but I can recommend the 4645C with no reservations.

Too much is just right.

[4313B]

Thanks Don!

[Mr. Widget]

There are quite a few here on this fourm that use these drivers.

I for one use 2 2242's and the 4645c cab design is really good. I have built one other @14cu ft that doubles as a demolition tool , but it is a very BIG box. (it also weighs 310 lbs)

OTOH I also have 4 sub1500's in 2.2cu ft sealed boxes and they work very well too.

I use a pair of Sub1500s on a regular basis and find that they can put out deep tuneful bass beyond any reasonable need I may have in my fairly large listening room. I use a pair in ported 5 cu ft boxes tuned to 20Hz for HT use and recently started using a pair in 3 cu ft sealed boxes for music. In the sealed boxes I do give them a 3dB lift at 30Hz. In both cases I love these things.

I have also recently built 4 dual 8 cu ft ported cabs for 2242s that will be going to a forum member for a fixed installation. These things will crush the Sub1500 for maximum output and are absolutely necessary for a large commercial venue... that said in my residential setting I much preferred the sound of the Sub1500. They may be hard to find, but the W1500Hs should be available soon and are its new replacement. Don't get me wrong the 2242s are stunning... and mind numbingly powerful, but for quality tuneful bass, I have never heard better than the Sub1500.


Widget

[4313B]

Excellent!

Thank you sir.