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Home » Audio » Speaker » Optimum range JBL 2226
| Optimum range JBL 2226 [message #61779] |
Wed, 27 January 2010 18:14  |
SteveBrown
Messages: 330
Registered: May 2009
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Grand Master |
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I did a couple searches with no results, though I'm sure this has been discussed before. I have a pair of 2226's. I have a feeling they take a good bit of power to get the stiff suspension to really take off. Playing at 90db is a lot more fun than at 75db and a 30w amp makes these come to life more than a 2w amp - nevermind the 97db spec. Have others found that to be ture? But my bigger question goes to this, what is the optimum range for these guys? I see stuff that says 600hz tops, and not below 60. I see specs that seem to suggest 45 on the bottom is easy, and up to 2.5k on the top. So what is really the best bet? Here is where I'm going on this... in a two way system, do I really want a 0.5way speaker? I mean, if it is really only good for 70hz to 600hz, and needs 30+ watts, should I sell these and get a different woofer?
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| Re: Optimum range JBL 2226 [message #61781 is a reply to message #61779] |
Wed, 27 January 2010 20:02  |
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Wayne Parham
Messages: 18787
Registered: January 2001
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Illuminati (33rd Degree) |
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As you know, I have a lot of experience with the JBL 2226 woofer. I've used 'em new, old, run with only flea power, beat to snot with arc welders, reconed, re-dust-capped, etc. So I think I have a pretty good handle on these woofers.
To use them just to 600Hz is a waste, in my opinion. Any old woofer will reach that high. The real strength of the 2226 is how well it behaves up high, not down low. It truly is a midwoofer.
That said, in my cornerhorns, they're only used up to about 300Hz, but it's with a first order slope so there's a pretty fair amount of overlap. Still, I think the main thing that sets the 2226 apart from most other woofers is its ability to play clean through the midrange.
So the range is definitely 40Hz to 1.6kHz. Now, mind you, at the top end, the beamwidth is definitely narrowing. That is a good thing when used properly, matched to the next adjacent subsystem. These things can easily be crossed anywhere between 800Hz and 1.6kHz. Response up there is very smooth, cone motion is well damped and it sounds nice. Beamwidth is just where you would expect for a round direct radiator, about 90° around 1kHz to 1.2kHz or so.
As for power, I think they sound just fine with flea power, even down to those little 2 or 3 watt 45 and 2A3 amps. But to me, that's just not enough power for a 97dB speaker. It's just a simple matter of headroom to me, you just don't have enough oomph. But for low volumes, it sounds fine. Give 'em 10 or 20 watts and they're getting enough power to play quite loud.
One thing I do see, on a similar note, is these woofers really have stiff suspensions when new, straight out of the box. I generally make speakers that are slightly overdamped, a conservative alignment with gradual rolloff slope. This allows for electro-mechanical shifts from (high power) heat and other conditions. But the 2226 is so stiff when new that they measure slightly underdamped. In a more traditional cabinet tuned closer to max-flat alignment, they can sound really thumpy at first, with too much 80Hz midbass from the excessively stiff suspension shifting the system towards being pretty heavily underdamped. So if you're using a low-power amp, give 'em some juice for a while first. They won't sound all that great until you do.
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| Re: Optimum range JBL 2226 [message #61782 is a reply to message #61781] |
Wed, 27 January 2010 22:00 |
SteveBrown
Messages: 330
Registered: May 2009
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Grand Master |
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Thanks, Wayne! I know you're a 2226 guru, so I appreciate the input. Mine are at least 5 years old, so I think they're busted in. In fact, one still has a dust cap with a finger hole from a 5-year-old in it (no, it wasn't Eddie). But I don't find them wonderful at late night low levels, and I'm still working to find just the right way to cross them to the higher speakers. I've been playing with some Fostex FE167's Open Baffle crossed at about 1200 khz (1st order). Okay, but in my small room, I think they need more space to really showcase the open baffle bit. I'd love to use the horns I have but again, the small room isn't ideal, unless you want a laser beam right between the eyes. What I'd really like to find is a good "normal" tweeter to pair with it, like the old Dynaco A25 (which I've been experimenting with). First order on the tweeter, no crossover on the woofer, cross about 2.5khz. Do you think the 2226 is okay to 3khz? I've got some Aurum Cantus GS2i (I think) ribbon tweeters of similer effiecency, but hesitant to toss them in there due to the intollerant nature of ribbons crossed too low. Any thoughts are appreciated. I don't think horns (given my smallish room) are for me.
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| JBL 2226 Usage [message #61785 is a reply to message #61784] |
Thu, 28 January 2010 19:10 |
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Wayne Parham
Messages: 18787
Registered: January 2001
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Illuminati (33rd Degree) |
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I meant to say this earlier, but then got busy with my morning things and just clicked "send". I wonder if what you're hearing (or missing) at low levels is a Fletcher-Munson thing. I could understand that, 'cause the deep bass needs more volume at very low power levels, according to the Fletcher-Munson curve and 2226's are really midwoofers. They're detailed to my ears even at the lowest levels. But deep bass drivers, they're not. Might try and add subs and see what you think.
Your three-way approach might work nicely too though. One thing I like about that is it gets all the vocals and most instrument fundamentals from one source, the midrange or fullrange driver. The woofer just covers the modal region, which is an entirely different animal. So it lets you deal with that specifically, and just by having the two sound sources overlapping in the upper modal region, you'll get some smoothing. Just run a first-order low-pass on the woofers somewhere in the 150Hz to 200Hz range and let the mids run all the way down, overlaping as far down from there as they'll go. This give more sound sources below the Schroeder frequency, which most agree is a good thing.
As for polarity, yes, the 2226 has what most would consider to be reversed polarity. Positive on the black terminal gives forward cone motion. So in general, you'll want to connect the woofer with positive to black. But when you start measuring stuff, sometimes you want it the other way around depending on driver spacing and crossover phase.
If you crossover as I suggested around 200Hz with a low-order low-pass on the woofer and run the mids all the way down for overlap, this becomes a different issue, even more complex because it includes room modes. It is non-trivial to know what is the "right" or "wrong" way to connect, because what combines constructively in one area of the room will probably combine destructively in another area of the room, forming modes.
Room modes are why it is good to have several sound sources, because where one driver self-interference (from a wall, ceiling or floor) forms a null, another driver self-interference may form a peak, somewhat averaging to smooth the overall sound field. This kind of thing only happens from about 200Hz down, and so this peculiar arrangement using several sound sources having several phase relationships only really works in these lower frequencies. Above that, you really want a single sound source, or where multiples combine, they should be in phase.
Long story short: Remove the 500Hz crossover and instead use a 5mH coil in series with the 2226. Don't use a series cap on the FE167 - let it run all the way down. I'll bet a months worth of lunches it sounds waaaaaay better that way.
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