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View Full Version : JBL 2245H and corner placement etc



Niklas Nord
12-10-2003, 08:13 AM
There was someone that was telling me that the
2245 would be hard to place in the corner, that it
would be hard to tune with the room..




Now, today i will start working on my new listeningroom.
i will put damping panels on the walls. i may put out some
pictures when itīs all done.

NOW then

behind the K2īs there will be two subs in the corners..
if they will be bassreflex, Iīm aming @ cirka 380 liters
and tuned to 20hz ..
I dont think i can live with some selaed ones, this is
becouse i tend to play rather loud.

What do you think about a box in the 300 - 400 liter way?
And shuld it be tuned to 20hz ?

Sub will be used upp to max 80hz

4313B
12-10-2003, 08:51 AM
Sure, give it a try.

Tuning to 20 Hz would be a good place to start.

Niklas Nord
12-10-2003, 08:53 AM
And a big big port..

4313B
12-10-2003, 05:16 PM
Any port in a storm...

Niklas Nord
12-10-2003, 05:29 PM
it seems that all kind of volumes between 250 and 400 would fit.
There is small differences..

Confusing..

Hard to get the one thatīs the best one..

4313B
12-10-2003, 05:40 PM
Until you build a test box or two you have no baseline...
Why don't you ask Neriks if you can pop your 2245H's in his boxes and see what happens? That might be a bit much to ask since they are so cherry, but maybe he would be up for it... I can't remember what his volumes and tuning frequencies were so you will need to find that out.

4313B
12-10-2003, 05:56 PM
This might help to illustrate what can happen when placing the 2245H in a corner. Keep in mind that the 2245H has a nice flat linear response whereas the 2242H has a gentle tapered response. Technical Note Volume 1 Number 22 (http://www.jblpro.com/pub/technote/tn_v1n22.pdf)

mikebake
12-17-2003, 05:01 PM
Okay, I printed and read the tech note, and I get most of it; of interest to me is that the 2227 is not a drop-in for the 2226, as the 2226 WAS a drop-in for the 2225. Anyway, the 2242H is obviously another great JBL driver, but I didn't see the comparison of the 2245 and 2242 as pertains to response and effect on corner placement. I take it you meant that the 2245 is already fairly flat and doesn't need/like the corner, and the 2242 tapers on the low end and thus benefits some from the corner.....

4313B
12-17-2003, 05:09 PM
Originally posted by mikebake
I take it you meant that the 2245 is already fairly flat and doesn't need/like the corner, and the 2242 tapers on the low end and thus benefits some from the corner..... Exactly Mike, that's what I was trying to convey. The 2242H has the type of sloping response that makes it much easier to use in multiples and/or with corner placement.

mikebake
12-17-2003, 05:18 PM
Would that tapered response been one of the actual design goals, then?
I just finally brought one of my 2245's in from the workshop to put to use for HT. I have it about 5-6 feet from the corner, close to the back block wall (basement). Will fire it up tonight and see how she goes. Unfortunately, unlike my other HT processor, the 5.1 receiver in this particular room doesn't have stereo sub output, so I only brought one 2245 inside, plus I only had one spare remaining non-pro/non-fan amp left to use. I'll see how the single sub does, but I'm a fan of stereo subs. It's a mid-fi system anyway, so no biggie.
I am also considering trying nearfield subwoofing (sub behind and facing the back of the couch), a technique that Mike Bates on the High eff. Forum has commented on frequently and encouraged me to try. He really likes it, and it keeps overall SPL lower for the benefit of the rest of the household!

4313B
12-17-2003, 05:57 PM
Yes, I believe that type of response is evident in all the current JBL LF transducers.

It isn't a problem to run two subs off the sub output of the AVR Receiver. I do it all the time. See how a single behaves and then add the second one.

mikebake
12-18-2003, 09:06 AM
Using a Y cord to split, or what?