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Niklas Nord
04-26-2003, 08:37 AM
Here in sweden the 2235 and 2245 are really hard to get,
well there are some 2225 out there to be reconed, but
the 2245 are HARD HARD HARD to get.

Well, i MAY get my hands on two 2245, and then i will be happy!!


Is there any sonically difference between the 2235 and 2245 ?
I´m planning to use subs in the corners of the room.

Are the sound as good, but the 18" moves more air ? Or is
there any possibility to go lower with the 18" ?

THEN there is that hole graal - the massring of the 2235 that
makes it a FS17 -driver.

A 2235H 17FS driver vs the 2245H driver ?????


I will maybe move to a bigger house, and want some real action

4313B
04-26-2003, 09:27 AM
The published Fs of both the 2235H and 2245H is 20 Hz. In reality it is more in the 16 to 18 Hz range. I've never measured one above 20 Hz.

Yes there is a sonic difference between the 2235H and 2245H. Compared directly the 2245H is significantly more effortless but until you A/B them the 2235H sounds mighty fine. The 2235H has a slightly more powerful motor and sonically this translates to what I term a "quicker" sound quality. Both are fantastic transducers. What it boils down to for me is real estate. If you can live with 5.0 cubic feet go with a single 2235H, if you can live with 8.0 cubic feet go with a single 2245H, if you can live with 10.0 cubic feet go with dual 2235H's instead of a single 2245H. If you can live with 20.0 cubic feet then opt for dual 2245H's. It really is pretty much that simple. Both are capable of the same VLF bandwidth neither has a bandwidth advantage in the VLF, the 2235H has a bandwidth advantage in the midbass. The 2245H handles more power and is more efficient.

Mr. Widget
04-26-2003, 10:50 AM
I have the dual 2235H set up. It is fantastic. I my rather large room however it is possible especially on movies to demand too much of them and get them to bottom out slapping the mass ring into the pole piece with a loud thwack!

Realize at this level plates, furniture, and even the walls and skylights in my house upstairs are groaning and coming unhinged. Down stairs it sounds great upstairs it sounds like an earthquake and I can only take full advantage when my wife is out of the building.

Niklas Nord
04-26-2003, 03:02 PM
Mighty Mr Widget!!

That is really something!! Things are supposed to shake
ant rattle when you run these big JBL drivers!!!

Sound great!

What movies do you like then?
Any musicvideos on DVD perhaps ?

Mr. Widget
04-26-2003, 04:31 PM
"What movies do you like then?
Any musicvideos on DVD perhaps ?"


One of my favorite movies is "The Player". No deep rumbles there, however for impressive sound and a decent movie, "The Matrix", "The Fifth Element", and "The Lord of the Rings" are all very good. The other night we watched "Spy Games" . It has a very good soundtrack with very believable foley work.

I am not a fan of music videos, however I do own a few concert films. Watching "U2 Rattle and Hum" at 10-15dB above THX reference (peaks of 115-120dB) is really close to being there. Since there is no subterranean bass the subs handle it fine and my front three channels are capable of over 130dB in a room my size. (No I have never verified this.)

Ian Mackenzie
04-26-2003, 08:07 PM
Where's the cat when this is happenng...Muhhahaha

"I have the dual 2235H set up. It is fantastic. I my rather large room however it is possible especially on movies to demand too much of them and get them to bottom out slapping the mass ring into the pole piece with a loud thwack!"

A high pass filter can help reduce undesirable or non linear excersions in the VLF zone...this make help.

To illustrate this point, assuming the box is tuned where the resonance equates to maximum loudness ie 26-29 hertz, a steep filter action below 26 hertz will protect the suspension at frequencies below the resonance where the driver is effectively un loaded. The B380 filter was set up this way.

At the resonance there is maximum loading on the cone and it should be nearly impossible to bottom the cone, however as you move up above resonance cone will be working harder and excursion will ramp up and the port action will reduce, but also the cone excursion will reduce with rising frequency.

Doubling cone area reduce excursion by a factor of 4.
I have never seen my 2245s move appreciably, however set up as ELF aka B460 I have seen in a B460 the 2245 move a FULL INCH!!! Not for the faint hearted and you need massive power reserves.

It was scary, the lights dimmed momentarily and my pants and everything at ground zero were resonating like crazy, about 5 minutes later the poweramp , a bridged 200 + 200 (720 watts) shut down, the heatsinks were too hot to touch, then the Cops came.....I mean hello, I recall they came in through the front window and one Cop said F................., look at that woofer man.. sh......t. We were more worried about the amp, it was close to smoking.

The 2245 survived to live another day because it was set up correctly.

I hope that made somc sense.....its easier to illustrate on BassBox. 5.1. The point is never drive the cone with signal below resonance or you risk damage, and make sure you have power on tap.

Ian

Mr. Widget
04-26-2003, 11:41 PM
While I am sure adding a high pass filter would allow me to play the system louder, I would rather turn it down. I have never bottomed out the 2235Hs with music as there isn't usually very loud musical information below 29Hz (the tuned frequency). As far as movies go, peaks at THX reference (105dB) are fine. I have to play an explosion or other infrasonic source a few dB louder than that to cause the bottoming out. At this point the room is quite pressurized!

I didn't bring this up as a problem for me, but from reading other's posts there are those out there who have very extreme needs. For those that need even more ultra deep bass I would recommend one or two 2245Hs per side.

MikeM
04-27-2003, 01:42 PM
Why not just build 5 cubic ft cabnets and stack the 2235H to the ceiling. Say 6 a side. Years ago I ran 2235H connected to 1K mono's and was able to drive the amps to rated sustaned. police would just shine the light in the window evertime they went by I turn it down then right back up. Woofers held up for years. Now my wife said she heard my music 3 blocks away while taking a walk. only time I can enjoy the system

Niklas Nord
04-28-2003, 12:02 AM
Has anyone been trying in an sealed box, and with
linkwitz transform.

well, maybe the 34 and 45 do not have the excursion needed,
and sice they behave so well in ported box, it mey not be
better at all..

4313B
09-01-2003, 08:55 AM
"Has anyone been trying in an sealed box"

Yes.



Niklas, have you seen these yet:

Loudspeakers on Damped Pipes – Part One: Modeling and Testing

Loudspeakers on Damped Pipes – Part Two: Behavior

George Augspurger presented these a few years back.

G. L. Augspurger
Loudspeakers on Damped Pipes, Part One: Modeling and Testing; and Loudspeakers on Damped Pipes, Part Two: Behavior
AES 107th Convention
Jacob K. Javits Center
New York, New York
Sept. 24 - 27, 1999

Preprint Number: 5011 Convention: 107 1999-09
Author: G. L. Augspurger

http://www.aes.org/publications/preprints/preprints_search.cfm

Niklas Nord
11-24-2003, 02:22 PM
Ahh, i did not se your post here..