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buutinie
12-12-2017, 04:23 AM
Hi guys,

I was just wondering if anyone had something to say on this issue. I did not find too much intel on my questions, so I thought Id just ask you guys, maybe someone already tried this.

I am planning on building a pair of 4345s... I have all the parts except for the bass-units. I do have some 2240h that need reconing. So I know that you can recone the 2240h into 2245h which is the original build for the 4345. But: I could also recone into 2240h and just have 2240h instead of the 2245h. Has anyone tried this? Any comparison of the 2240h and the 2245h? Any hints and suggestions? Anything?

Thanks a lot! And have a good Christmas season out there. Terrible weather here in Germany.

Max

speakerdave
12-12-2017, 09:50 AM
If you can find some genuine 2245 kits, that would be the way to go. Failing that, for high output classic domestic JBL LF consider dual 15's, 2235's or 2234's. For music at hearing preserving sound levels one 2235 will do, and you could build the 4344. For movies (Jurassic Park, explosions, train wrecks, earthquakes) you would want to add subwoofers to avoid klanking the mass ring.

The 2240 is not suitable for said application. Read the brochures in the JBL pro components section of the library.

ivica
12-12-2017, 10:27 AM
Hi guys,

I was just wondering if anyone had something to say on this issue. I did not find too much intel on my questions, so I thought Id just ask you guys, maybe someone already tried this.

I am planning on building a pair of 4345s... I have all the parts except for the bass-units. I do have some 2240h that need reconing. So I know that you can recone the 2240h into 2245h which is the original build for the 4345. But: I could also recone into 2240h and just have 2240h instead of the 2245h. Has anyone tried this? Any comparison of the 2240h and the 2245h? Any hints and suggestions? Anything?

Thanks a lot! And have a good Christmas season out there. Terrible weather here in Germany.

Max

Hi Max,

Using 280 Lit box, tuned at the 35Hz some mid-bass has to be educed several dB-s (about 3.5dB) round 300Hz if used 2240H then 2245H, but due to the lower Xmax of 2240H, maximum acoustic level would be 'reduced' to about 119dB/1m, but I can imagine that for the 'home listening consideration' it would be accepted.
Using 2240H driver, the problem of the cone suspension degradation over time would not be the topic.
Neglecting (or EQ) mentioned mid-bass bump round 300Hz, with the mentioned 2240H, f3dB would be round 33Hz, almost the same as with 2245H, several Hz-s can be get with 2245H tuned at 28Hz....

regards
ivica

I can imagine that 2240H would be faster, as it has lighter cone assembly (about 20gr) and larger BL factor

speakerdave
12-12-2017, 10:58 AM
The 2245 data sheet in the library doesn't seem to be loaded right. Go to the one at JBL pro (Google it).

Ian Mackenzie
12-12-2017, 10:31 PM
Hmm

I think the make do phase has started

My advice is try not the urge of make do.

You will find your self yourself disillusioned

And we will have more Frankenstein’s woofer projects floating around in cyberspace

Edit: if you only want to try another driver ie a 2240
That is your call.

But asking for opinions when it’s not a suitable application and then convincing yourself it’s okay only leaves a lack of clarity for anyone else later on

I myself did not start of with a full set of the correct drivers

My original diy loudspeaker was a mish mash of different drivers, altec 515, Jbl 2397/2420

I got rid of the Altecs, acquired the 2245s, tried European a 8 in Audax mid driver

It was Okay

I then bought the 2405 slots

It was better

I then sold the 2397 and bought the 2344a bi radials

Soon after l got a pair of 2122H mid from a tent sale

I used the 2245, 2122, 2420 and 2344a combo for a while

That was a good loudspeaker

Then one day in 2003 l got an email from GT with the network schematics of the 4345

So l get the idea of using alternatives but don’t kid yourself it’s going to work as well or better than the preferred option.

I currently have sitting on the shelf Acoustic Elegance 15m Apollo drivers, Jbl 2216 woofers, Tad 4003s, Bill Woods 700 cast aluminium conical horns, various other drivers including century gold woofers, some 18Sound compression drivers, some synthesis surrounds.

That suggests l continue to enjoy the 4345 with all the various improvements and a number of new ones.