The sound is surprisingly cohesive for such large speakers.
I'm hesitant to pick up the bass bins because I don't have a place to put them in this layout. If I put them under the speaker the tweeter would be up on the ceiling 😂. Which might be okay as they can be tilted down and I think they are designed to work that way. But as I live in an apartment building I really try to keep 100 Hertz down in the dipole format.
I'm hesitant to pick up the bass bins because I don't have a place to put them in this layout. If I put them under the speaker the tweeter would be up on the ceiling 😂. Which might be okay as they can be tilted down and I think they are designed to work that way. But as I live in an apartment building I really try to keep 100 Hertz down in the dipole format.
The ideal thing from a practical living perspective would be meh midbass approx 80-250hz. I know that the mid-range wave guide won't provide pattern control much lower than 250 but would there be benefits from a wavefront/phase perspective?
Then I could put open baffle or ripole subs around my room.with DSP.
Then I could put open baffle or ripole subs around my room.with DSP.
The 4632 waveguides is very much like the JBL 2374, you will find a little info by searching.
It's similar to it's bigger 'cousin' the 2384, which you can gid a lot of info up on, try here, and audioheritage.org.
And no they have JBL's SSC (Screen Spreading Compensation) 'patent' they are designed to be behind a cinema screen or similar, so the directivity narrows up top by design, to compensate for loss of high frequency through acoustical resistance.
Look at the directivity index etc. at the bottom.
go to JBL's site and dig out the info from they're 1" waveguide cinema line 37xx, it's the pretty much the same waveguide.
Just using a 1 3/8 thread on driver instead.
As for your space issues, in a normal room, the double waveguide with 2x165H's usually makes one able to fit the bass bins underneath.
If you care to dig on archive.org, you will find some currently unavailable technotes touching on the optimized aperture waveguides etc.
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Thanks so much I will look at the archive info today as I was trying to figure out what the hell optimized aperture waveguides means.
On the screen spreading comp would that be what's causing the roll off that I see? I was only able to get a very rough RTA capture from white noise at my listening position.
Do you think this is caused by me listening off axis then?
High to mid cross at approx 1kish
On the screen spreading comp would that be what's causing the roll off that I see? I was only able to get a very rough RTA capture from white noise at my listening position.
Do you think this is caused by me listening off axis then?
High to mid cross at approx 1kish
Attachments
I would advice you to do some searches on audioheritage.org forums, generally the best source for things JBL related, there is also plenty of datasheets etc. Need to be a member to access some of it.
I have not played with your exact version of the Waveguide.
Also be aware your waveguide is asymmetrical, 90 x50. it has 20 degrees and 30 degrees, up or down depending which way you mount it.
Crrect definition by JBL is a Progressive Transition (PT) Optimized aperture waveguide 🙂
If that is with the 2425HS you will notice it does not have a very extended top end for being a 1", also it is missing the newer JBL's Coherent wave phasing plug.
Falling top end response is normal with compression drivers, once you pass the mass break point.
Also the waveguide will make it drop 6db /octave where the directivity is constant or close to.
The response is rather close to the 4632 measurement by JBL, so close to expected? look at the 4632 pdf i added.
The SSC is the spike you see 12-14k in the directivity index in the newer ones (missing a bit in the 4632 sheet due to the lack of HF), narrowing the pattern, for more acoustic energy.
It is 'hotter on axis the off axis, to compensate for loosing part of the top octave being behind a screen/ acoustical resistance.
https://www.audioheritage.org/vbulletin/showthread.php?23546-Screen-Array
https://web.archive.org/web/20050204223944/http://www.jblpro.com/cinema/SA.htm
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I move them to quite an unusual toe-in for my room
I'm just waiting on it interface so I can run some measurements
If anybody would like measurements I can try to run them though no pro if you know what I mean
I'm just waiting on it interface so I can run some measurements
If anybody would like measurements I can try to run them though no pro if you know what I mean
I recently purchased these from cooper. There doesnt seem to be a ton of people with these in a house. I plan on finding a pair of 4648 or 4639 to use as the bass cabs. I mainly grabbed them to play around with, and see how they compare to altec a7-500's. I have never tried bi-amping and wanted to give it a whirl.
If you decide you want to upgrade the tweeters, you can swap in radian aluminum diaphragms, though you may find a more recent budget tweeter, like some of those from LaVoce, Faital, or Celestion, to be a better performer.
I have 2 pair of 2374s and several 1" CDs to match, was thinking about an MEH around it, though the XO might need to be a bit low because of the longer screw-on throat.
I have 2 pair of 2374s and several 1" CDs to match, was thinking about an MEH around it, though the XO might need to be a bit low because of the longer screw-on throat.