Multi way horn laboratory - aka man cave

[frangus]

Swell. I'd be grateful if you could post measured FR for these + pictures of the diaphragms.

(From the same seller) I have 2 cores and 3 diaphragms:

1 that looks normal, measures as expected (good, but with ragged HF)
1 that has an unusual rib pattern; HF measures better (less droop + much smoother >10kHz)
1 that has an unusual rib pattern; HF measures better when it works - but it is faulty (high Re and sometimes doesn't play at all - cracked VC wire?)

...and I'm curious about which type you got. I haven't yet been exhaustive so it may not be just the diaphragm that explains the measured difference.

Is your plan to run:

Ribbons
2"
15"
Subs?

I'm still modifying / extending my horns, they currently look pretty ugly. I'm thinking of running a 2.5way, hence am interested in getting the best HF I can from my compression drivers (without blowing my budget - e.g. on beryllium):

2"
12" (Faital)
12" (low efficiency SB)

Yes that's pretty much the plan. I swapped parts in and out over the weekend, measured, adjusted and listened. Conclusion was that I prefferd the EV 12" driver as a midrange over the horn loaded cone and comp driver. It just has a better illusion of scale from 500hz to 1000hz. The horn goes omni below 500hz but above this does a decent job. I tried with and without the ribbon and preferred with. I find the highs cleaner and smoother than either domes or compression drivers. More experimenting to follow.

I'll take some more measurements and photos of the diaphragm for you when I get a chance. Stay tuned 🙂

 

[frangus]

I have the celestion woofers installed and all sounds good without any measuring or tweaking as yet

I installed some room treatment and the effect is dramatic to say the least even when using the horns to control directivity down to 700hz. The source of the sound completely follows the recording and with eyes closed I can't locate the speakers.

The most intersting result was swapping the mcm waveguide for a a VERY wide angle visaton tweeter waveguide with the 1" RCF compression driver. The sound is so clear, clean and wide without any colouration. I'd like to experiment more with wider angle horns.

 

[frangus]

Time to cast a wide dispersion conical horn

 

[ewollowe]

How even/accurate do you expect to get it frangus?

 

[frangus]

How even/accurate do you expect to get it frangus?

Probably good enough for some experimentation. I'll use joint compound and sandpaper to level out the depressions and fill the gaps.

Hollowboy, see photos of diaphragms below. Both the same, both in good nick it seems. Are yours the same?

 

[hollowboy]

Your drivers do look like they are in good shape.

Thanks for the photos. The diamond-embossed suspension is the same, but mine have ribbed domes.

I think that means yours look like originals (or clones based on them), and mine are more recent (or clones based on them). I just posted a new thread asking for info on them.

JBL Factory Speaker Replacement Horn Diaphragm 2445, 2445J, D16R2445

JBL Factory Speaker Replacement Horn Diaphragm 2446, 2447, 2450, 2451, D16R2450

+++

Edit - poking around that website a bit more - yours might be the SS audio aftermarket parts. Some of those have the little "+" sticker on the positive terminal, whereas I think the originals simply had a dab of red paint.

 

[frangus]

Measurements of 2445J on VFM 2" bi-radial horn attached

1. raw on-axis and off-axis
2. CD response corrected
3. MiniDSP correction EQ screenshot

These are ungated taken at about 2" in front of the mouth

 

[hollowboy]

Measurements of 2445J on VFM 2" bi-radial horn attached

1. raw on-axis and off-axis
2. CD response corrected
3. MiniDSP correction EQ screenshot

These are ungated taken at about 2" in front of the mouth

2. Looks nice. We fuss about flat response to 20kHz, but adult men lose about a dB of HF sensitivity every year, so I dunno how much smoothness >10kHz actually matters.

Tips with posting images:

a) in REW, there's a capture icon, top left of the graph, that takes a screenshot of the graph - smaller image, correctly oriented.

b) in general (for stuff other than REW), I use the print screen key on the keyboard, then paste it into Gimp (any image software would do - Gimp is open source, has an amusing name, and is pretty useful). In Gimp, I crop it, edit it if needed, then save as a .jpg file, with the quality slider set to halfway (for substantial compression without being too grainy).

 

[frangus]

Some progress

The EV horns were a positive addition to the system. The cabinet is undersized for the 15's and thinking of switching to an open baffle or cardioid to take advantage of the high QTS and control the pattern in the lower range.

 

[djk]

The HP640 is a really good sounding horn.

I add 2" of expanding foam on the back side of that horn for damping and rigidity.