1,5" wave guide shoot-out

[Wardsweb]

That is dedication. Thanks for the info.

[jmpsmash]

Incredible work. Thanks for sharing.

[sebackman]

If there is any particular data of interest just shout. All of it is too big to email/post (450Mb) but I can supply parts to interested members, however not for general distribution for obvious reasons.

Just finished the first of two pairs of "Hotrodded" Array 4892 for my workshop (PRO1400 & 2450SL). With new diaphragms in the 2450SL's and new JBL wave guides they are just wonderful compared to just about anything. Crisp! Albeit I have to admit I cheat using BSS DSP in an active setup. Subs are 2 pairs of Array 4893 with dual 2217 in each and lots of power. Can't stop playing. :-)

Next stop will be to finish the clone "Hotrodded" 4367 with 4" driver and BSS DSP in a M2-type active setup. That should be interesting. I do like what I have seen in the measurements when it comes to the 4367 wave guide. I will post in the other thread when I get there.

Now, where to put it all....

[mefisto]

Hi Rob, let me join the chorus of praise for your efforts. Since you offered, could you provide the measurements of only the 2450SL on the M2 and 4367 WG? If this is still too much of data with all the different time windows/distances, what would be the best combination for ascertaining the on-axis and of-axis performance from let us say 800 Hz to 20 kHz? The intention is to build a two-way speaker.. Kindest regards, M

[Mitchco]

Hi Rob, Nice job! Love the large format driver on the M2. Makes me want to purchase a pair of those waveguides. I am not a user of this tool, but I understand one can import measurement data to show some nice polar response charts and other views: https://kimmosaunisto.net/ Not suggesting a make work project or if it is suitable for your purposes, just in case you hadn't seen it before... Kind regards,Mitch

[Robh3606]

Hi Rob, Nice job! Love the large format driver on the M2. Makes me want to purchase a pair of those waveguides. I am not a user of this tool, but I understand one can import measurement data to show some nice polar response charts and other views: https://kimmosaunisto.net/ Not suggesting a make work project or if it is suitable for your purposes, just in case you hadn't seen it before... Kind regards,Mitch

Hello Mitchco

I am running M2 waveguides with 476Mg's. Using a large format driver is highly recommended. They sound effortless and clean.

Rob

[Mitchco]

Hello Mitchco

I am running M2 waveguides with 476Mg's. Using a large format driver is highly recommended. They sound effortless and clean.

Rob

Hi Rob, nice! Thanks for confirming.

I will be giving the them a try with the 2453h-SL drivers. I don't think I need an adaptor or spacer...?

Looks like they are going for $269 at: https://reconingspeakers.com/product...-lens-5025594/

Kind regards,
Mitch

[Robh3606]

Hello Mitchco

I like the 2453-SL use them on PTH1010's Did not need a spacer on the 1010's. Don't forget the mounting plates. You will need them if you don't have an alternative.

Check the OD of the 2453 against the 435Be which is 4 1/4.

2453 S/B bigger with a 4" diaphragm might interfere with the mounting plate hardware to the horn. I don't have access to a mounting plate or a waveguide or 2453 to check the hole pattern diameter against 2453 OD.

I countersunk the mounting plate hardware and added helicoils to the waveguide so I could flush mount the 476Mg. PITA getting the 1/4 20's screwed into the driver through the plate.

Rob

[Mitchco]

Hi Rob,

Thanks for the info!

Kind regards,
Mitch

[sebackman]

Hi,

I made my own aluminium adapter plates with both the big and small JBL pattern. Screws into the WG are counter sunk and I use pin-bolts & nuts for the drivers. No problem to use either JBL 1,5" driver as the holes are offset.

And I would agree with Rob, the 4"drivers seem to like these new WG's. And no doubt the 4" drivers will be a better match for XO below 1kHz on either the M2 or the 4367 WG. In a 3-way (4-way) it may be less sensitive. In a 2-way it may prove important as few 12", 14" or 15" units can go above 1kHz.

476Mg is probably the best choice as you get almost the resolution of the Be (is the difference really audible ??) but no need a UHF as with Be. The Be's do fall off quite steep, but you can use DSP or passive filters (using the superior sensitivity) to compensate. My findings are that an introduction of an UHF (045) XO @11-12kHz sounds more "effortless". And I do use DSP.

2353SL does ned an adapter/spacer on the VTX WG but much less so on the M2. There is a pick-up from 10-12kHz instead. I have not measured them on 4367. Good alternative.

Hence I will not go Be in the new builds. Now if I could only find a set of Mg diaphragms...

[Mitchco]

Thanks for the additional info! The M2 will be quite a change I suspect from the 2384's I am using now.

On another forum, user notnyt measured a few JBL CD's on the 2384 and had this to say about listening impressions:
https://www.avsforum.com/threads/jus...#post-42167329

If you scroll back through the thread there are several measurements to go with the comments. Don't know if the comments make sense, but it was enough for me to remove the 2432H CD that were on the stock 2384's (sounded harsh) and try the 2453H-SL which sounded much smoother.

Thanks again for your measurements!

[ivica]

I have now completed the measurements and albeit not the same quality as anechoic they do give a reasonable picture of the various JBL 1,5" drivers on the VTX, M2 and 4367 WG's, on and off axis. At least the settings (HW/SW/room/settings/timing/temperature) are identical in all measures, which makes them direct comparable. The result is about 400 measurement files at 50cm and 100cm distance for 30, 60 and 90 degrees. The files are done without any smoothing and include phase. I did do 3ms, 6ms and 9ms time windows for all combinations to make sure that I got reasonable low end data with a long window but also a short window to see the high frequency with limited room intervention. I used pairs of 2450SL, 2451SL, 2451&475Nd, 2430K and 2451h (Ti, only one). 9 drivers all in all. I have long argued that the 4" drivers do sound good on these WG's and numbers seem to support that. Please bear in mind that these are raw files and would look significant "nicer" with some smoothing, as most (also JBL) manufacturers show them. It is also clear that 4" goes lower than D2 in these WG's and that 4367 provides horn load to a lower frequency that M2. M2 sure is nice off axis. Horizontal and vertical dispersion is NOT the same in the M2 as could be anticipated from looking at it. Below are some graphs. You can see measurement data (distance, time window aso) in the graphs. SW is LspCAD 6 PRO with MLS pulses at max resolution. HW computer + Focusrite SOLO V3 soundcard, Earthworks M30 mic, and an Alesis RA300 studio power amp. All walls (and ceiling) had at least 8cm thick sound padding (with egg crate surface absorbers). Measures are 2-channel, meaning that one channel measures the power amp out and second channel the mic and we only project the delta. No capacitor, only a protection resistor in series, so phase is not tuned 90 degrees as in many other measures with protection cap. Kind regards //Rob

HI Rob, Nice work. Many thanks that You have shown such work to us, Best Regards Ivica

[emilime75]

I'm going to do a measuring run on JBL M2, 4367 and VTX waveguides the next few days. I will try a few different dia's in 2450SL, and 2451 cores. I'don't have an Mg dia and not sure it will take apart my other system to get to the Be's. I will prost some findings here and if someone want the raw data just give me a shout.Kind regards//Rob

Rob, from your testing and in your opinion - how low could a 2450SL on a VTX waveguide be crossed over if in an active system? Do you think the combo would work well as a 2 way with a 2216ND?

[sebackman]

Hi emilime75,

I typically XO 2450SL om the VTX at about 1Khz LR24. Somewhere between 950 to 1200Hz dependent on woofer. A 10 or a 12" can go higher which may prove beneficial in some setups. In the Franken HiFi Array's we do 1050Hz above PRO1400 with LR24 both ways. 0,271ms delay on woofer and 135 degrees phase on driver.

On the 2216 I would go for 1kHz and I think that would be an excellent combo. The 2216 can go up there and is probably one of the few 15" in the world that can, while offering good bass and mid range. You can't go wrong with that combo.

In my new 4367 clone I XO 2451SL at 750Hz because the horn can do it (much wider) over 226Nd-1 and that is very promising so far.

Go for it!

//Rob

[emilime75]

Hi emilime75,I typically XO 2450SL om the VTX at about 1Khz LR24. Somewhere between 950 to 1200Hz dependent on woofer. A 10 or a 12" can go higher which may prove beneficial in some setups. In the Franken HiFi Array's we do 1050Hz above PRO1400 with LR24 both ways. 0,271ms delay on woofer and 135 degrees phase on driver. On the 2216 I would go for 1kHz and I think that would be an excellent combo. The 2216 can go up there and is probably one of the few 15" in the world that can, while offering good bass and mid range. You can't go wrong with that combo.In my new 4367 clone I XO 2451SL at 750Hz because the horn can do it (much wider) over 226Nd-1 and that is very promising so far.Go for it!//Rob

Thank you for the reply, Rob. Guess I now have a big decision to make, but I should probably start a separate thread and not derail this one.