KM2

[Anti K]

Found a MID (possible candidate in term of needed features incl. match into cabinet)

Am I right (?) : Low(s) do in their cabinet 16,2 degrees phase shift at 300Hz by math (if it does more, the cycles repeats after 3,3ms and matters what is going on around zero).
Adding one 1st order LP at 300Hz causes 1/4 cycle delay.
Maybe adding a coil, adjusts resistance as well and 'bends' the left grapf shape even closer to the right one...
Shortly, result phase shift of low @300Hz is 286,2 deg.

Certain MID in certain tiny cabinet, with high Qms, very low Qts, very high sensi, I got (by adjusting cabinet) @ 300Hz = 286,2 deg

Both in result 286,2 @ 300Hz.
In theory, adding now 24LR LP and HP slopes (360 deg) they should be at 300Hz exactly in-phase? In theory.
Anorther thing is of cause
- fine tuning in reality by DSP (never get box inner volume and air resistant as precise)
- adjusting phase between HF and MID would be more challenge.

Thanks to JBL. Long time ago in past was thinking: in MID area in theory can go with cabinet as tiny, as it's physically not possible to build!? Now, especially models 2169 (or 2250 as well) show, it works actually in reality and how to do that...

[Anti K]

Choosed 2261H as MID.
Brand new buyable, in production. Used in Vertecs (power handle should be out of question)

Qms 4, MMS 49gram (1/3 of 2216Nd), strong 2x3'' VC = should move fast.
Heavily rigid alum.alloy basket.

(have experience with PHL 3430, on paper just like everything OK but cannot handle power , one BMS looked VERY interesting, on paper ...
... so let it be JBL , a savage. Period)

Turns out, the most informative area would be surprisingly tiny,
the rest of baffle is just 'supportive'

[Anti K]

Choosed 2261H as MID.

Had my doupts, but suddenly remind a lightig moment.

I'm engineer and producer. Last one means responsibility.
Changed some items inside my production some time ago - a Japanese ones to Austria ones. Last ones were same good on paper.

After a year of working the Austria items start little bit fail, finally - all of them. Nightmare warranty journey...
Despite the Japanese ones didn't fail NO ONE. Despite I used them even before and 10+ times more qty. NO ONE.
They firstly came out with certain tech, have longest experience (and certainly best brains as they came out first with THIS tech).
Simple as that.
This is not the only exaple i have...

I'm looking this DiffDrive drivers' basket, it reminds me military equipment. The ugly straight, therefore crazy rigid construction, compared someone's fancy curves, painted and patterned baskets.


Who wins battle on paper, who actually ?

[jmpsmash]

JBL drivers are designed to be handled very rough. Those baskets, when not being used in a speaker, can probably take the place of a car jack stand when you need to change the car tire.

Having said that, one of my 2216ND-1 arrived DOA. The replacement did work and has been playing well and taken a lot of abuse since.

[Earl K]

Choosed 2261H as MID.
Brand new buyable, in production. Used in Vertecs (power handle should be out of question)

Qms 4, MMS 49gram (1/3 of 2216Nd), strong 2x3'' VC = should move fast.
Heavily rigid alum.alloy basket.

(have experience with PHL 3430, on paper just like everything OK but cannot handle power , one BMS looked VERY interesting, on paper ...
... so let it be JBL , a savage. Period)

Turns out, the most informative area would be surprisingly tiny,
the rest of baffle is just 'supportive'

If you buy new JBL products make sure you have a clear avenue for return or replacement ( in case of defective product ).

JBL's Quality Control has been going down-hill for quite a while now. Given your location you don't want to be caught holding expensive "boat-anchors" .

Here's a screen grab shot of a 2261h for sale ( from Reconing Speakers > in Florida ).



Notice the 2 very visible casting flaws ( cracks ) in the basket's rim ( as well as the annoyingly off-center sticky label ).

It's hard to believe that this retail company choose this example to post pictures of ( OTOH, maybe it's a good indication of their own lax attitude towards QC issues > IOW consider a different reseller ).

[Riley Casey]

Not sure what constitutes "quite a while now" but I've had seventy 2261s in portable service for almost twenty years without problems.

If you buy new JBL products make sure you have a clear avenue for return or replacement ( in case of defective product ).

JBL's Quality Control has been going down-hill for quite a while now. ... .

[Ian Mackenzie]

You will need to assess a close box yourself.

But this is what l would do.

Use the implementation from the M2 because it works.

You need higher sensitivity and more LF power so do a 4435 implementation.

4 x 2216nd is going to give you more kick if you blend the woofers correctly by running them up to 290 hertz. This can be done with an active crossover by cascading the 2nd woofer via the output of the main woofer filter with an additional low pass @ 290 hertz of 12 dB per octave and equalising the main woofer for a flat response with the horn. This is referred to as tri amping. When applied to the DD67000 is light years better according to Greg. So it should work with the 2216nd.

So you have two 2216nd woofers kicking really hard with their negative temperature coefficient Vic wire. The dual reflex loading with front ports will be significantly more dynamic with lower distortion as the cone displacement is 1/4 of a single 2216nd. The dual 2216nd will give you an additional +6 power handling and a +3 increase in sensitivity. That all adds up to a cleaner more effortless sounding system.

I think you will have a more difficult challenge blending the 18 inch sub to a sealed 2216 in practice.

The wider baffle is going to give you improved reflected acoustic output below 150 hertz into the room which you will associate with a bigger sound. Heck l might even try this myself.

[pos]

When applied to the DD67000 is light years better according to Greg.

Did Greg specifically mentioned replacing the 6dB/oct passive filter with a 12dB/oct active one, one octave above the original one?
I would love to read about this if you have a link.

[Ian Mackenzie]

Yes, not published on the LHS.

[pos]

Now you have said too much Ian, I am genuinely interested
Was it a private discussion? No trace to be read/heard anywhere?

[Anti K]

IOW consider a different reseller

can You advise some in EU

[Earl K]

can You advise some in EU

Ask Guido at ( click the pic for a link );



See if he can get those particular JBL parts you're after.

If he can, ask if he will open the boxes and test the components first ( to make sure they are up to spec ) before sending them to you .

Make sure you understand his return policy for damaged goods.

( Honestly, I have no idea if he can or will obtain the parts you seek ).



Guido's a longtime member here at LHF ( though, he no longer posts here )

[macaroonie]

Guido is in Germany.

[Ian Mackenzie]

---End Quote---

- I do NOT use (I cannot if think a bit) M2 Lens in this project and do NOT use D2430K as well: how the M2 implementation could work?
- I You had 4350 boxes, did You screw in there 4435? And why. I see DD66000 cabinets can be executed as modern 4350. _I prefer if MF+HF are vertically aligned._ Supposedly not entirely stupid step.
- I talk about 2261 (not 2216) assemble in small sealed box as MID. Play down to 300Hz. Lower from there would be 2 x 2216 (think about even 2 x 2265 - not as low, lighter cones as well)

I have only one question: 12inch 2261H has ca3X lighter cone than 2216Nd, and it can be assembled vertically below horn.
Do You /everyone/ say that 2216Nd with its 140gram MMS - placed off-axis from HF - is wiser than fast MID exact below HF?

3 in 1.
- 2261 is lighter (59gram vs 140 gram)
- Vertically aligned with horn.
- MID not have to mess up with lows, below 300Hz

But *NO.*
*Why ?*

You seem to be hung up on cone assembly mass.

The mass of the cone assembly is only one of a dozen or more factors considered then designing a driver for a particular application.

Those 10 inch not 12 inch 2261H drivers used in pairs in jbls VTX V 20 are useful down to 80 hertz and -10 dB at 60 hertz in that design but of course you knew that.

https://jblpro.com/en-US/site_elements/v20-spec-sheet

The application notes for LF reinforcement are here.

https://jblpro.com/en-US/site_elemen...es-vtx-v20-s25


If you are interested in the 2261H buy a pair and evaluate them after determining a suitable design from the TL parameters. That is a good place to start. Only you can assess the suitability of the 2261H for your project.


As Robert pointed out in an earlier post you seem more interested in going down your own road (rabbit hole) than listening to recommendations from experienced members here.

Using these forums to sound out your strategy is at best risky as only you can make the relevant decisions, bite the bullet and then do the real work which can take quite a while.

It will go but as they say it won’t lick itself. You will spent quite a while getting it to sound listenable.

No one is suggesting your project will not be an interesting experiment but without clear viable design goals and a disciplined approach to implementation a lot could go wrong and it does. I recommend you read Drew’s Clues in the Library which carefully describes a similar system to what you might have in mind by a highly experienced Jbl employee.

Such large format systems require scale up.

This means everything including the venue and the listener distance like at least 5 -10 metres and preferably 10-15 metres. The acoustic power inside a solid structure without due attention to absorption or large bass traps can reach a point where the structure rings continuously according the reverberation time at specific frequencies. Bowel evacuation follows.

If that is what you have in mind JBL manufactures turn key solutions for clubs using the drivers you have mentioned. Would it make sense to consider a proven JBL engineered pro solution than spend time evaluating a myriad of options? Sometimes it pays to listen.

I wish you all the best with your project.

[Anti K]

You seem to be hung up on cone assembly mass.

The mass of the cone assembly is only one of a dozen or more factors considered then designing a driver for a particular application.

Those 10 inch not 12 inch 2261H drivers used in pairs in jbls VTX V 20 are useful down to 80 hertz and -10 dB at 60 hertz in that design but of course you knew that.

https://jblpro.com/en-US/site_elements/v20-spec-sheet

The application notes for LF reinforcement are here.

https://jblpro.com/en-US/site_elemen...es-vtx-v20-s25


If you are interested in the 2261H buy a pair and evaluate them after determining a suitable design from the TL parameters. That is a good place to start. Only you can assess the suitability of the 2261H for your project.


As Robert pointed out in an earlier post you seem more interested in going down your own road (rabbit hole) than listening to recommendations from experienced members here.

Using these forums to sound out your strategy is at best risky as only you can make the relevant decisions, bite the bullet and then do the real work which can take quite a while.

It will go but as they say it won’t lick itself. You will spent quite a while getting it to sound listenable.

No one is suggesting your project will not be an interesting experiment but without clear viable design goals and a disciplined approach to implementation a lot could go wrong and it does. I recommend you read Drew’s Clues in the Library which carefully describes a similar system to what you might have in mind by a highly experienced Jbl employee.

Such large format systems require scale up.

This means everything including the venue and the listener distance like at least 5 -10 metres and preferably 10-15 metres. The acoustic power inside a solid structure without due attention to absorption or large bass traps can reach a point where the structure rings continuously according the reverberation time at specific frequencies. Bowel evacuation follows.

If that is what you have in mind JBL manufactures turn key solutions for clubs using the drivers you have mentioned. Would it make sense to consider a proven JBL engineered pro solution than spend time evaluating a myriad of options? Sometimes it pays to listen.

I wish you all the best with your project.

Thanks, Ian !