B&C DCX464

Any thoughts about this crossover:
Convair Custom Crossover for B&C DCX464 Co-axial PS25.50 IN STOCK (29 Jul 2020)

Convair Electronics Crossover designed for use with the DCX464 Compression Driver. Non-standard alignment used to compensate for impendace bumps on the DCX464. Slight HF EQ added to smooth out the overall response of the DCX464. This crossover is VERY specifically for the DCX464 only, and is not intended for use in other applications.

SPECIFICATION
Type: Two Way Crossover with HF attenuation and EQ
Nominal Frequency: 3100 Hz
Slope: 12dB/octave
Impedance: 16 ohms
RMS Power: 750W
Program Power: 1200W
Dimensions:134mmx106mm
 
With the wealth of information given by Convair it should be possible to reverse engineer the crossover, which I just did.
I am only a little bit unsure where the 4.7 and 3.3 caps belong,
one way seems better but the PCB pic suggests the other way round.


Anyways they acomplish a flatter FR than my design at the cost of slight substraction above crossover point, means phase tracking above crossover isn´t as good as mine.
Also they omitted HF protection, which will be absolutely okay for Hifi.


For some reason I can´t stand yellow caps, probably opened too many chinese speakers :)
 

Attachments

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Hi UR155, haha ...an IIR phase matching skill I see absolutely no sense in acquiring, :D
But seriously, very nice.

I'm left thinking the reported dip in the mid at 3.5k is entirely horn specific.
Because I see the dip at 4k on an xt1464,
and on a bunch of different frequencies with various synergy attempts.
 
Is 464 and 462 identical besides the mouth/adapter?
Thinking if the crossover would differ or not. Ill reach out to convair to see what horn they used to develop the passive crossover I linked earlier. May go with it as a start while working on a specific for my purpose.
 
So, what are people running below the DCX464? I’m planing a FLH bass horn (2x12pe32) from about 40/50-300/500 hz. Or maybe just one or two sealed 18”.
Currently waiting to see the new B&C-horn.

I’ll use the system in a home theater/dedicated listening room. Maybe with a Class A amp.
 
Bennet Prescott from B&C said somewhere, that Pro customers would always roll their own horn design for the 464 and tooling/shipping costs would be quite high, so I wouldn´t hold my breath for B&C releasing the prototype horn.
But if you promise to buy 50 :) , maybe.

Regarding the question what goes under the 464:
FLH from 40 to 300/500 Hz is quite a bandwidth, maybe impossible.
The enclosure design with widest bandwidth is closed box, so 2x 18" sounds good to me.
 
Why choose 2 X18"?
One should be enough per side IMHO

Just depends on how much SPL is wanted, huh?

One 18" will not keep up with the dcx, unless maybe the dcx is being run very low on a horn that doesn't load it that low properly.

@ oLjud,
I like a 12" between the dcx and subs.
Gives more freedom of choice in both what sub to use as well as in horn choice.
Better opportunity to get pattern control right between horn and xover to bottom.
Also allows more very clean SPL too, i think.

Doesn't have to be 12"...I've used 10"s, even trying a pair of 8"s in a synergy right now.
I just would not go straight to a sub....
Agree with UR155, FLH 40 to even 300, would be a hell of a difficult feat.
 
Over at a Facebook group (can’t remember) Mr Prescott has promised to reveal a horn at the end of the month (September). So have some faith.
He might also have showed us that horn a couple of times but always dodged my question regarding if it is the actual horn that will be for sale.
 
Maybe your both right, it is a wide frequency range for a FLH, my initial plan was 80-400 Hz, but after spending some time in Hornresp I got a nice curve (Ill attached one that goes from about 50 Hz).

But thats why I asked, to see what everyone is doing.

And as Nissep says, it promised to be shown very soon.

IMG_1545.jpg
 
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What would be a few “second place” choices for waveguides y’all would consider? If B&C does put out their new waveguide I’m assuming for most this will be the 1st place solution.

Looking for waveguides that can actually be obtained.

The Limmerhorn products are neat- thank you for the recommendation. I wonder if they will ship to the US?

Seos? Eminence h14ea? Just curious what y’all consider known goods for this driver (all experiences appreciated, size doesn’t matter for my personal application, they will be stacked on the low/mid driver on top of the enclosure).

Thank you in advance!