I have a pair of Eminence Kappalite 3012HO 12" drivers that I wanted to build some compact 2-way monitors (doubling as small PA tops) with. For the CD and WG combo I chose 16 ohm B&C DE250s and Eminence WG10s.
Crossover will be passive, but may use a dual channel plate amp with built in dsp down the road. For now I want to keep it simple and basic.
The question is what xover point and cabinet design would you prefer to use based on LF driver performance data? I would definitely choose tighter / cleaner low end response over output capability.
Anyone have experience with this Eminence driver? It looks and sounds nice from the little bit of listening tests I've done so far in 1.5 cu ft sealed test cabs. I was leaning towards maybe some slight LF driver WG loading to increase lower mid projection outdoors and to align acoustic planes of both drivers for easier xover.
Crossover will be passive, but may use a dual channel plate amp with built in dsp down the road. For now I want to keep it simple and basic.
The question is what xover point and cabinet design would you prefer to use based on LF driver performance data? I would definitely choose tighter / cleaner low end response over output capability.
Anyone have experience with this Eminence driver? It looks and sounds nice from the little bit of listening tests I've done so far in 1.5 cu ft sealed test cabs. I was leaning towards maybe some slight LF driver WG loading to increase lower mid projection outdoors and to align acoustic planes of both drivers for easier xover.
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It also depends on what the waveguide is doing. Is it suitable for a 12" woofer?
Here I've drawn a 90 degree waveguide and to the right of it is a 60 degree waveguide that holds to the same frequency. The point is that it will take some measurements to know the answer to your questions.
Here I've drawn a 90 degree waveguide and to the right of it is a 60 degree waveguide that holds to the same frequency. The point is that it will take some measurements to know the answer to your questions.
Thanks for the reply. Its about a 70 x 60 WG according to online specs. It will load down to about 1k but I'd consider it a 1.4k and thats about where I considered crossing it depending on how the DE250 could cope with that low of an xover. I have my doubts. Thats why I was putting out the inquiry to diyaudio folks.
Thanks for the verification. Thats about what my quick math was telling me. Once my lap top is up and running again and the cabs are built, I can start measuring some stuff, specifically the CD + WG combo to see if the DE250 will tolerate that xover. I have my doubts... we'll see.
The big question I have now is whether a slight WG in front of the KL3012HO is feasible or a waste of time. It would likely just be a slight conical profile shape WG. Has anyone ever figured out a predictable way to calculate such an animal? I don't want to waste designing this into the cab if it won't do anything other than add some weight and actually hurt performance. I just want a little more lower mid projection from these things so they don't sound thin at a slight outdoor distance.
What are you trying to do, hold directivity to a lower frequency? A small lip isn't likely to do a whole lot.
I was looking for just a little bit of low mid emphasis to overcome losses placing the cabs higher up in a 4pi location ie on speaker stands. Sure, I could just add some EQ, but there are other reasons why I wanted to design it into the cab itself, one od which is acoustical efficiency.
You're probably right in that a shallow WG the width of the cab won't do much, but I'm not looking for several dB of gain, just maybe a mild bump of few dB from around 150 - 300 Hz and the added benefit of having the acoustic centers of both drivers closer to each other for better integration and easier xover design.
You're probably right in that a shallow WG the width of the cab won't do much, but I'm not looking for several dB of gain, just maybe a mild bump of few dB from around 150 - 300 Hz and the added benefit of having the acoustic centers of both drivers closer to each other for better integration and easier xover design.
Think Altec A7 cab front horn in size to start with as it's a many decades long well proven/documented design, which as you can see (top plot) unloads around 150 Hz and loads to its reverse calc'd ~342 Hz roll off and either adjust its throat to go higher and shorten it for less gain, or of course just DSP it now that it's so relatively cheap.
Basic HR horn specs:
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That's almost like adding a 2nd LF driver in close proximity, getting the benefit of coupling gain. A tannoy style appature lens in front of the LF driver would really change the effect of loading even without the WG, but that will just screw with everything higher up too.
I don't really want to change much above 300 - 400 Hz as this will make the speaker sound boxy - not a good characteristic and reminds me of that poorly tuned ported enclosure sound of cheap PA speakers. I want tight midbass / lower mids from these speakers, which is why i picked these Eminence KL3012HOs to start with. Adding EQ would be an easy fix, but I wanted to naturally boost efficiency down in the lower mids to increase output capability in that range.
There were some older yamahas that I remember having this style of cab with the shallow LF horn loading - model S4115H. That WG was probably not very effective under 200 Hz judging by the graph provided by Yamaha. These were very popular in the early 80s with DJs... ask me how I know. Lol
I don't really want to change much above 300 - 400 Hz as this will make the speaker sound boxy - not a good characteristic and reminds me of that poorly tuned ported enclosure sound of cheap PA speakers. I want tight midbass / lower mids from these speakers, which is why i picked these Eminence KL3012HOs to start with. Adding EQ would be an easy fix, but I wanted to naturally boost efficiency down in the lower mids to increase output capability in that range.
There were some older yamahas that I remember having this style of cab with the shallow LF horn loading - model S4115H. That WG was probably not very effective under 200 Hz judging by the graph provided by Yamaha. These were very popular in the early 80s with DJs... ask me how I know. Lol
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I also realized something interesting about the KL3012HO impedance response - that wiggle in the lower midrange is caused by basket resonances and goes away when the driver is clamped into the enclosure by its mounting points. I assume Eminence doesn't mount their drivers when measuring impedance. The KL3015 shows this behavior as well, so its likely a result of the driver frame resonating.
