Compact PA - in a car handled by a single man.

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and you don't need subs, according tot the specs.


Those are awesome 2 way full range speakers using a 15" and a 1.4" Titanium Compression Driver, 4.0" v.c, giving up output above 10k. These specs are no indication for real world use / output power.

PM90? Please support a link.

Yes I agree specs on all speakers are misleading as they just give the output in the most sensitive (mid) range. The bass is usually less efficient and excursion limited.

All speakers are to a degree a compromise. If you consider the PM90 that has given up bass capability (always needs subs), is very expensive and uses a coaxial compression driver that has some issues (see axi2050 presentations at Salford acoustics conference). I guess you could use an axi2050 in the PM90 at even greater cost 😉
 
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After playing around in Hornresp, I am ready to draw my own design inspired by the Teeny Tiny subwoofer. Nothing special, just constant cross-section vent with some bracing, since it will be made from 15 mm plywood. And all 90 deg cuts. Nothing to write home about, just a standard bass reflex cab, but with small footprint for easier transport, it will be most probably slightly larger than the TT, but still small enough. If successfully built, I will of course share the plans.
 
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I got my hands on a pair of aluminium H6000 horns by RCF and here is some quick measurement with 8PE21 I have for another project. It is bare driver and bare driver with horn. It makes me wonder if, with a dedicated midrange driver by RCF or BC and a matching 1" horn would make a very compact "top" for the subs, sort of a split RCF 4PRO 6001.
 

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The thing about that idea is that the 8"/H6000 combo can only be used above about 400Hz.

Your sub's will not necessarily sound very good played up that high, and there will be an obvious and unsatisfying dislocation in where the sounds of things like voices are coming from. That is, it sounds odd when the low parts of a voice are coming from down on the ground and the rest of the voice coming from up in the air, where your mid-high's should be.

So, you would still need a decent low mid section to go with the H6000+ HF, making a bigger and heavier top cabinet.

IMO, for the size of space you're looking at working in, a decent 12" 2 way should be perfectly acceptable - for commercial boxes, anything from the Yamaha DSR112 on up, or ideally anything with a larger HF to allow a slightly lower crossover, taking some of the load off the 12". In RCF's ranges, that could be NX32, HD32 or ART732 depending on budget/availability/preference for looks and cabinet type.

If DIY'ing your tops, again, look at using at least a 1.4" HF, crossed as low as it can go without sounding harsh. The RCF cab's I mentioned above all seem to be using the ND840 which is available off the shelf and not too expensive, with a horn roughly the same size as their HF96 or HF94.
Chris G's 2x10's are one good way of doing it - though I suspect you'd get good enough results with a single 12" and save a little on cost too.

HTH,
David
 
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Thanks for your input, David. The H6000 horns will end up in my home system or in some compact 3way with the intended RCF mid drivers. I have the band from 140 to 500 Hz covered by large 15" front horns now. Maybe the H6000 could work well with some super-planar 1x12 kick bins for reducing the size - but at home, it is not too important since it is not being transported anywhere.

12" + 2" (or 1.4") is the combination I will most probably settle upon. I am following our local used market and time from time, suitable boxes appear for sale, both factory and DIY.

By the way, do you know which HF horn is used in the 4Pro6001A? According to this plan (4pro RCF) it is HF94 crossed over at 1500 Hz.
 
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With my limited coaxial driver experience, I could not hear any modulation, but that was at indoor (loud) listening volumes. At full power/xmax, it may be a different story. By the way, the first coaxials I heard long time ago were Tannoy 8" DC studio monitor. I really liked these for normal listening volumes. And I used Eminence Beta12CX for a long time as my main workshop speakers.

One thing I do not like is, that the coaxial drivers with passive crossover are not time aligned. And I guess that in 99% of the passive PA tops, they are not aligned as well. It looks as the new RCF biamped active boxes with DSP are actually time aligned, which is a big plus for me.
 
Overview

Seems OK, as the review states it achieves good dispersion characteristics in the most critical range. But I would worry about the cone movement modulating the compression driver output. Personally I would add another driver for the 120 - 300 Hz range and run the coax in a small box.

For high-power applications, I'd agree.

For the situation we're in here, the midbass cone isn't going to be moving much anyway - it'll be highpassed around 100Hz.

IMO, a 3-way system (1.4" HF, 12" MF, 15-18" LF) will do fine here. If anything, you could probably get away with a 10" midbass.

Chris
 
A better setup of the speakers would give a louder and cleaner sound as the setup in picture 1 is a comb filtering disaster.

Better not mix speakers putting out the same frequencies and never put top speakers (mids/highs) in the horizontal plane when they put out the same signal. The 2 bullet tweeters top box in pic 5 should never have been build.
I would leave the top boxes at home, put the speakers a bit higher, point them a bit down and put the upper speakers upside down so the horns (high frequencies) are as close as they can be.
If you play stereo; rotate the lower speakers inwards and the upper ones only a little bit. This will give the least comb filtering and the best stereo experience.

All subs should be together at a wall or be at least 5 meter (more = better) away from walls.


For a new system I would go with top speakers with multiple 6.5" or 8" drivers, as they will have better off axis response and more detailed mids. 2x8" with 2x200w will outperform a 12" with 800w in output.

A while back I was looking at 4x 6fe200 (€37) in 16Ohm; these can live in a tiny sealed box and make a 100 dB/W 4 ohm speaker which can be fed a kW of program power. Which would make 130dB minus power compression. But as the power is spread over 4 voicecoils this loss will be less then with 1 or 2 driver(s).
You can cross these higher to a tweeter then bigger drivers, so you have more choice and less cost (and weight) for the tweeter. A 1" tweeter will also have better performance above 10kHz.
Add subwoofers to your liking and cross them <150Hz.

Interesting, I am currently putting together a test with an EV XLC waveguide and 6FE200, ditched the original Eminence speakers and found these to fit exactly on them, need to make spacers so the surround doesn't hit the baffle surface.
High end will be a BMS 4540 on a JBL 2370A horn.
If this is all being done I will look into the low end, probably a 15"
 
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I came upon an interesting coaxial speaker - the Beyma 12XA30/Nd. There are some in 40x40x35cm boxes with passive crossover for sale locally for ca 360 Eur / 400 USD a pair. These should be capable of around 126 dB peak program (700 W amp) when used with subwoofers. The woofer and driver use one Nd magnet, so it is relatively light. These boxes seem almost perfect for my applicaton with ca 80 deg specified dispersion. Is there any reason these would not work? The drivers themselves look really nice, maybe adding a waveguide a la Danley SH80 would make these even better.
 
I came upon an interesting coaxial speaker - the Beyma 12XA30/Nd.

for that price, you's be nuts not to try them.

I almost bought a pair myself (raw) before I got my KF394's. The specs are impressive, and you can even get Be diaphrams for them, if you want.

What stopped me was that,. IMO one 12" per side just doesn't cut it for rock vocals, unless you're in a pretty small club. The low mods don't seem to carry.
I used to use Tannoy T300's, which are fabulous speakers, but always had that issue. I'm being picky, but even two 10's per side (as I have now) makes a noticeable difference at, say, 50 feet. I thought about building 2x10" or 2x12" boxes to go under these coaxials, but that seemed cumbersome. Another crossover, another amp, more weight....

Even if you could figure out how to mount them like Danley does (I assume you mean the SM80) you won't overcome this. (According to reports from several respected FOH guys who have used them.) And FWIW, I believe those are sealed boxes, so there's even less low-mid output.) - But if you're after a more "polite" sound, (Country, jazz, folk) or will mostly play in small spaces, then definitely grab those Beymas. I'd love to get your feedback on them.

- And if you actually made a successful copy of the SM80, that would really be interesting.

Last thought: If you do go this way, consider using an active crossover, like Maybe a Driverack, and another amp. You can get a few more dB out of the coaxials this way, and better sound at the same time.
 
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Yes, SM80, of course:) Active will be an option for sure at a later stage. These would be most of the time a home/garden party PA for reproduced music and sometimes pub/small club PA for a metal/punk band - we played gigs like this with all sorts of strange homemade PAs (not ours) and we did fine. These should be far above that both in quality and SPL. Thanks for the feedback!
 
Yes, SM80, of course:) Active will be an option for sure at a later stage. These would be most of the time a home/garden party PA for reproduced music and sometimes pub/small club PA for a metal/punk band

For this, the coaxials would be perfect. - Not just because of the short distance, but because both punk & metal vocals rely more on upper mid excitement than low mid fullness. (I assume you use real guitar amps, so no worries re a full guitar sound.)

Also, the small horns of a coaxial should theoretically be a little sweeter up close.

Go for it! - And please report back, as I'm srtill considering these drivers for an alternate "small room" setup.
 
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The woofer looks very amenable to horn loading (low Qes) if your looking to make something like the SM80. The recommended crossover point seems to be 1.8 kHz


Good to know that low Qes is important for horn loading, (thx!) as I'm still working out my new subwoofer build.

- But note that, again, it looks to me like the SM80 is a sealed design. It pretty much HAS to be, in order for the front openings to properly guide the LF.

I wonder if Danley created those openings using some kind of math, or physics logic, or are they just spaced openings based more on aesthetics, or physical convenience?
I also wonder how well they work at just above the boxes HPF? They aren't very deep, & I've never seen a polar response chart.
 
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Seems like there are multiple SM80's I was referring to this one, the SM80f:
SM80F | Danley Sound Labs, Inc.

It has a short horn at the front which if you look at the datasheet is giving a significant sensitivity boost 150Hz - 1khz (raw HF response). Porting the coax should work just fine, plenty of subwoofers have a front horn and a ported rear chamber. You would tune the ports just below where the front horn stops working to extend maximum output power down in frequency, positioning of the ports will not be critical and this will be below the frequency where the speaker has directivity.