OpenBaffle with MarkAudio drivers

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Hi there,

Currently I have an OpenBaffle system in WAW arangement with DSP corrected frequency response.
The used driver is an Alpair 5.3, crossed actively at 200Hz, and a KEF sub is working downsters.

I am really satisfied with the sound this system produces: Very clean sounds and good imaging, really good dynamics... The singer highly seems to be in the room.
My only problem is, that the 200Hz crossover frequency is a bit too high for the sub and too low for these drivers. It would be much better to lower the frequency to 150Hz, or further below.

My question is:
Which MarkAudio driver would be the best choice to replace the current one? Paper or alu cone?

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The cone material is less important as far as LF crossover frequency goes than size. Strictly speaking, things start becoming more obviously directional > 70Hz, so you really need a pair of subs / woofers, one for each channel, if you're crossing above that. Assuming that's not viable due to cost, space etc. considerations, then the largest driver option you can manage is really going to be your best policy to ensure power-handling / headroom stays as high as possible, especially since you're equalising it.
 
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Strictly speaking, things start becoming more obviously directional > 70Hz, so you really need a pair of subs / woofers, one for each channel if you're crossing above that.
I did not felt any drawbacks on bass directions. My main motivation for driver improvement is a huge sound level fallback at crossover point and a slight rise of distortion of the drivers.
 
In my limited experience with Markaudio, Alpair 5.3 has better HF and Alpair 10.3 has better LF. So I would suggest three possible extensions to your OB: (1) add 10.3 low-passed and/or not facing front; (2) another 5.3 push-pull or sealed; or (3) add wings and stuffing to make OB-U.

My 5.2 TLonken goes down near 40hz. The driver by itself has a natural rise around 110-120hz so your XO region should be fine if OB cancellation is controlled a bit.
 
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My main motivation for driver improvement is a huge sound level fallback at crossover point and a slight rise of distortion of the drivers.
=
...then the largest driver option you can manage is really going to be your best policy to ensure power-handling / headroom stays as high as possible, especially since you're equalising it.
;)
The main 'power region' for music (especially orchestral, which is generally the most demanding in this sense, so a good 'conservative' guideline) is < 500Hz, with a lot being concentrated in particular between 100Hz - 300Hz, so a bit of cone acreage handling this BW is no bad thing. How much will depend on your average SPL at the listening position & how much headroom you want from that, but since you say you need more output & lower HD (i.e. shift more air), then all other things being equal, a bigger driver is your friend.
 
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@Scottmoose:
I felt, that the solution is a bigger driver, which goes deeper. ;)

The main question is which driver should be the chosen one?
I know, what are the benefits of a bigger driver... but what is the price what I have to pay?
Are there any drawbacks (not mentioned the slightly falling higher frequencies) of a bigger driver?
 
Typically you'd expect a larger unit to have a little less in the way of outright HF extension, and possibly see the polars / dispersion start to narrow as frequency rises relative to a smaller unit. This does significantly depend on design though, especially the cone profile, whether it's using a direct-bonded central cap etc., so it's only a rough generalisation / guideline rather than gospel.
 
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@Scottmoose:
Yep, that's why I am interested about personal preferences about different drivers.
I read very good opinions about Alpair 12PW, but it is maybe the most expensive piece in the MarkAudio collection... But I felt some commercial smell there. :)

It would be really good to read other DIY-ers opinions/experiences on the drivers in the market.
 
The Alpair 12PW is discontinued, so unless you could find a pair still sitting on a dealer's shelf, that unit is something of a moot point. ;) The manufacturer as far as this goes is immaterial: if you want more dynamic range, all other things being equal, you need a larger driver that can shift more air. That could be an MA unit, it could be from another manufacturer, be it Fostex, SB, Lowther, Tang Band, Dayton or whoever you favour. That's just a law of physics unfortunately -you can't beat displacement. To a point, increased excursion helps, so you can get away with something a bit smaller, but the price is usually efficiency so this only gets you so far. In your case, that would mean something larger than the nominal 3in category the Alpair 5.3 resides in -how much larger & what being up to you of course. There are plenty of drivers out there to choose from.
 
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How much high frequency extension do you require? Alpair 10s or 11s (I’m no expert on the MA models) would be able to go lower, but even so, the OB roll off starts way above 100Hz unless you have BIG drivers. I doubt a slightly bigger full range will make the gap to your subwoofer, though you may be able to get there with your DSP EQ.

With OB, you may find you need at least a simple 2-way crossover between the A5.3 and a bigger driver on the baffle, plus the sub(s).

It’s certainly worth experimenting with another pair of MA drivers. Then you have the option of more speaker projects! :spin:
 
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Understood. Since you already enjoy the A5.3s, I expect you’d do well with the 10.3s/11MS/Pluvia11, plus EQ.

I REALLY like the dual Pluvia 7HDs I use, but they are in MLTL cabinets designed by @planet10 . I don’t know if two (or more) of those would work on one OB together.

The Tang Band W5-2143 may be worth considering. Some on the forum really like that driver. @Plott uses the bigger W8 version in his OBs. Plott’s Journey

I look forward to what you decide and come up with!
 
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And which one is the best bet to these drivers?
As I know, 10.3 is the oldest construction.
11MS vs Pluvia11?
They are very similarly priced.

The goal is to have a natural/open sounding speaker for mostly acoustic music.
 
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I haven’t used any of the larger ones, but as far as their frequency charts go, I’d say the order of preference would be 10.3, 11MS, Pluvia11. Scott and Dave would be able to tell you about their relative virtues/quirks.
 
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I try to leave the subjective commentary to people who are [much] better qualified than I am to make them. What I hear is very unlikely to be what anybody else hears beyond the broad / macro characteristics, and in any case, I'm not a good enough wordsmith for anything like that -fortunately or unfortunately. Probably fortunate -or maybe that's another way of saying 'I can't cope with writing purple-prose'. ;) :rofl:
 
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In my experience Markaudio's FR charts do correctly reflect how the drivers reproduced acoustic instruments -- for example 5khz dip ~ less dynamic; 9khz peak ~ overly metalic etc. The 5.2/5.3 were the ones I could enjoy without corrective measures. The10.3's 12dB plateau/peak at 7.8khz required (for me) a whopper notch filter 7-14khz. Bigger not necessarily better, on balance.
 
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Most OBs require helper bass drivers.

Unless signifcantly more levels are required the only MA driver that likely beats out the A5.3 midTop is the MAOP 5 variation.

Rather than swapping the midTweeter i would first consider improving the bottom end.

You should read thru Martin King’s p[assive OB article it has some significant clues to getting the XO right. Your 200 Hz XO is likely too low.

dave
 
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My most recent acquisition is the CHP-90. It does have a little bit of turbulence in free air during occasional on-off pops, so I wouldn't over-stress it with lots of dipole EQ. And I think it would be similar for most of the MA range.

My instinct would be to go with stereo bass for a start, and maybe try to pressurise the front wave by sharing a common baffle, or perhaps even a D'Appolito arrangement where in-phase bass is funnelled onto the wide-range driver in the middle.
 
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5.3 is 4Ohm device.
Larger Markaudio driver is only Pluvia 7 PHD (70mm) which is also 4R.
Better Fs, 78Hz vs. 95Hz of 5.3, larger MMS (3.3g vs. 1.9g), 2dB better SPL (but 87dB still in the low side for OB), 4.4mm XMax (vs. 3mm), the QES similar, QTS only a little larger than in 5.3.

IMHO it's only another "animal", I do not think so it would be "better".