Full range line array

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That's the point. Array mounted, you're not going to get 20KHz out of them. The drivers individually produce it alright, but the comb-filter effect caused by the multiple-point-sources that make up the overall line-source means that much of the HF will vanish, and that's just for starters. Using the above example, and assuming no tweeter line, & just the drivers being run FR, then from the c-to-c spacing it looks like they used in, and making a quick SWAG, they're going to run into severe combing issues from about 3KHz upward, with rapid attenuation of everything over that frequency. You can Eq out some of the overall attentuation, at the price of crippling efficiency, but the severe phase issues and the ripple in the response will remain.
 
Hi-Vi supplier

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If you are interested in purchasing HiVi drive units I suggest you speak to Ivan at IPL Acoustics, I've just put in an order for several B3N at a very competitive price, and quoted delivery cost is fantastic too.

I had quotes from madisound and IPL were cheaper once delivery and packing etc... had been factored in. Not to mention fluctuating and poor exchange rates on Credit card purchases.

Nick.
 
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Problem with a bunch of very cheap drivers is that you could end up with a lot of worthless speakers that dont work at all, and still have cost you serious money all together, no free lunch

At the moment I am thinking about a HiVi M12 woofer with a B-G NEO3 crossed low, maybe with waveguide

M12 will make pretty low bass and NEO3 is supposed to outperform XT25, and able to xo as low as 1200hz

M12 might not be very good in mids and how to make the xo, I dont know yet and it might not be a perfect match either, but what is anyway

M12 costs 95 Pound in UK at IPL, and NEO3 is 30 pound in my country (So-Fi Audio)
 
finding an inexpensive line array alternative?

One of the posters was interested in an inexpensive line array alternative. What was the dollar value interested, and where does the poster live(since choices vary by ability to purchase speakers with out of country shipping very high.)

Zarathu
 
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i see that link no longer offers pictures
so here is how one side of the line array looks like
don't let the price fool you, many speakers costing much more does not even come close to the sound (i know it does not look as good)
the sub is closed 15" car woofer 97 dB/w/m powered by 45 watts chip amp up to 120 Hz, line array works from there powerd by SE tube amp
 

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I know this is rather an old thread, but I am currently thinking abour building the K&T "twentyfive" (might be "twenty" or "sixteen" though and probably OB ;) )

Did anyone build it ? I have the K&T issue on paper and I see some interesting things there (there are measurements in the paper):

1. Yes, there is some attenuation of the highs which is contered by EQ: however, the equalized response extends well above 15 kHz. Sensitivity drops to about 85 dBSPL

2. There's a measurement showing Comb filtering between 3 and 10 kHz: even on paper, it does not look that bad (a few very narrow notches). AFAIK, human hearing masks such effects and the precedence (Haas) effect even more so.

3. I have heard far too many designs that measure great (at least in terms of frequency response- I am aware that this alone is not tale-telling !) and sound boring. I'd like to maybe see the contrary with this design.



Scottmoose said:
That's the point. Array mounted, you're not going to get 20KHz out of them. The drivers individually produce it alright, but the comb-filter effect caused by the multiple-point-sources that make up the overall line-source means that much of the HF will vanish, and that's just for starters. Using the above example, and assuming no tweeter line, & just the drivers being run FR, then from the c-to-c spacing it looks like they used in, and making a quick SWAG, they're going to run into severe combing issues from about 3KHz upward, with rapid attenuation of everything over that frequency. You can Eq out some of the overall attentuation, at the price of crippling efficiency, but the severe phase issues and the ripple in the response will remain.
 
1. Yes, 85 dB is not really impressive. One of the stregths of using many small drivers should be low power/thermal compression - but this might still hold, because the extra power is not dissipated in the drivers (but controlled by EQ)

2. The graph actually shows a strongly smoothed (probably 1/1 octave) over a "not smoothed"(looks like maybe 1/24 octave smoothing). As I said, it's not beautiful, but in the the benefits might be worth.

3. Thought I might get some feedback from people who have already built it - if any, of course.
 
I'm afraid it's my inate cynicism -a character flaw, no doubt. But I have a jaundiced view of most published response graphs, & the first thing I usually ask myself is 'what are they hiding?' No doubt, they can be useful, but you still have to be careful.

Theoretically, you should still get reasonable thermal performance from the multiple units. However, as efficiency has been drastically cut by the passive EQ, you loose the low distortion benefits of an HE system, & excursion will be higher for a given SPL (not that you need me to tell you that).

I doubt you'll find many people here (if anyone) have built them -you might have better luck on one of the German forums though.
 
I must say I am not sure I understand what you mean: are you suggesting that conventional measurements are completely irrelevant for a line array, which can still sound good in spite of them, or that line arrays sound inherently bad ?

I have checked german forums, looks like no one has actually build the original Twentifives with Visaton FRS 8Ms, but some did it with MUCH cheaper drivers (0.95 cent per driver ! the Visatons are around 10 euros each) - opinions about the sound were quite divergent though, looks lit it's "love it or leave it"

As an experiment, it might be worth trying with cheap drivers, while the costs for the 50 Visatons are comparable to buying some high quality drivers for a good 2 way design. However, the test with cheap drivers is also questionable, as you cannot extrapolate the result to some more decently performing ones such as the Visatons.
 
I am saying that you have to hear it and measure it, because it is just "different", as I experienced it now, the measurements are not comparable to your average 2-Way.
For now I gave up on (8xFostex Fe103) fullrange-line arrays, but they were great as Mids.
By the way, this software is very enlightening what to expect from fullrangers: http://www.pvconsultants.com/audio/radiation/vpr.htm
It measures exactly like that, for me.

-Micha
 
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