not quite...

these measurements (rta as you correctly mentioned) stem from three different locations of which only one uses a line array - also, most subwoofer arrays are designed in a way that they become rather directional at whatever frequency; of course the lower one goes, the more difficult it gets - the idea that one hears just the output of a single directive horn in a specific position when using a line array is flawed.
nothing else going on here either and no way on earth someone is cutting the lows this much: on the contrary, most system these days get aligned with a 6-10dB bass bump (unfortunately)!

please note that as mentioned previously, these screenshots are no measurements of the systems with pink noise on but what the actual response of the music looks like; measurement responses of the systems with pink noise would indeed look way more flat, depending on distance and alignment. nevertheless, roll off starts almost always clearly below 10kHz, certainly for music reproduction: i usually go for a curve that is close to the old b&k curve (or the whatever the headliner's tech wants me to dial in).

for comparison, here's a screenshot from a measurement (fft in this case) of a system which i re-installed last summer, in a venue that mostly houses classical music (and for which the system doesn't get used at all) but also modern music and jazz which was taken into consideration when designing, positioning and aligning the system (which is fairly large/uses a multitude of speakers, both arrays and point source speakers, fills, delay lines, subs etc.)

lol - thx but i guess you're hitting the wrong person! afaik i'm one of the very few folks around this forum who does actually carry (or rents) a pa even on acoustic gigs (if i haven't been working in the venue before which is highly likely if it's in europe though) exactly for this purpose: to shoot the room (and to sample the room for later use of my sony reverb) - besides, i'm often using a multi-mic rig for measuring...

Did you really leave the system like that? Were they happy with it?

I hope I'm not coming across as a jerk, I'm just baffled by seeing that curve. I design and tune installed systems and would never ever leave a system looking/sounding like that. Yes, sometimes clients want 6db of sub tilt below 100hz. But to not correct the rest of the range, especially the low-mid summation build-up and at least some of the air absorption (which is that sharp roll-off at 14k you have)... I can't imagine that system is anywhere near sounding its best.

The correlation trace is abysmal too, which makes me think either the measurement is not being done properly, or is way off-axis of the speakers, or the space is incredibly reverberant, or something in the system is straight-up broken. Given the correlation trace, you can't rely on any part of the measurement being accurate other than the 150hz region. Where is the signal in time, in the impulse measurement up top? It should appear as a single point in time, plus or minus a couple distinct later reflections. Instead there is a cacophony of noise. It looks like SMAART probably couldn't even find the correct delay value.

As for the frequency response, like I said, line arrays or other multi-element systems often start out looking something like this. But they cannot be left in that state. It would sound horribly muddy and exacerbate any room build-up. You said "no way on earth someone is cutting the lows this much" but I promise you it happens every day on professional systems. Such cuts are almost always built in to multi-element presets in system processors. Processors are designed to be used to cut that much of the lows in multi-element installations.

Have a look -- here is the default EQ curve that Meyer uses for a 4-box Mina array at 100ft distance with 100% atmospheric correction (which is the 16Khz bump *only*). This is what they know will bring 4 boxes flat in an anechoic environment - and each individual box starts already flat in the nearfield by itself. The curve needs to get even more extreme if you add above 4 boxes, and also is not accounting for any kind of room response yet. EQ curves bigger than this are being used every day on systems everywhere.

i don't recall when i took this pic during a two-day period of aligning the system so i have no idea what was going at this very moment, which sub-system was already frequency or time aligned, switched on or not, correctly positioned or not (they are using three different stage sizes for which sidefills need to get re-positioned) etc.

the only reason i posted these pics was to illustrate (to those who probaly never get use a measurement mic but might know that they essentially measure flat, whatever that means...) that there are massive differences what a mic can 'hear' and how the graphs can look depending on the distance of the mic to the source...

...or short: to underline dseetoo's post 108.




p.s. yes, the venue is fairly reverberant - here's a link to another thread which has some pics of the venue (sorry, 'concert hall'...); i'm sure you understand i cannot share detailed information on the alignment though...

reinstall before restart

My consideration is probably dumb, but I would think that approaching to the source with an omni may, in addition to a less HF loss, produce a different behavior also depending on the proximity to a certain part of the instrument.
Is it wrong to say that, if I have a flat omni mic and want to record a dark sounding piano I can achieve some "brilliance" placing the mic closer to the high notes more than the bass?

Those designs will be compromised for weight. I worked on a NASA Launch tower, we had to fight over weight vs requirements. They backed on the requirements to satisfy weight of the launch tower. I can just imagine the weight limitation for stuff on mars.

Elegent - the DPA site says:
a 4006 Omni Mic, MMA-A Digital Audio Interface and MMP-G Modular Active Cable,

Looks pretty lightweight...as far as interfaces go !

https://youtu.be/6WuHIaWIDCw

Yes, you're right in that you'd be effectively 'mixing via placement'...so discriminating via mic location towards those sounds you want to emphasize vs those you want to mask,,,perhaps ?

In your piano example, it's possible for example that the bass content remains relatively constant (let's say under the lid) but that you'd increase brightness by bringing it closer to treble strings, thus altering the ratio of darker to lighter tones ? The darker tones might remain constant, but you'd be 'swamping/saturating' them with the 'brilliant' tones ?

In my example, I was thinking more of a whole orchestra as the sound source...in that case, there are limits on how close you can get while still retaining balance...and "balance" in this context is more about instrument-group representation, rather than high vs low frequencies per se ?

This is exactly what I meant. One thing is the source "as a whole", in which probably the distance affects HF response by moving back and forth. I was asking about a more "spot" use of omnis which may also help to "tune" the recorded sound not only in terms of louder or softer ( which gain level can adjust) but also as brighter or darker. Still a possible use of flat mics...