Didn't think of trying that. I might get a chance to do that tomorrow, although it could be a challenge finding the exact same microphone position to give results consistent with the previous measurements. (As well as a few objects having been moved around in the room since then)
Unless someone knows how to take an existing impulse response (pir) file in ARTA and apply custom low / high pass functions to it ? I haven't seen any built in function to do this...
Can your software generate ETC curves from the impulse responses so they can be compared directly to our results ? Trying to interpret an impulse response directly by eye for this type of information is challenging to say the least, as the apparent amplitude of the pulse will be heavily skewed towards high frequencies.
I've seen a couple of really good threads elsewhere on this forum showing measurements and discussion of lots of different wave-guides, both custom made and off the shelf. I had a quick look at my subscribed threads list but couldn't find them, so I must have unsubscribed from them
(This was before I knew you could turn email notifications off for subscribed threads, and those threads were too busy for me to keep getting emails from...)A bit of a search should turn them up.
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Consider this configuration, but move the speakers much closer together. After that, figure-out how close or far away from the speakers you prefer as a listening distance.
I agree but I suppose that for most critics of low directivity approach clarity is more about resolution understood as clear and precise reproduction of small details as those critics criticise low directivity speakers for loss of some small details
I understand spaciousness as an impression of a sound space of certain size and specific acoustic properties and of a certain extension (certain body) of a sound source in this space (ASW) and at the same time impression of clear separation of the sources and of the space between them, perhaps it is the classic understanding, in this connection check out the collection of definitions in Markus' post (after Dr Wittek's dissertation):
http://www.diyaudio.com/forums/multi-way/121385-loudspeakers-room-system-70.html#post2120381
Apart from that there seem to be VERY different opinions about what is the REALISM of a music reproduction.
I believe realism can be only understood in terms of recognition factor - sound reproduction is more realistic when it sounds more like real thing
Can it be understood in any other way at all?
And from perspective of realism understood in terms of recognition factor spaciousness as ASW and as an impression of space of certain size and specific acoustic properties seems to be very important factor, perhaps more important than clarity understood in terms of precise reproduction of low level details
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Then isn't a bit greater directivity a good thing? I mean, if I interpret your posts correctly, you advocate to minimize very early reflections (VER).
Tom,
It's good advice not to forget that most research is done by people who are from within or sponsored by the industry. But of course that doesn't mean it isn't useful: just be careful not to only read the (sometimes conventient) conclusions but also inspect the data very carefully.
Regarding your recordings, I loved the fireworks. It sounded good on my speakers, but a little dull. When I listened to it on my headphones at a credible sound level, I just laughed out loud. It sounded amazingly real! The Harley sounds nice and very palpable too, on both my headphones and my speakers, but I couldn't make much of the trains.
Most 90 degree horns have about 100 degree coverage. Do you think the Nathan has too much directivity?
Replying to myself...I decided to check the RT60 from the same impulse measurements I derived the ETC curves from, and the result is below. It's not surprising the room sounds a little bit bright and live when the RT60 climbs quite a bit above 1Khz to just over 0.4s.
So despite mostly well controlled early reflections (apart from the right side-wall) the overall reverberation time is still quite high at high frequencies for such a small room. Could use a bit more absorption in the room to get it down to 0.3s I think...
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Yes, I would want 100°-110°@-3dB (not the common -6dB) for a toe-out like this. Basically the "ideal" for a speaker that utilizes lateral reflections is two broadband lobes, one towards the listening position and one towards the ipsilateral wall. Basically the MGC-1 "done right". Don't know how to achieve this.
I always think the Genelec stuff looks like it should work well. Smooth waveguides over direct radiators. Looks about 120 degrees wide. Should hide the cabinet edges, as Simon suggests.
I've done a lot of treble waveguides like this (see my avatar, XA Reference Snell).
David S.
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I don't know how to generate an ETC curve. I tried the free ARTA without success. I was simply using HOLMImpulse to measure the Impulse Response at the sweet spot. I'm uploading the .WAV files if someone wants to process them.
...and then you end up head-in-a-vice Ambiophonics
It depends on the radiation pattern and how close you move the speakers together. And of course on how close the listener is to the speakers.
Here you go (30, 60, 90, 120):
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Yes, I'm keeping the speakers toed out for the time being and experimenting with bringing them closer to one another. A wider room would've worked better
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Yes, I'm keeping the speakers toed out for the time being and experimenting with bringing them closer to one another. A wider room would've worked better
You can always try re-orienting them in the room.
Read the Keele papers on CD flares and you will see that you can set them at any radiation angle you want. Basically a conical flare with appropriate end flaring to prevent midrange narrowing. If you make them much wider than 120 degrees then you are pretty much back to a flat baffle.
David S.
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