I don't know what to say.. good dipoles+ some room reflections do have the capacity to put you right there with the right recording, I never felt that with a box speaker.. even near field. Multi mic is certainly not good. Linkwitz binaural test disc as said is fabulous in that aspect, you are really in the hall, with people caughing and whispering right next to you and the stage far away, like the real thing.. Magi/Uppsala discs are in the same veine..and you do need the room reflections to get that! What about a variable acoustics room? that would be the solution!
Regarding dipoles and loudness, you do need to tame the highs a little bit with EQ, then you can crank it up!
Regarding dipoles and loudness, you do need to tame the highs a little bit with EQ, then you can crank it up!
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Myself I prefer to have it more or less flat from 1 kHz and up, with the level increasing 1-2 dB from 1 kHz down to 100 Hz, and then a 10 dB rise in response down to 20 Hz, not far from what you have here in fact.
now I know why you need so many woofers! and the stellar room treatment too.. 🙂
Yup, its 12 dB more at 20 Hz than a flat curve. 12 dB translates to four times the displacement, which is dramatic when we talk dipoles. The required cone excursion in a dipole increases 8 times for each octave down, and then we put 12 dB (or 4 times) on top of that again....
Not a big problem since dipoles are not pressure sources. Dipoles don't trigger the standing wave modes as much as omnipoles. That being said, I have several tuned absorbers (panel absorbers and resonator tubes) to handle all the standing waves below 70 Hz, and porous absorbers (Rockwool) that are effective from 60-70 Hz. But I believe it would work well without treatment, although the room decay would be longer.
Played again last night.. The classical recordings worked well when I removed the silly EQ on the bass. So, we removed the box to take the "colour" away, but then the room comes in.. What about a cardioid instead? I can't see much logic in playing a dipole against a dead wall..😕
from SL website:
Omnidirectional is the mother of all loudspeakers. An omni can instantly illuminate the room with sound of all frequencies, like an explosion. It has the ideal spatial impulse response. It generates a fast response from the room. The dipole is a close second. The cardioid does not see half of the room and is not a contender for speed. It's Gestalt is too strong. In practice, the omni cannot dissipate instantly the airborne energy behind the cone and the structure borne energy in the cabinet, thus smearing the impulse. The dipole does not have this energy dissipation issue. All vibration energy is used to radiate sound to front and back. Illumination of narrow regions to the sides of the room occurs via reflections, thus slightly delaying the total build-up of sound in the room. In practice a dipole is the fastest of the three radiator types that have a constant power response.
from SL website:
Omnidirectional is the mother of all loudspeakers. An omni can instantly illuminate the room with sound of all frequencies, like an explosion. It has the ideal spatial impulse response. It generates a fast response from the room. The dipole is a close second. The cardioid does not see half of the room and is not a contender for speed. It's Gestalt is too strong. In practice, the omni cannot dissipate instantly the airborne energy behind the cone and the structure borne energy in the cabinet, thus smearing the impulse. The dipole does not have this energy dissipation issue. All vibration energy is used to radiate sound to front and back. Illumination of narrow regions to the sides of the room occurs via reflections, thus slightly delaying the total build-up of sound in the room. In practice a dipole is the fastest of the three radiator types that have a constant power response.
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sorry to post again but thought I would share the last one.. I reversed again the setup, back to "normal", absorbing behing listener/reflective behind speakers. Well, It took me a while to get back into it, and... I just don't like it anymore, the stage is not fully coherent, balance is brighter, and I can't listen very loud. For acoustical recording with 2 or three instruments, it's still very nice and clear but just sounds mushed for anything else. Stig Erik wins. 🙄
He now has to tell me how to transform a living room into an anechoic setup AND keeping the wife! 😀 C'mon mate!!
He now has to tell me how to transform a living room into an anechoic setup AND keeping the wife! 😀 C'mon mate!!
sure!
I think the direction given by SL is misleading. His setup is semi reverberant (standard furnishing) behind the speakers and "open" behind the listener, I believe he has 16m total length or so.. Well, "open" is NOT synonym of "dead" and gives a very different perspective on the necessary late reflections, especially on smaller rooms as this document confirms:
http://www.davidgriesinger.com/Importance of direct sound.ppt#264,2,Introduction
now I know why I had an "in your face" sound, too much (and confusing!) direct sound, and no late reverberation= no envelopment..
I think the direction given by SL is misleading. His setup is semi reverberant (standard furnishing) behind the speakers and "open" behind the listener, I believe he has 16m total length or so.. Well, "open" is NOT synonym of "dead" and gives a very different perspective on the necessary late reflections, especially on smaller rooms as this document confirms:
http://www.davidgriesinger.com/Importance of direct sound.ppt#264,2,Introduction
now I know why I had an "in your face" sound, too much (and confusing!) direct sound, and no late reverberation= no envelopment..
They "trigger" standing waves as much as omnipoles. Like omnipoles it depends where they are placed within the room. This determines how a source couples to modes.
Dipoles dont (in theory) trigger the modes if placed in the pressure zone of the mode. All modes have pressure zone near a corner, and if we place the dipole in the corner the modes are not triggered... in theory. In reality, the modes are triggered, but far less than with a monopole placed in the same location.
Not near but at a boundary. How close and at how many boundaries are dipoles commonly placed? 😉
Well, for low frequencies that really doesn't matter all too much, since the wavelengths are long. My dipole woofers are placed as close to the walls as possible to minimize the "drive" of the standing waves. Thats how dipole woofers should be placed, and not far into the room as we see much too often. I've tried that, and it doesn't work well.
I have measured omnipoles placed at the same location, and the different is big.
I have measured omnipoles placed at the same location, and the different is big.
Of course there is a differnce. The questions is "is it better"?
The best location for woofers is practically never the best location for tweeters. So it's probably more practical and rewarding to use a sub/satellite approach even with dipoles.
Yes, its better. Much smoother frequency response and cleaner decay.
You are right - woofers should be separated from the rest, since they require different placements within the room to get the best result. XO point should be around the Schröder frequency, or approx 200 Hz.
And this is exactly what I have done myself.... 🙂
You are right - woofers should be separated from the rest, since they require different placements within the room to get the best result. XO point should be around the Schröder frequency, or approx 200 Hz.
And this is exactly what I have done myself.... 🙂
I've done such measurements in four different rooms, and they all showed the same thing.
It all started with an experiment I did with a friend of mine, who as the time wanted to build the Linkwitz Orion. We tested a setup with two 10" in both bass-reflex box and a baffle, at the same location within the room. While the box measured like +/- 15 dB, the baffle (with 6 db/oct dipole compensation EQ only), measured better than +/- 3 dB. At the time I was not a fan of dipoles at all, but that experiment changed everyting for me.
Sadly, the measurements got lost in a harddrive crash.... 🙁
It all started with an experiment I did with a friend of mine, who as the time wanted to build the Linkwitz Orion. We tested a setup with two 10" in both bass-reflex box and a baffle, at the same location within the room. While the box measured like +/- 15 dB, the baffle (with 6 db/oct dipole compensation EQ only), measured better than +/- 3 dB. At the time I was not a fan of dipoles at all, but that experiment changed everyting for me.
Sadly, the measurements got lost in a harddrive crash.... 🙁