Then there is the Danley SBH series of speakers that use Paralines to implement column speakers with e.g. 120H by 20V coverage angles
http://www.danleysoundlabs.com/danley/wp-content/uploads/2015/01/SBH-20LF-Spec-sheet.pdf
http://www.danleysoundlabs.com/danley/wp-content/uploads/2015/01/SBH-20LF-Spec-sheet.pdf
Hi Nils!
I hope your daughter is ok, once you've got some time for audio
.What is sensitivity of 8 small upper-mids?..
Hi Nils!
I hope your daughter is ok, once you've got some time for audio
What is sensitivity of 8 small upper-mids?..
Yes, she is fine. Thanks.
Everytime she notices the prototype she gets excited and want to listen to music.
@bbutterfield
If you are interested in a very strong vertical directivity you should consider a line array. I tried it and used Keele's CBT shading. Please take a look at these measurements.
The bggest drawback is high costs due to the high number of channels. And the horizontal directivity is still a problem to solve (especially with multi-way). But if this doesn't bother you than it is worth a look.
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The expansion looks correct. At a narrow angle a waveguide is both longer and larger at the mouth than at a wide angle a the same frequency.
I forgot to answer this. The upper midranges are Aurasound NSW2. Their sensitivity is only 81 dB which is really bad. Since I use 8 drivers per side overall sensitivity is a bit better. I searched long for a suitable midrange with a small diameter (which is important for the concept), but there is none out there. Even the Morel MDM55 is too big. So I decided to use the NSW2.
I wish Aurasound would produce a real midrange driver with the same body as the NSW2...
I still have to tilt the horns back a bit (which is why I suggested a 60x40 horn), but yes I can completely avoid ceiling, floor and wall reflections. I may pull my backyard synergy horns which are 50x50 into the mix...smaller easier to move and test with.
In the current configuration I've taken a measurement, 200mS window, both stereo speakers, at the listening position. The graph is smoothed at 1/48 octave to average out the hash that occurs with measuring this way from reflections furniture, microphone stand etc. There is a room mode null at 90 hz and peak at 58. Impressively even midband.....
Scott
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Nulls at ~300 Hz and ~500Hz are??? 3rd and 5ths of the room null at 90 Hz???
I am curious what is the cause for this concern. I can imagine 2 reasons:
1) Off axis listening.
2) Reflections.
In the case of reflections, the highest frequencies are by far the easiest to deal with at the reflection point. Therefore, a design the reduces mid frequency reflections but fails to reduce high frequency reflections is still of great value, if that's your concern.
If you plan to listen significantly off the vertical axis, then you probably wont want loud high frequencies paired with attenuated mids. Do people really do that?
If I understand this correctly, you had both your left and right speakers playing for the measurement? Is that the reason for the dip at 6Khz? Was the mic not exactly between the speakers (off by a couple inches maybe)?
It looks impressively smooth. Thanks for sharing.
Why is that considered good? I always sit when I listen to my speakers. Why should I care what is happening above my head? Accounting for high stools, low couches, short and tall people I don't see a need for more than +/- 5 degrees.
Do people really stand and listen to their speakers for any significant length of time?
This is true, but my room is not treated well and I don't want to do this. My goal is a nearly constant directivity from low to high frequencies.
And yes, sometimes I walk around in the room and then I notice coloration caused by non-constant directivity very easily.
This prototype is the 8th of its kind. The last predecessors used a 40°x40° horn in the center. The imaging was impressive! Even 3.5 m away it sounded like 1 m in front of my face. A 3-way speaker with waveguides in comparison sounded far far away. I like this short distance perception and this exclusion of room reflections.
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+/- 5 degrees is a 10 degree window, not far off from my 15 degree window and might simply reflect a greater listening distance than I assumed
One of the things that drew me so strongly to the Synergy horn concept was the singular point of wavefront source, the mouth of the horn. With ribbons or multi-element line sources you have diverging wavefronts that sum correctly at one location, and less than correctly at every other location depending on the bandwidth of usage.
Scott
Because in a room without tremendous amounts of diffusive and absorptive treatment you're listening to the speakers and the reflections. The more uniform the spectral balance of all the of the reflections, the less objective they are according to some studies. Toole did a lot of work on this I believe.
Scott
Probably. Also remember the dimensions of my horns are such they don't have significant directivity until above ~550-600Hz.
Scott
Yes, this is both speakers playing the REW test signal. The gate time was 200mS which equates to 68.6 meters or 225 feet. So the reflections included in this plot are ones that have made multiple bounces off of the surrounding environment. (Longest room dimension of 20 feet.)
The dip could be both an off center microphone and a reflection off of the not very absorptive sofa fabric that was a few inches behind the microphone.
Keep in mind the measurement was made in a room with ZERO room treatements. No diffusion or absorption on the back wall other than an oil painting. Side walls have curtains and windows on one side and curtains (to make it a mirror image on the other.) The curtains cost $20...at a Bed Bath and Beyond clearance so the acoustic properties were not a first order concern.
Scott
But what are the properties of "balance" that are important? Certainly multiple reflections can reach the listener at approximately the same time, and create an interference pattern. Is that pattern considered "balanced"? (Consider higher order floor and ceiling reflections from a speaker radiating at the same height as the listener, for example). Are nearly simultaneous reflections any better or worse than individual reflections (once scaled for equivalent power)? Does balance refer only to the relative power levels of a few broad bands across the frequency spectrum? Ex: Low, Mid, High?
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