That description sounds like a Lowther (or similar) mounted on a wall with the rear of the cone firing into the room the other side of the wall. Would very likely need some augmentation below some frequency.Well... I was ready to mention the MAGNEPAN speakers, but they do have crossovers...
Using classic electrodynamic speakers, I wonder if an Open Baffle or Plane Baffle with multiple speakers without crossover offering satisfactory results really exists... To be honest, I don't know. Maybe ?
With a single Full-Range speaker mounted in Open Baffle or Plane Baffle, this speaker should be circa 7" diameter to offer the best bandwidth compromise, and the size of the matching baffle would then be very large to avoid acoustic short-circuit that inevitably occurs in the low frequencies, in order to achieve a suitable bass extension - think several Sq.Mtrs. surface...
But it's me, OK ?
T
I'd suggest that if one can hear the box itself then this is simply a bad box, and shouldn't even enter into any sensible comparison. Reflected sound from the rear of the box is perhaps more of a challenge for rectangular commercial examples (that are all many people will have heard), but enlightened members of DIYaudio will know there are designs which control that rather effectively, too.
So assuming a well designed and executed speaker, IMO the main difference is the polar response or directivity. This isn't better or worse, but it will suit different situations and preferences. In the past I had a bigger listening room in which either type would work well, though of course with different results. Now I have a cramped space in which the control offered by a box is much easier to use successfully.
So assuming a well designed and executed speaker, IMO the main difference is the polar response or directivity. This isn't better or worse, but it will suit different situations and preferences. In the past I had a bigger listening room in which either type would work well, though of course with different results. Now I have a cramped space in which the control offered by a box is much easier to use successfully.
I just got 1 CHP-90 set up in its box and it's already distracting me from the gluing the 2nd box. I didn't have any low-value resistors lying around so I had to use an old 12V bulb for the series resistance (approx 3 ohm when cold). That's how impatient I was to start playing some music. Wow! The dinky class-D + bluetooth module doesn't do it justice.
The angular box, where all the usual 90° turns have been replaced with 45° and 60° really seems to help with diffraction. But it really tests my personal limits of what I'm capable of cutting and gluing by hand. A smarter person than I would've long since outsourced it to a flat-pack manufacturer, LOL.
Segue 1...
My understanding of source / amp requirements keeps evolving.
Planned amplifier specs:
-Exicon laterals
+/-15V rails, clipping at approx +/-11V or ~7W (no special rail-to-rail circuitry).
200mA idle with no degen resistors should give square-law class AB with class-A up to about +/-4V. The moderate 6W of idle heat per channel gives some leeway if needed.
Closely related: Segue 2...
I saw some research showing a distorted bell curve for the statistical distribution of signal levels for music, so I'm inspired to write a script that parses WAV files and spits out similar statistics. Based on that, I'll have a better understanding of what to expect when looking at scope levels. Would that leeway be better directed to +/-30V rails and 40W transients? Or bumping up the class-A current to cover say, +/-6V, and soft-clipping the "occasional" peaks (whatever that means, hence the research)?
Peufeu's "distortion free soft clipping" research looks very interesting and I'm leaning towards the low voltage option.
Back to dipoles...
It occurred to me that quite a good speaker could be made, starting with a "bipole", so that the rear wave has clean output unencumbered by pesky magnets. Bass polarity either pressurises the room, or the phase is minimally shifted for cardioid output with slight cancellation if desired. This is achieved with an all-pass crossover that rotates the phase at mid-range and upper frequencies.
None of what you said made sense to me. 180 degrees out of phase is exactly the same as reverse polarity. Maybe show a diagram with two or three sinewaves to illustrate what you mean by the difference between out of phase and reverse polarity being different. I don't see how you're going to do that.
The human ear has been shown to be very insensitive to absolute phase. So all the musing about reflected sound being flipped is only interesting in how that reflected sound is recombine with the direct sound to add to or cancel at different frequencies based on the phase at the listening position. I think the distinguishing feature of the dipole radiation pattern is the total lack of radiation 90 degrees from the panel. That lack of energy up, down and to both sides removes some of the sidewall, ceiling and floor reflections. That along with the cancellation of the low bass and emphasis of upper bass frequencies and woofers flopping in and out at high excursions make me prefer an omni directional speaker.
Out of phase is not necessarily 180 degrees of phase. Out of phase is not "in phase". So 90 degrees of phase rotation is out of phase.
Another note is how many folks equate in/out of phase with constructive/destructive frequency interference. While that is one effect, another is time of arrival.
While many engineers prefer the frequency domain due to the simplification of ODEs to an algebraic framework via Laplace transforms, it causes an oversight in the time domain and non steady-state/impulse behaviour. It all needs to be looked at and somewhere, maybe create a rigourous framework to create repeatable realistic 2 channel playback and avoid all the snake-oilery.
Another note is how many folks equate in/out of phase with constructive/destructive frequency interference. While that is one effect, another is time of arrival.
While many engineers prefer the frequency domain due to the simplification of ODEs to an algebraic framework via Laplace transforms, it causes an oversight in the time domain and non steady-state/impulse behaviour. It all needs to be looked at and somewhere, maybe create a rigourous framework to create repeatable realistic 2 channel playback and avoid all the snake-oilery.
I would like to note that one of the boxiest speakers i ever heard was an OB (with Silver Iris).
dave
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Sounds marketable. You have patents pending, or will the DIY construction article be coming soon?
Standing wave resonances inside the box reradiated out through the cone. Insulation helps to damp/reduce it but not completely eliminate it. Non parallel walls also helps, as do angled internal baffles or reflectors behind the cone. One reason TL often sound less boxy, small bookshelves on stands, too.
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I like an open backed box, with some absorption behind.
https://www.diyaudio.com/community/threads/a-bigun-the-audio-nirvana-super-15.217893/
The idea came from the Hartley “Boffle”.
https://www.diyaudio.com/community/threads/a-bigun-the-audio-nirvana-super-15.217893/
The idea came from the Hartley “Boffle”.
My slot loaded U-frames were (by definition) open back, heavily insulated. There's no other way I could get 4 x 12" woofers in such a 'small' enclosure otherwise. Most incredible subsonic bass I've never heard, only felt. Unfortunately they were a one trick pony that were hard to blend seamlessly with the mids and there aren't that many recordings that could take full advantage of their capabilities. At least I was able to prove that a proper enclosure is not necessary for deep, solid, floor shaking bass.
It comes down to where you want to spend your time. I posted enough details to allow someone to build one in the thread "How to build Spherical Speakers".
If you want the best way to reproduce human voice... there is a very simple formula... simple + simple..
NO BOX, NO CROSSOVER ... AS simple as possible... + Mogami 3013 $4 /FTThere is no need to argue which is better... Please trust your ears.. which one can offer you the most accurate human voice..
This type of option is not for everyone.. It is same as I do not like to drive 4X4 truck.. I want Honda Fit..
If you have bigger budget you can use expensive driver... Low cost driver will give you similar result.....
Expensive Solution: AER Driver + 650 mm Horn
AER + 1280mm horn
In fact you can use any 8 inches full range speaker .
Cost Effective Solution: 2 pieces of pine wood + full range speaker..
Again.. this type of speaker is not for everyone.
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Yes, this type of speaker is not for audiophiles who want good, natural and uncolored sound, with enough bass.
This type of loudspeaker has no bass at all, and it is disgustingly colored.
I have built several different 3-way OB, with crossovers of course, and they sound wonderful. Oh, and they are for everyone!
This type of loudspeaker has no bass at all, and it is disgustingly colored.
I have built several different 3-way OB, with crossovers of course, and they sound wonderful. Oh, and they are for everyone!
If 3-way OB (with passive crossovers) is DSP-ed/linearized down to 30 Hz and filtered below, than it will sound better than any DSP-ed/linearized single-fullrange driver OB, with much more uniform dispersion (which can not be equalized in the case of single-fullrange driver!) and with much more low bass and much more max SPL.
And I highly doubt @vkung will accept DSP in his naive "simply + simply" design of single-fullrange driver OB.
And I highly doubt @vkung will accept DSP in his naive "simply + simply" design of single-fullrange driver OB.
Yes, the more you add the more you will lose ...
Again.. this type of speaker is not for everyone.
I do not care about 30HZ... I care about the fine detail and emotion of the music.. Through the music, I can engage with the singer...
The most accurate to reproduce human voice is matter to me...
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I used to have a Benchmark DAC-3. Soundstage was narrow and forward as compared to the original Topping D90 with AK4499EQ (which also sounded better overall). Gave the DAC-3 to my daughter. Loaned out the Topping to a friend. Have an Andrea Mori DSD prototype dac now. Easily sounds better than either of the two dacs previously mentioned. Just mention that so that you don't think your speakers are the problem if the soundstage isn't good.
To say vkung is naive is a bit unfair because he accepts the limitations of his choices of speaker as a compromise clearly acknowledged.
I understand well vkungs standpoint as it is a part of personal preference and listening experience.
After building many years loudspeakers a quintessence is that a little bit of distortion/colouration can be pleasing to the ear. Some like more, some less.
For the same reason I enjoy certain LPs from the seventies because they make sound.
Example group Jane, German progrock
https://m.youtube.com/playlist?list=PLGzoX18zlfA0OamkOv1S4gVUg1D_06sim
After building many years loudspeakers a quintessence is that a little bit of distortion/colouration can be pleasing to the ear. Some like more, some less.
For the same reason I enjoy certain LPs from the seventies because they make sound.
Example group Jane, German progrock
https://m.youtube.com/playlist?list=PLGzoX18zlfA0OamkOv1S4gVUg1D_06sim
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