That rear fired information part of the recording (picked up by the mics in the room it was made in) is conveyed by the speakers facing your ears. The garbage re-created by the tweeters firing it back into YOUR room (a second time) is an added artifical acoustic event not originally in the recording itself.
Sorry, you dont understand the point I made before.
Sorry, you dont understand the point I made before.
Then it is clear that '...YOUR room...' is a significant factor in sound reproduction, by changing the acoustic signature of the loudspeakers. How does this negate the addition of extra drivers in to improve the listening experience? Are you suggesting that any configuration other than a pair of boxes housing two or three drivers in each and pointing almost directly at the listener will have a negative effect on the listening experience in every environment for every listener?
Everything is a compromise. Rooms have a gigantic range of acoustics. Image/Soundstage is not as important to some who value other assets. The (artificailly wide & vague) soundstage of an omni like the DDD would be a valued asset to someone moving around the listening room (workroom?).
dave
dave
A rear firing HF driver will only be heard as a delayed reflection from rear and partially side boundaries. That smears the forward radiating audio from the speaker and causes destructive interference, unless you delay the forward radiating audio so that its in time alignment with the rear reflected audio. That delay will depend on how far the speaker is from other side and rear boundaries. Most speakers that have rear facing drivers radiate audio from all HF drivers in sync (discounting minute phase delays from the crossover network).
If that type of extra fluff is what you like as an added effect to your sound, its up to you, but it's not conducive to accurate stereo imaging and faithful reproduction of the recording as the engineer intended it to be. Its physically impossible to state that a delayed reflection of any portion of audio is going to help faithfully and accurately recreate a recorded performance in a believable three dimensional way in any listening space regardless of how reflective or inert it may be.
If that type of extra fluff is what you like as an added effect to your sound, its up to you, but it's not conducive to accurate stereo imaging and faithful reproduction of the recording as the engineer intended it to be. Its physically impossible to state that a delayed reflection of any portion of audio is going to help faithfully and accurately recreate a recorded performance in a believable three dimensional way in any listening space regardless of how reflective or inert it may be.
I agree with you. Thats sort of the main reason companies like Bose do what they do, making the listening experience more casual and second priority to another activity as opposed to someone who listens sitting in the sweet spot and solely concentrates on the listening experience as the primary source of entertainment.
In complete dipoles, like electrostats, or open back planars, no delay is implemented or required. Period.
It really depend on recording. In a studio recording, the microphone is only quite often a feet or so, or even less. Therefore the main sound overwhelms any reflections. More so when the studio is normally fully absorbent in sound. This is opposed to be if you were listening to the same instrument or person in a normal room where the sound eminating is semi omnidirectional rather than just forward. Your brain is looking for the echoes as a cue to the size of your room.
It is different from a recording of an orchestra where it is done in a live room and the microphone is many meters away.
This us the reason, why if you called someone on the mobile, you could tell they are in the toilet. Our ears/brain is very sensitive to this cue. That is why people like the sound of open baffle.
It is not a case of adding extra sauce, more of a case adding in the echoes that was not recorded during a studio recording.
Oon
It is different from a recording of an orchestra where it is done in a live room and the microphone is many meters away.
This us the reason, why if you called someone on the mobile, you could tell they are in the toilet. Our ears/brain is very sensitive to this cue. That is why people like the sound of open baffle.
It is not a case of adding extra sauce, more of a case adding in the echoes that was not recorded during a studio recording.
Oon
Time smear. It can also be a problem inside a loudspeaker. It is more or less inherent in dipoles/OBs.
Unless the rear bounce is time delayed so that it is perceived as a different sound (not possible in normal size rooms) one will get an artificially enhanced soundstage. Imaging likely goes out the window.
dave
In a dipole, in a normal size room, direct front signal arrives tens of milliseconds earlier than back propagating sound, projected towards back wall or under the angle to the ceiling, will be clearly heard as two different sounds. First arriving front as main sound, and room reflection as spacial information.
No processing or delay required. Assuming dipole far enough from the wall.
No processing or delay required. Assuming dipole far enough from the wall.
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Hi,
You just need to add to it through the main speaker line. As if it was another parallel tweeter. Simple 1 or 2 uF cap will do to test the effect. It doesn't have to be expensive tweeter. Our brain actually doesn't care, it recognises that this is a reflection and therefore it will be distorted. As long as it is delayed by 10ms or so.
At 1uF to 2uF you are adding only energy to the 10kHz and above. So it really doesn't add much to the music. Crossing over low may add more to energy of the music and may impact the tonal balance too much. Most speakers are defficient above 10kHz anyway.
Choose a tweeter with a good 10 to 20kHz response. Preferably 8 ohm so you don't overload the system. I have used visaton SC5, miniature 1/2" tangband tweeter etc. For first cut, you can just try with tweeter you have lying around.
The thread mentioned Wesayso gives more complicated but better control and better effect. If you want introduce in DSP for delay etc.
Moving on you could do second order crossover, add resistor to attenuate etc.
Oon
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I find if you confine to frequencies above 10kHz, integration is much easier. The wavelength is now so short you don't have to worry about interference effects.
Dispersion for most speakers below 10kHz is generally reasonably high that it already generates quite a bit of reflections so not really necessary to add more....
Oon
So dipoles and OBs have just been an artificial trick all this time, on the same level of trickery as, say, a polk SDA? They sure sell!
I've been thinking for a while now my OBs have a pretty nice soundstage... Must be because the highs arent projected out of phase and toward the back wall, just forward.
Lost as usual!
I've been thinking for a while now my OBs have a pretty nice soundstage... Must be because the highs arent projected out of phase and toward the back wall, just forward.
Lost as usual!
