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EarSpace!!!!

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41 minutes ago, STC said:

Could you please ease list down all the software and impulse response you use to “to reproduce the effects of the room and the characteristic sound of the playback system, including the speakers for another listener, with a different system at a different location.”  

 

That at will be helpful for me to understand how you are dealing with the convolution because I am doing it very different understanding. At times, you are on same page but at times you are saying something else what IRs not supposed to do. That’s where the confusion is. 

 

IR is a measurement of a system response to an infinitely short pulse.  Convolution is a mathematical operation, applying a function to a function. Convolving a waveform with an impulse response results in applying the same system response that was measured to the new waveform. In effect, it applies the same distortions, reflections and other system characteristics of the originally measured system.

 

I use REW to compute impulse response from a sine sweep. The sine sweep measurements are done from my listening position using a measurement microphone and my speaker system.

 

I use HQPlayer to apply this generated impulse response to my playback system.

 

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11 minutes ago, pkane2001 said:

 

IR is a measurement of a system response to an infinitely short pulse.  Convolution is a mathematical operation, applying a function to a function. Convolving a waveform with an impulse response results in applying the same system response that was measured to the new waveform. In effect, it applies the same distortions, reflections and other system characteristics of the originally measured system.

 

I use REW to compute impulse response from a sine sweep. The sine sweep measurements are done from my listening position using a measurement microphone and my speaker system.

 

I use HQPlayer to apply this generated impulse response to my playback system.

 

 So this impulse response is without correction?  

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1 minute ago, STC said:

 So this impulse response is without correction?  

 

Impulse response is a measurement of the overall system, all warts, reflections, and corrections included.

 

No correction is implied by IR. But, if your system has correction activated during measurement, it will also be part of the captured IR. 

 

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7 minutes ago, pkane2001 said:

 

Impulse response is a measurement of the overall system, all warts, reflections, and corrections included.

 

No correction is implied by IR. But, if your system has correction activated during measurement, it will also be part of the captured IR. 

 

 

Ok. That cleared the big confusion I was having. I use the IR to correct the room defect. That was long time ago. So you are just using it to feed your headphones listening to sound like listening to your speakers in the room. Am I correct?

But that will not correct the inside your head perspective with headphones. Maybe the tonal balance will be similar. 

 

Edit: I think I got this mixed up with the other thread using IR with sloping treble. My apologies. 

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1 minute ago, STC said:

 

Ok. That cleared the big confusion I was having. I use the IR to correct the room defect. That was long time ago. So you are just using it to feed your headphones listening to sound like listening to your speakers in the room. Am I correct?

But that will not correct the inside your head perspective with headphones. Maybe the tonal balance will be similar. 

 

It's much more than changing tonal balance, since reflections/reverb are part of the captured IR. It makes headphones sound more like the sound is playing in a room, through a speaker system.  Convolution with IR can be used to do crossfeed and other types of processing, but in this case, I'm suggesting a very different experiment - simply reproducing the sound quality of someone else's speaker/room system in my own headphone listening. If I upload my IR file, you can use it to listen to my speaker/room combination through your own system and headphones.

 

Take a look at OOYH product that does something similar. Came across this yesterday, but as I said, it's not working well for me. Others claim success with it, so it may just be me:

https://fongaudio.com/out-of-your-head-software/

 

I'll start a separate thread on the topic of exchanging IR files where everyone can share the sound of their system with everyone else. Hopefully someone will be willing to try :)

 

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8 minutes ago, pkane2001 said:

If I upload my IR file, you can use it to listen to my speaker/room combination through your own system and headphones.

 

I am confident enough to say  that under blind test, your IR will not sound like your room in my system. 

 

There was another thread by a manufacturer who uses true stereo IR and XTC. There they provided some good explanation about the IRs.

 

firstly, when I convolute your IR with the original recordings, I am adding additional reverbs and errors to the frequency response of the recordings. This reverbs maybe true acoustics signature of your room but the original IR was recorded of room acoustics of 360 degrees directions. Unless your microphone is pointed to one direction, the recorded IR will have omnidirectional IR. This can give a likeable sound but never the accurate sound. Venue’s acoustics signature must be captured at each reflecting angles and reproduced the same. Only then, it will sound close enough like the orginal event. 

 

This is doesn’t mean the sound you perceive is different. You will hear your room sound because the acoustics signature is stored in your memory and when you pick the slightest hint of the acoustics signature, your brain equates the sound to your room.  This is the same as the claims made that they can hear full orchestra sound like in a concert hall with stereo setup. It is there because your brain associates the reverbs to the audio memory and creates the imaginary soundfield. It is perfectly valid until you hear a better system that creates the event. 

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1 minute ago, STC said:

There was another thread by a manufacturer who uses true stereo IR and XTC. There they provided some good explanation about the IRs.

 

firstly, when I convolute your IR with the original recordings, I am adding additional reverbs and errors to the frequency response of the recordings. This reverbs maybe true acoustics signature of your room but the original IR was recorded of room acoustics of 360 degrees directions. Unless your microphone is pointed to one direction, the recorded IR will have omnidirectional IR.

 

Our ears are not omnidirectional, and neither is a microphone. Neither one will capture 360 degrees to reproduce system/room response. Could the captured IR be different when pointing the mic in different directions? Probably. How different? And what if I point the microphone in the same direction as my ear at the listening position? Will this capture something closer to my listening IR? 

 

If you can point me to the thread where this was discussed, I'd love to try to understand what that manufacturer was saying about IR.

 

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18 minutes ago, pkane2001 said:

 

Our ears are not omnidirectional, and neither is a microphone. Neither one will capture 360 degrees to reproduce system/room response. Could the captured IR be different when pointing the mic in different directions? Probably. How different? And what if I point the microphone in the same direction as my ear at the listening position? Will this capture something closer to my listening IR? 

 

If you can point me to the thread where this was discussed, I'd love to try to understand what that manufacturer was saying about IR.

 

 

If hearing is not omnidirectional than you won’t be hearing people who talk to you from behind you. 

 

If hearing is not Omnidirectional anechoic chamber should not make a difference to you. 

 

If hearing is not omnidirectional, side wall and rear wall treatment will not make a difference to you. 

 

There are omnidirectional microphone . Your multi channel SACDs rear channels are usually recorded with those. 

 

https://www.dpamicrophones.com/mic-university/directional-vs-omnidirectional-microphones

 

I can give you my IRs but they are true stereo, i.e you need to convolute them with 4 channels convolution engine such as SIR2 or WaveIR. HQplayers convolution engine is most likely only stereo. If you are keen I will modify them for you. 

 

 

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23 minutes ago, STC said:

If hearing is not omnidirectional than you won’t be hearing people who talk to you from behind you.

If hearing was omnidirectional you wouldn't be able to tell that someone is behind you and not in front. Our ears have some response in all directions, but it varies.

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4 minutes ago, mansr said:

If hearing was omnidirectional you wouldn't be able to tell that someone is behind you and not in front. Our ears have some response in all directions, but it varies.

 

Onmidirectional hearing doesn’t mean they are linear at all direction. That’s where HRTF comes in. 

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1 minute ago, STC said:

 

Onmidirectional hearing doesn’t mean they are linear at all direction. That’s where HRTF comes in. 

 

I guess I'm missing your point. You first said that IR cannot be accurate because hearing is omnidirectional, and then you point to omnidirectional microphones that can capture IR. So where's the problem?

 

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44 minutes ago, STC said:

I can give you my IRs but they are true stereo, i.e you need to convolute them with 4 channels convolution engine such as SIR2 or WaveIR. HQplayers convolution engine is most likely only stereo. If you are keen I will modify them for you. 

 

 

HQPlayer can apply separate convolution to 4 left and 4 right channels. 

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1 minute ago, pkane2001 said:

 

I guess I'm missing your point. You first said that IR cannot be accurate because hearing is omnidirectional, and then you point to omnidirectional microphones that can capture IR. So where's the problem?

 

 

The problem is direction of the room acoustics reaching your ears. They reach from various angles at your ears/microphones. They have direction and different frequency response. To reproduce them you must also have the speakers at the same angle those sound arrive at your ears. This is the reason why recording engineers will always place the microphone within the critical distance from the direct sound. This is to avoid capturing the true room acoustics which will make the direct sound muddy because “surround” ambience sound is now confined to the two spots of the front speakers. 

 

Here is a a crude analogy, when you record a performance on stage, you are expected to put the speakers where the performers were. Now, if you decide to put your speakers behind you then you are producing the frontal soundstage from the rear. It will sound wrong. But if you were to reverse the microphone towards the audience and record them during the applause, the sound will sound correct if the speakers placed at the back. 

 

This is is one reason why during a performance the applause is always do not sound correct because it will come from the front stage. 

 

In in case of IR, it comes from everywhere and therefore it should be confined to one spot and expect it to recreate the venue acoustics signature. 

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4 minutes ago, pkane2001 said:

 

HQPlayer can apply separate convolution to 4 left and 4 right channels. 

 

True comvolution deals with left and right channel for each channel. Anything less than that is a compromise.  

 

The short explanation is, a sound originates from the left side of the stage will be reflected from the left  and right wall too. So the left channel must be convinced to both channels. 

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22 minutes ago, STC said:

Onmidirectional hearing doesn’t mean they are linear at all direction. That’s where HRTF comes in. 

That's exactly what omnidirectional means. Otherwise the word would be pointless.

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Just now, STC said:

 

True comvolution deals with left and right for each channel. Anything leads than that is a compromise.  

 

The short explanation is, a sound originates from the left side of the stage will be reflected from the left  and right wall too. So the left channel must be convinced to both channels. 

 

Again, I'm afraid I'm missing your point. HQP can apply the same or different IR files to each of the 8 channels. Depends on your needs. This was in answer to your statement:

 

54 minutes ago, STC said:

HQplayers convolution engine is most likely only stereo.

 

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9 minutes ago, pkane2001 said:

Again, I'm afraid I'm missing your point. HQP can apply the same or different IR files to each of the 8 channels. Depends on your needs.

That's not enough. In the stereo case, you need a cross-wise component in addition to the direct one. The impulse response has four parts: left-to-left, left-to-right, right-to-right, and right-to-left. The left output consists of the left input convolved with the left-to-left IR plus the right input convolved with the right-to-left IR, and so on. I have no idea if HQP can do this.

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6 minutes ago, mansr said:

That's not enough. In the stereo case, you need a cross-wise component in addition to the direct one. The impulse response has four parts: left-to-left, left-to-right, right-to-right, and right-to-left. The left output consists of the left input convolved with the left-to-left IR plus the right input convolved with the right-to-left IR, and so on. I have no idea if HQP can do this.

 

Yes, absolutely. This is how I apply crossfeed in HQP:

image.thumb.png.63ea978b84b4f858cfb5c90a119d5e74.png

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6 hours ago, pkane2001 said:

Again, I'm afraid I'm missing your point. HQP can apply the same or different IR files to each of the 8 channels. Depends on your needs. This was in answer to your statement:

 

From the manual of HQplayer. It is not even stereo. But you are also using matrix to mix. How did you capture the different  IR? 

 

Convolution engine requires impulse responses to be mono RIFF (WAV) format files. If some of the channels don't need processing, or are not used, clearing the filename will disable convolution engine for those channels

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Note how incredibly messy this all becomes when one tries to mechanically compensate - one is swamped by contradictory requirements - best solution: let that marvellous DSP inside one's skull do it all - it's had a lifetime of practice getting it right ... ^_^.


Frank

 

http://artofaudioconjuring.blogspot.com/

 

 

Ahhh, Mankind ... Porsche intellect, Trabant emotions ...

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2 minutes ago, fas42 said:

Note how incredibly messy this all becomes when one tries to mechanically compensate - one is swamped by contradictory requirements - best solution: let that marvellous DSP inside one's skull do it all - it's had a lifetime of practice getting it right ... ^_^.

 

Nonsense. Why bother with electronic reproduction at all, Frank? That's incredibly complicated. Best solution is to just stand down-wind from an acoustic performance and let your ears get it right.

 

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