[jgazal]

Pardon me if this has already been discussed earlier in the thread but I wonder if anyone has tried or given thought to using the A8/A16 to use an Ambiophonics or Choueri BACCH system to make a PRIR. It should certainly be theoretically possible to do so and I at least would be willing to pay a premium (say, $1000 USD) for someone to allow me to use their rare and expensive BACCH system to make a PRIR. Food for thought as I await my A16 with Canjam 2017 PRIR to show up in the mail in 2-3 months.

Submitted by Hi-Reality on January 20, 2015 - 1:40pm

I thought that once a BACCH-SP system has been properly calibrated for a listener in a particular room, a Smyth Realiser can then be calibrated for him/her, in the same room, by playback of SR's calibration tones via that BACCH-SP system.

In other words, the listener goes through two measurements wearing microphones: first by the BACCH-SP system, then by the Smyth Realiser.

Thus, I thought, the properties of crosstalk cancellation filters of the BACCH-SP would be preserved since the Smyth Realiser creates its 'PRIR' (personalised room impulse response) based on playback via the BACCH-SP filters for the listener.

Have I got it wrong?

(...)

Submitted by Timothy Link on September 6, 2015 - 9:50am

Headphones are by their nature close to perfect crosstalk elimination devices. The Smyth realizer solves the problem of creating an external sound field effect for headphones, but in the process also simulates the crosstalk, which isn't necessary for an external effect (although I know some people add crosstalk to their headphone systems on purpose.)

I emailed Smyth years ago inquiring about the possibility of using their system to simulate a crosstalk eliminated external speaker listening experience. They said there was no reason it wouldn't work, and to my thinking it would work extremely well, better than any in-room cancellation effort.

I suspect it could be done very simply during the calibration phase of for the Smyth system. First set the speakers and listening position in a stereo dipole configuration,with speakers fairly close to each other. When calibrating for the right channel, block any sound from getting to the left ear microphone. When calibrating for the left channel, block any sound from getting to the right ear microphone.

By doing that you will hear through the headphones what seems to be an externalized sound source that sounds like it's coming from a stereo dipole configuration with near perfect crosstalk elimination and no colorations from crosstalk cancellation software.

Ideally you'd take it a step further and compare the coloration of the speaker and room to the source signal and cancel all that out as well, but the Smyth Realizer wasn't made with that in mind. It was made specifically to simulate listening to speakers in a room, with room and speaker effects all simulated.

From personal experience, I have found that a dipole stereo arrangement with a physical barrier can be equalized to counter any coloration induced from the barrier. The result is incredible on some recordings, virtually unnoticeable on others. I never heard it make anything sound worse. It is a pain though to have to straddle the barrier and only enjoy the experience from that one location.

I also tried digital recursive crosstalk elimination but found the sound quality unacceptable no matter how I adjusted it.

I'm sure Bacch is a big improvement with it's customized hrtf and head tracking, and will be reasonably priced soon enough. Combine that with Occulus goggles and you could really feel like you are at the concert hall! Having visual cues that synchronize with the audio cues will make the effect that much better.

http://www.stereophile.com/content/bacch-sp-3d-sound-experience#83rUlIezFALFCkrL.03

dwk123 - 8th February 2012, 02:23 AM

(...)

I've recently become rather intrigued by the Smyth Realiser (www.smyth-research.com).

(...)

My second reaction is that this would seem to be an absolutely ideal way to implement ambiophonics - 'simply' measure a single high-quality mono speaker directly in front, and then separate the channels to eliminate the x-talk component - you get a real measured HRTF response and perfect x-talk cancellation. I'm so intrigued by this idea that I ordered an in-ear binaural mic setup to play with.

http://www.diyaudio.com/forums/multi-way/200040-stereophonic-sound-single-loudspeaker-28.html#post2896681

 

[esimms86]

Thank you!

 

[Erik Garci]

Pardon me if this has already been discussed earlier in the thread but I wonder if anyone has tried or given thought to using the A8/A16 to use an Ambiophonics or Choueri BACCH system to make a PRIR. It should certainly be theoretically possible to do so and I at least would be willing to pay a premium (say, $1000 USD) for someone to allow me to use their rare and expensive BACCH system to make a PRIR. Food for thought as I await my A16 with Canjam 2017 PRIR to show up in the mail in 2-3 months.

It's already possible to make a PRIR without crosstalk. You don't have to use Ambiophonics or BACCH. The quotes below explain how I did it. Since then I have added an A/B switch for the microphones. I also made a PRIR of a Hafler circuit without crosstalk, which seems to improve the sensation of envelopment. I can post details about the A/B switch and the Hafler circuit if anyone is interested.
 
 

  By the way, I recently created a PRIR for stereo sources that simulates perfect crosstalk cancelation. To create it, I measured just the center speaker, and fed both the left and right channel to that speaker, but the left ear only hears the left channel because I muted the mic for the right ear when it played the sweep tones for the left channel, and the right ear only hears the right channel because I muted the mic for the left ear when it played the sweep tones for the right channel. The result is a 180-degree sound field, and sounds in the center come from the simulated center speaker directly in front you, not from a phantom center between two speakers, so they do not have comb-filtering artifacts as they would from a phantom center.
 
Binaural recordings sound amazing with this PRIR and head tracking.

 

  To mute it I unplug the left or right microphone from the Y-junction between sweeps. I set the "post silence" to 8 seconds beforehand to give me enough time. To make it easier I plan to hook up an A/B switch.
 
I actually got the idea from a comment by Timothy Link in this Stereophile article about Dr. Choueiri's BACCH.
http://www.stereophile.com/content/bacch-sp-3d-sound-experience
 
You can also add a rear speaker to the PRIR for the left and right surround channels to achieve a full 360-degree circle like PanAmbiophonics, and additional speakers for hall ambience.

 

[Richter Di]

It's already possible to make a PRIR without crosstalk. You don't have to use Ambiophonics or BACCH. The quotes below explain how I did it. Since then I have added an A/B switch for the microphones. I also made a PRIR of a Hafler circuit without crosstalk, which seems to improve the sensation of envelopment. I can post details about the A/B switch and the Hafler circuit if anyone is interested.

Yes, please.

 

[Erik Garci]

Yes, please.

For the A/B switch, I'm using a Niles PS-1, but any similar switch would work. I'm also using 2 cables, each of which has a 4-pole 3.5mm male plug on one end (1/8" tip/ring/ring/sleeve), and 3 RCA male plugs on the other end.
 
The pinout of each cable is as follows:
Tip to RCA0 pin
Ring1 to RCA1 pin
Ring2 to RCA2 pin
Sleeve to Shield of all RCA
 
Warning: Some cables don't conform to this pinout and should not be used.
 
Connect Cable1's 3.5mm plug to the MIC jack on the Realiser A8's front panel.
Connect Cable2's 3.5mm plug to the bottom jack on the Y-junction.
Join Cable1's RCA0 plug and Cable2's RCA0 plug with an RCA female coupler.
Connect Cable1's RCA1 plug to the switch's "Common Left" RCA jack.
Connect Cable1's RCA2 plug to the switch's "Common Right"  RCA jack.
Connect Cable2's RCA1 plug to the switch's "A Left" RCA jack.
Connect Cable2's RCA2 plug to the switch's "B Right" RCA jack.
 
Select "A" on the switch to use the left microphone and mute the right microphone.
Select "B" on the switch to use the right microphone and mute the left microphone.
 
Later I will explain the Hafler circuit.
 

 

[GU1DO]

Hi All ..
 
Guys i am very interested in the Realiser A16 but i have one concern which is regarding the PRIR calibration
can i do it with my 5.1 home theater ?  is it enough ? i dont have super setup , it is a reguler home theater
 
Also regarding the rack edition, is it available now with the special pre order price ?
i dont like the headphone stand edition
 
One more thing ,, can anybody provide a large (high quality) picture for the back of the Realiser A16
to see the connections .. if there is a beta manual is better ( just to know how it would be connected )
 
Thanks in advance ..

 

[esimms86]

Erik, thank you for the excellent and helpful posts. I also have a number of binaural files that I have high expectations for re: PRIR listening experiences.

Esau

 

[Sanctuary]

One thing I had not thought of until recently for some reason is: all of the videos for the complete PRIR process show it being done with and without the headphones on.  Does this mean that for each different pair of headphones you have to record a new PRIR? 
 

  Hi All ..
 
Guys i am very interested in the Realiser A16 but i have one concern which is regarding the PRIR calibration
can i do it with my 5.1 home theater ?  is it enough ? i dont have super setup , it is a reguler home theater
 
Also regarding the rack edition, is it available now with the special pre order price ?
i dont like the headphone stand edition
 
One more thing ,, can anybody provide a large (high quality) picture for the back of the Realiser A16
to see the connections .. if there is a beta manual is better ( just to know how it would be connected )
 
Thanks in advance ..

 
You can do it for an entire 16 speaker setup with a single speaker (it would be a lot more time consuming that way however), so you'll be fine.

 

[Sordel]

  One thing I had not thought of until recently for some reason is: all of the videos for the complete PRIR process show it being done with and without the headphones on.  Does this mean that for each different pair of headphones you have to record a new PRIR? 

 
I'm not sure of the nomenclature, but I believe that the PRIR process is one thing, done without headphones and then you register the headphones to the system by doing a different process involving putting in the in-ear microphones and testing the output of the headphones. Once you have the PRIR you never need to go back and take measurements of the same room because the system applies processing for the headphones after the processing that simulates the inclination of your head to the virtual speakers.

 

[Sanctuary]

   
I'm not sure of the nomenclature, but I believe that the PRIR process is one thing, done without headphones and then you register the headphones to the system by doing a different process involving putting in the in-ear microphones and testing the output of the headphones. Once you have the PRIR you never need to go back and take measurements of the same room because the system applies processing for the headphones after the processing that simulates the inclination of your head to the virtual speakers.

This is actually what I was hoping was the case.  Otherwise, I don't know how the room exchanges could really even be functional.  Or at least accurate for different people.

 

[jazzfan]

 

  One thing I had not thought of until recently for some reason is: all of the videos for the complete PRIR process show it being done with and without the headphones on.  Does this mean that for each different pair of headphones you have to record a new PRIR? 

 
I'm not sure of the nomenclature, but I believe that the PRIR process is one thing, done without headphones and then you register the headphones to the system by doing a different process involving putting in the in-ear microphones and testing the output of the headphones. Once you have the PRIR you never need to go back and take measurements of the same room because the system applies processing for the headphones after the processing that simulates the inclination of your head to the virtual speakers.

 
Sordel, you're correct. To elaborate, the Realiser measurement capture process requires two separate measurements - a Personalized Room Impulse Response (PRIR) and a Headphone Equalization (HPEQ) measurement. Both require the use of supplied in-ear microphones. The first measurement, a PRIR, does not require the use of headphones, and must be taken in the room with the speakers to be measured. The second measurement, an HPEQ, is taken with headphones placed on the listener. The HPEQ can be taken at a later time and in a different location, but generally, is taken immediately following the PRIR measurements so the two measurements can be combined and immediately tested.
 
If you have multiple headphones, you can maintain separate HPEQs for each. A PRIR and HPEQ pair can be loaded into a preset and you can switch between presets so you can compare the sound of various headphones. Theoretically, they should all sound the same, and all of my top headphones produce a convincing virtual experience with the Realiser. However, in practice, I found the quickness and transparency of my SR-009 best suited for the Realiser.

 

[phoenixdogfan]

Alternatively, you could skip the HPEQ process  entirely if you have something like a Sonarworks custom headphone equalization curve and your  source was your PC running JRiver or Foobar with the SW plugin feeding ther SVS Realizer.

 

[castleofargh]

  Alternatively, you could skip the HPEQ process  entirely if you have something like a Sonarworks custom headphone equalization curve and your  source was your PC running JRiver or Foobar with the SW plugin feeding ther SVS Realizer.

not really IMO. sonarwork customizes for the headphone and some average human target response, not for a specific guy under the headphone. no doubt it's better than using most headphones without any compensation at all, but it's lacking a significant part of the customization.

 

[phoenixdogfan]

So does Sonarworks.  It's target curve is close if not identical to the Harman Target curve.

 

[castleofargh]

you're missing my point. the target for them is to get a particular signature on their dummy head, not on your head with your ears. having couplers in my very own ears, will give me the response for the headphone (or the room) to my ears, minus the ear canal for practical reasons. one is an average target, the other is a custom target.