Smyth SVS Realiser - PRIR Exchange Thread
Aug 12, 2012 at 12:35 PM Post #136 of 404
Hi Darin
 
Thank you very much for your excellent PRIRs and documentations, I think you are an experienced "PRIR hunter"!!!!
 
I've placed some of your PRIRs as impulse responses into SVS Demo folder (foobar instructions in process), they works good for me in mainstream and classic music, too.
 
!!! I've quickly checked out your last posted PRIRs from Ivan's House, they have a big correlation problem: center and sub are good (coefficient 0,5 -0,9) , the other speakers are out of phase / opposite in phase.
 
A comparison with all other aligned dropbox PRIRs in my daw shows correlation coefficients in the range of 0,5 - 0,9, which is normal with room reflections.
 
Please try this with Ivan's House / and other PRIRs:
 
a) With pink noise and all channels on the center position must ever located in front - use MODE (2x). Works with nearly all PRIRs, especially  ITU sets like MSM.
 
b) MODE: L and R on (virtual center) center position between L/R must be stable in the middle and than add C, the front localisation should be improved.
 
In a) and b) center position in Ivan's House is out of phase ... no front localisation is possible.
 
Please give me the distance between head and speakers at PRIR mesurement and the room dimensions of Ivan's House. The correlation problem could be a standing wave situation. I try to figure out this in my daw changing phase alignment of surround speakers. Nevertheless the Triad speakers sounds very good ...
 
Bye for now!
 
Aug 12, 2012 at 1:28 PM Post #137 of 404
Quote:
Hi Darin
 
Thank you very much for your excellent PRIRs and documentations, I think you are an experienced "PRIR hunter"!!!!
 
I've placed some of your PRIRs as impulse responses into SVS Demo folder (foobar instructions in process), they works good for me in mainstream and classic music, too.
 
!!! I've quickly checked out your last posted PRIRs from Ivan's House, they have a big correlation problem: center and sub are good (coefficient 0,5 -0,9) , the other speakers are out of phase / opposite in phase.
 
A comparison with all other aligned dropbox PRIRs in my daw shows correlation coefficients in the range of 0,5 - 0,9, which is normal with room reflections.
 
Please try this with Ivan's House / and other PRIRs:
 
a) With pink noise and all channels on the center position must ever located in front - use MODE (2x). Works with nearly all PRIRs, especially  ITU sets like MSM.
 
b) MODE: L and R on (virtual center) center position between L/R must be stable in the middle and than add C, the front localisation should be improved.
 
In a) and b) center position in Ivan's House is out of phase ... no front localisation is possible.
 
Please give me the distance between head and speakers at PRIR mesurement and the room dimensions of Ivan's House. The correlation problem could be a standing wave situation. I try to figure out this in my daw changing phase alignment of surround speakers. Nevertheless the Triad speakers sounds very good ...
 
Bye for now!


Hi jlejle,
 
So you are able to read/decode the PRIR files and then somehow use that info in Foobar to simulate the Realiser processor? I am surprised that would work at all...Assuming it works, that means someone can use these PRIR's and listen to music with the PRIR's in Foobar without having to use a Realiser?
 
What are the impulse responses? I've looked at the stuff you uploaded to the Dropbox folder, but I can't figure out what all the files are for. I take it the files are for Foobar?
 
Anyway, you definitely know what you are talking about because I can see exactly what you are saying about Ivan's room PRIR and the L and R being out of phase. This room was the first time I have actually measured a 7.1 system. All the other PRIR's are from 2 channel systems. With 2 channels, the center is virtually created, of course. With Ivan's system, you're right. The sound is definitely weird when I have just the L and R channels. I should get a stable center image since the L and R signals are the same. However, I get no center image. If I just listen to the center channel, then that localization is fine.
 
Unfortunately I did not take any measurements of the dimensions of the room. All we measured were speaker azimuth angles. I could make a rough guess, but I don't think that would be nearly as accurate as you need. Maybe I can ask Ivan for the dimensions and distances in his room.
 
Interesting...
 
-Darin
 
Aug 12, 2012 at 1:49 PM Post #139 of 404
Quote:
"you should adjust the channel levels using the pink noise generator one channel at a time until they all sound equal in terms of volum" How is this done ?

 
Press "Menu" and then the channel you want to adjust. (not the number buttons, but the L,C,R, LS, etc. buttons on the top half of the remote).
 
For example, here's the steps to adjust the level of the Ls channel:
 
Press Menu
Press LS
Press down twice to get to LS vSPKR SETUP2
Press OK
Press Down once
Press left and right arrows to adjust the REL VOL level for that channel.
Press OK when done
Press Exit
 
Do this for each channel.
 
Actually before you do the adjustments, put the Realiser into Pink Noise mode or the Music Loop mode and solo the channel you are adjusting.
 
Then once you have all the channels adjusted, press Menu, and then the preset number you are using and save the preset. Otherwise, you will lose those settings if you power off the Realiser. Once you get it right, I would also recommend saving that preset to SD card just so you don't lose those settings when you need to change the preset.
 
-Darin
 
Aug 12, 2012 at 1:52 PM Post #140 of 404
Quote:
 
Press "Menu" and then the channel you want to adjust. (not the number buttons, but the L,C,R, LS, etc. buttons on the top half of the remote).
 
For example, here's the steps to adjust the level of the Ls channel:
 
Press Menu
Press LS
Press down twice to get to LS vSPKR SETUP2
Press OK
Press Down once
Press left and right arrows to adjust the REL VOL level for that channel.
Press OK when done
Press Exit
 
Do this for each channel.
 
Actually before you do the adjustments, put the Realiser into Pink Noise mode or the Music Loop mode and solo the channel you are adjusting.
 
Then once you have all the channels adjusted, press Menu, and then the preset number you are using and save the preset. Otherwise, you will lose those settings if you power off the Realiser. Once you get it right, I would also recommend saving that preset to SD card just so you don't lose those settings when you need to change the preset.
 
-Darin


There's no way to get the levels matched accurately. You just have to guess. It's not easy. We need a virtual SPL meter. Seems like the Realiser has enough information to actually do a virtual SPL measurement at the listeners ears.
 
Aug 12, 2012 at 6:01 PM Post #142 of 404
Quote:
 
 
Please try this with Ivan's House / and other PRIRs:
 
a) With pink noise and all channels on the center position must ever located in front - use MODE (2x). Works with nearly all PRIRs, especially  ITU sets like MSM.
 
b) MODE: L and R on (virtual center) center position between L/R must be stable in the middle and than add C, the front localisation should be improved.
 
In a) and b) center position in Ivan's House is out of phase ... no front localisation is possible.
 
Please give me the distance between head and speakers at PRIR mesurement and the room dimensions of Ivan's House. The correlation problem could be a standing wave situation. I try to figure out this in my daw changing phase alignment of surround speakers. Nevertheless the Triad speakers sounds very good ...
 
Bye for now!

I'm having trouble understanding these instructions.  What does "must ever located in front" mean?
 
Aug 13, 2012 at 2:07 AM Post #143 of 404
Quote:
I'm having trouble understanding these instructions.  What does "must ever located in front" mean?


I think what he means is that with any PRIR and the L and R channels outputting the same signal, there should always be a solid center image in front, between the L and R speakers, as it would in real life.
 
Aug 13, 2012 at 2:17 AM Post #144 of 404
Quote:
Hi Darin
 
Thank you very much for your excellent PRIRs and documentations, I think you are an experienced "PRIR hunter"!!!!
 
I've placed some of your PRIRs as impulse responses into SVS Demo folder (foobar instructions in process), they works good for me in mainstream and classic music, too.
 
!!! I've quickly checked out your last posted PRIRs from Ivan's House, they have a big correlation problem: center and sub are good (coefficient 0,5 -0,9) , the other speakers are out of phase / opposite in phase.
 
A comparison with all other aligned dropbox PRIRs in my daw shows correlation coefficients in the range of 0,5 - 0,9, which is normal with room reflections.
 
Please try this with Ivan's House / and other PRIRs:
 
a) With pink noise and all channels on the center position must ever located in front - use MODE (2x). Works with nearly all PRIRs, especially  ITU sets like MSM.
 
b) MODE: L and R on (virtual center) center position between L/R must be stable in the middle and than add C, the front localisation should be improved.
 
In a) and b) center position in Ivan's House is out of phase ... no front localisation is possible.
 
Please give me the distance between head and speakers at PRIR mesurement and the room dimensions of Ivan's House. The correlation problem could be a standing wave situation. I try to figure out this in my daw changing phase alignment of surround speakers. Nevertheless the Triad speakers sounds very good ...
 
Bye for now!


Wow jlejle,
 
I am not sure how you know all this stuff or how you are measuring the impulse responses of the PRIR files, but you are very smart!
 
So, after doing the L+R test and seeing that the L and R channels were out of phase, I e-mailed Ivan and asked him about it.
 
He just called me and said that he had noticed that something wasn't right, but could not figure out what it was. Because he mostly watches 5.1 or 7.1 content, the center speaker outputs the center image. He was not able to pinpoint the reason why it still didn't sound right.
 
I asked him to check the phase of the L and R speakers and sure enough, the Right speaker was connected out of phase! A few days prior to the PRIR measurement, he and a friend were doing some installing/testing and they disconnected the front speakers. It ends up his friend accidentally hooked up the right speaker out of phase!
 
He was really amazed that the Realiser duplicated his system exactly including the out of phase speaker and that someone who has never been in his theater was able to hear and diagnose the problem. Pretty cool.
 
Of course it's a bummer for me since my PRIR now has the right channel out of phase. Does anyone know if there's a way to change the phase of a channel in the Realiser? I doubt it...
 
-Darin
 
Aug 13, 2012 at 12:52 PM Post #145 of 404
Hi Darin,

I'm not able to read/decode the PRIRs, I take a spike impulse snapshot of each PRIR channel in TD mode (0°) and cut it with exact sample position to generate an impulse response file (IR), like the realiser itself.

The snapshot, the "IR" file, contains all artefacts in signal chain from the input to the output of the realiser.

This procedure is used in many applications to preserve the sound of special settings from some unpayable/valuable devices, like reverbs or musical instruments. In real rooms you can use a gun (!!!) or a sweep signal, like the realiser.

Yes, the files can be used in foobar, but you need a embedded host that can play simultaneously up to eight stereo IR players, like console, bidule, mulch, see pictures in demo folder.

You can use the IRs in all stereo impulse response players you like. Your signals/music gets through this IR players and shapes the signals like played through the realiser. It's genuine and very fast, look into the instruction.pdf file how it works (read first instructions.txt).

A word to use the PRIRs in PC/DAW:

I ask Mike Smyth last year about the possibility to create a dongled standalone/VST-plugin to play PRIRs in PC and to build a user interface to control realiser settings with PC (especially if more realisers are synchronized togehter).
 
It can help hearing sources without realiser-latency of 15 ms, make it possible to play music in sync in any room you've recorded with the realiser (it works in simulation!!!) and code SVS-music faster than through the realiser. Hear the demos made with your own PRIRs!

Until today there were no answer about that. Ok, I've contacted my dealer (he's watching this forum too, I think :wink:) to "translate" this idea by another way. We have to wait ...

Out of phase problem

I know, the realiser is a very good room diagnostic tool. I'm glad to hear that Ivan's House sounds "normal" again!

In the past, working sometimes on stage, this problem occurs by doing some "tests" quicky before soundchecks ... oh, oh, it rings a bell ...

By working with daw applications and multichannel stuff it is a major purpose and not a secret to control correlation coefficient, therefore I use such plugins in input and output channels all the time.

In fact it may possible, to invert the phase of the recorded PRIR. But it's no good idea, because it's not the real room anwser - there maybe essential differences in reflections driving loudspeaker membrane forward or backward first time in low frequency < 500 Hz. But I try it out later with IR files ... and with two "real" recordings - one with a screwly speaker - than looking on spectrum analyser and see.
 
Hope it's not too much terrible technical stuff ...

Jürgen
 
 
Aug 13, 2012 at 3:02 PM Post #146 of 404
Quote:
 
Of course it's a bummer for me since my PRIR now has the right channel out of phase. Does anyone know if there's a way to change the phase of a channel in the Realiser? I doubt it...
 
-Darin

It's really too bad because otherwise the system sounds quite good to my ears (via several of the users you measured).  If you ever get a chance to redo this, it would be nice!
 
Reading Jurgen's posts makes me wish I were an audio engineer and not just a music listener.  
 
Aug 13, 2012 at 3:05 PM Post #147 of 404
Quote:
Hi Darin,

I'm not able to read/decode the PRIRs, I take a spike impulse snapshot of each PRIR channel in TD mode (0°) and cut it with exact sample position to generate an impulse response file (IR), like the realiser itself.

The snapshot, the "IR" file, contains all artefacts in signal chain from the input to the output of the realiser.

This procedure is used in many applications to preserve the sound of special settings from some unpayable/valuable devices, like reverbs or musical instruments. In real rooms you can use a gun (!!!) or a sweep signal, like the realiser.

Yes, the files can be used in foobar, but you need a embedded host that can play simultaneously up to eight stereo IR players, like console, bidule, mulch, see pictures in demo folder.

You can use the IRs in all stereo impulse response players you like. Your signals/music gets through this IR players and shapes the signals like played through the realiser. It's genuine and very fast, look into the instruction.pdf file how it works (read first instructions.txt).

A word to use the PRIRs in PC/DAW:

I ask Mike Smyth last year about the possibility to create a dongled standalone/VST-plugin to play PRIRs in PC and to build a user interface to control realiser settings with PC (especially if more realisers are synchronized togehter).
 
It can help hearing sources without realiser-latency of 15 ms, make it possible to play music in sync in any room you've recorded with the realiser (it works in simulation!!!) and code SVS-music faster than through the realiser. Hear the demos made with your own PRIRs!

Until today there were no answer about that. Ok, I've contacted my dealer (he's watching this forum too, I think :wink:) to "translate" this idea by another way. We have to wait ...

Hope it's not too much terrible technical stuff ...

Jürgen
 

Thanks for the explanation Jürgen.
 
It's all making more sense to me now. I just had a quick "Google" education on Impulse Responses. Pretty amazing stuff. I had no idea that audio could be convolved based on an actual audio recording of a system. I guess that's basically what the Realiser is doing in real-time.
 
I also read through the PDF instructions for the first time and now see what the files are for that you posted in the SVS Demo folder. Pretty cool, but I don't have an ASIO sound card that supports 8 channels.
 
Well, at least I have a Realiser instead.
 
Thanks for all the technical info. I love it.
 
-Darin
 
Aug 13, 2012 at 3:12 PM Post #148 of 404
Quote:
It's really too bad because otherwise the system sounds quite good to my ears (via several of the users you measured).  If you ever get a chance to redo this, it would be nice!
 
Reading Jurgen's posts makes me wish I were an audio engineer and not just a music listener.  


 Yes, Ivan felt REALLY bad. Obviously he is really proud of his home theater and was mortified to find out that it was operating at less than optimal with such an easily fixable problem. On top of that, I drove 2 hours each way to get to his house and do the measurements. He really wants me to come back so I can hear his system in full glory.
 
Someday I hope to make it back there. Not sure when though...
 
Aug 14, 2012 at 1:55 AM Post #149 of 404
Dear JieJie, sorry your professional explianation for me seems a bit of confuse,
 
1, I have Nuendo, and Saffire LE sound card (up to 6 channel), what should I do?
 
2, According to your explaination for foodbar, do I need to install Console VST and Reverberate LE Vst plugin at first and put it in VST plugin root in Nuendo? (I know how to put it in, same as other  VST plug in. )
 
3,If the proceudure is right, then I can use these VST plugin in Nuendo? Which means, I can add any track of music, and select VST plugin, so I can enjoy any PRIRs without open SVS?
 
4, Moreover, if any of the PRIR are out of phase, do you mean you can restore the problem and make it become "normal" ?
 
5, If my understanding were not wrong, do you mean you have sucessfully "transfer" the SVS hardware to the software?
 
Sorry I have too many questions, I will be much appreciated if you can give more explianation :)
 
Aug 14, 2012 at 12:39 PM Post #150 of 404
Hi community,
 
I've answered Jiang1202 by PM to avoid "forum overload" by technical stuff.
 
If anybody works with a daw and requires additional hints, please write me a PM.
 
Darin: these 4 hours are a good investment ...
 
 

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