Try Ambiophonics with your speakers

[fcserei]

Originally posted by poldus
I already have a yss901 working with analogue in/out and the physical barrier has been removed.

I am currently experimenting with the separation/angle of the stereo dipole to achieve the widest image.

I think I will build a dipole where the left and right drivers´ rims converge at the center of the box (minimum possible distance between them) and facing slightly outwards (convex baffle).
So far I´m convinced this widens the image the most.

I would like to know if this matches others´ experiences.

On a different note, I have some digital background noise that I´m trying to remove (by hit-or-miss trials since I have no training in electronics whatsoever). I just found the quietest spots on the board so far to apply external analog and digital 5V but I´m looking to improving this area.

I will soon attempt digital in/out with another chip (I bought ten from China)

I am very, very excited over my achievements so far !

The U board of the Sony is full of very noisy secondary power supplies. Best to remove them all. Also, the DAC in the YSS is very noisy, especially if you are using the 15 or 10 deg setup where you need 2 or 3 bit shift for processing overhead.
For the digital only mode I found the YSS is the easiest to interface in the YAMAHA DSP mode if your receiver supports that. I had a quick look at the docs you sent, and looks like they support it only in SW control mode, not in hardwired setup.
In that case you can try the 64fs I2s on the receiver and you can delay the data line with a shift register clocked by negBCLK.

[fcserei]

Originally posted by eStatic


Well that's a bug not a feature as far as I can tell. When one pans a signal across the sound stage the volume should not change perceptibly, but it does. It looks like I will be seeing Robin Miller in the first part of May. I'll definitely ask him about this.

It depends. Neither the RACE not the inverse HRTF based XTCs has FR problem if you calculate the signal at the ear for different angles according to the models they use. The question is wether the model they use is correct.


In my experience inverse HRTF based XTC is much more believable than the RACE. I mean panning in RACE can match closely panning in stereo. Panning with XTC using inverse HRTF sounds much closer to that, when somebody actually moves a single source in front of you.

[durwood]

Originally posted by fcserei
Panning with XTC using inverse HRTF sounds much closer to that, when somebody actually moves a single source in front of you.

Do you mean the attenuation that estatic is talking about is normal and should happen? Maybe I'm not udnerstanding what he means plus I'm still getting used to picking out the differences between ambiosonics, ambiophonics and other playback methods vs stereo. I've got a few different XTC cancellation VST plugins and they all seem to do different things. Part of me thinks it has to do with the stereo recording as well and how it was mic'ed or engineered.

estatic-where did you get your model of RACE?

This is the most recent one I have found that describes the techinical aspect of how RACE works. Nothing on the Choueiri XTC though. I actually prefer the Choueiri over RACE.

http://www.ambiophonics.org/files/RA...M-RACE_rev.pdf

EDIT: Just realized there is an updated impulse for the Choueiri XTC. This is fairly new since the last month or two. It would be nice if the link actually worked.

fcserei-do you have any more info on how they made the demos at ISVR? I'd like to experiment with the inverse HRTF and XTC at the same time but the info on OSD is very scarce.

[eStatic]

Originally posted by durwood
. Part of me thinks it has to do with the stereo recording as well and how it was mic'ed or engineered.

That is correct.

Originally posted by durwood
estatic-where did you get your model of RACE?

here
http://electro-music.com/forum/viewt...&postorder=asc

[mjensen]

The Choueiri XTC file exist, but the link is incorrect. The correct link should be http://www.ambiophonics.org/files/Ch...3_46rmC2x2.wav

[durwood]

Originally posted by mjensen
The Choueiri XTC file exist, but the link is incorrect. The correct link should be http://www.ambiophonics.org/files/Ch...3_46rmC2x2.wav

Thanks.

Estatic, check that paper I linked. They added extra filtering compared to the diagram shown at electromusic.

Also, there was work done with this years ago at doom9.org.

Has anyone used this VST?

V.I. Stereo to 5.1

http://forum.doom9.org/showthread.php?s=&threadid=85446

[eStatic]

Originally posted by durwood

Estatic, check that paper I linked. They added extra filtering compared to the diagram shown at electromusic.

Thanks, I handn't noticed that. I think the missing band exclusion filter was a missprint. It was in an earily version that had been posted. I've pointed out the problem to Howard.

The one I implemented matches the one for which you supplied a link except the LPs were at 300. I have some doubt as to which LP frequency is correct, 300 or 250 I'll check into that.

[durwood]

I think it would depend on how steep the filters were, these are FIR filters I assume? I wonder if this is just guesswork/trial and error or not.

BTW, someone at electro-music mentioned Ralph as coining the term "ambiophonics" and I know he called it that in his book, but I found an AES paper dated as far back as 1960 where the term was suggested and the author further went on to discuss how they currently did not have the processing power to perform such XTC cancelation, but in future it might be available. Well...the future is here. I'm not sure if he was the first to use that term, but these concepts were actually around in the infant stages of stereo.

There are other new playback methods emerging too, but it's all rather in it's early years.

[poldus]

fcserei: thanks again for your help.

I would appreciate some further advice regarding the noise in analog mode:
I removed the chips before and after the yss901 analog in/out, as well as two supply regulator IC´s.
Please check in the attached file where I´m feeding the board with my external 5V supply.

Bypassing IC404 and 412 ( but keeping them on the board) is noisier than tapping before them so these have not been removed. I can´t remove them without destroying them so I would only do so if I was really positive I was not to regret the move.

With these bypassed, or if removed, the same +5V line is fed to both DVDD and AVDD. Would that be sound practice?

What about using two independent power supplies for analog and digital (I would have to lift the AVSS leg and connect one of the grounds there). Would that cure the problem?

[poldus]

Well, I´ve answered my own questions. First I removed IC´s 404 and 412 (and destroyed them in the process) and the noise was much louder. I went for broke and lifted all DVSS legs to apply separate 5V lines to analog and digital but there is no music coming out. All I can do now is reconnect those DVSS legs and have someone tell me what I need between the analog and digital supplies that will make it work without noise.