Left/Right Time Alignment + v200 Hijack

Alright get it here:

http://www.edmi.com.au/dl/Hijackv200+Delayv10.mk2.zImage

It's based on v200 Hijack and 2.0b11 kernel. Mk2 only at the moment I'm afraid. I should be able to do Mk1 soon though. Let me know if you are a Mk1 user.

Look for "Left/Right Time Alignment" in the Hijack menu. Pretty self explanatory really. Adjust the time in 0.1ms increments and it gives you approximate distance in centimetres. When it says 1.0ms Left that means the left channel is delayed by 1.0ms.

There are some definite clicks which I know about when changing the delay. I should be able to fix this, but I wanted to get it out there first.

One thing I have noticed is that since 2.0b11 and running on home power, my RioCar seems to start the VFD dimmer than 100% sometimes. This could be from my messing but I doubt it. Has anyone else seen this? Or could my RioCar be faulty?

Oh and I do everything before Voladj so that might cause some problems. However given the latency in voladj and the maximum of 12ms delay, I doubt you'll have problems.

Hey, do you have a kernel patch available instead? I have a few other customizations in my kernel that I don't want to lose...

Sorry not yet . The eagerness of everyone has caused me to release it as quick as possible.

Also I am kinda new to this patch thing. Can you give me a quick rundown on how to generate the patch? I'm not sure I correctly the applied the voladj and rdsfake patches to the 2.0b11 kernel (one had an error). I have only changed a few sections, so I am going to go back and tidy things a little, so I can generate a nice patch for everyone.

As I understand it I need an unadulterated, 2.0b11 + rdsfake + voladj in a separate directory.

What's the command from there? I assume this should be run from the root of the source tree?

Thanks,

can you make it so that it save the settings for AC and Car power because at home the right speaker is closer and in the car well its left hand drive

Yes Yes, that will all come in time. This is really a test release to make sure that the concept works.

Like I said there are bugs (clicks when adjusting for example) and also deficiencies.

At the moment I just want to hear if it works or not.

Can you make it so I can hear the right channel when I drive to work in the morning and then the left channel (delayed by about 1 hour) when I drive home at night? Oh, for all cumulative tracks too. It might need a bit more buffer space, but it would be cool to be able to hear all the same tracks on the drive home without having to use repeat or a looping playlist.

And maybe we can get an editor made so that we can make our own panning audio & reverb effects to go with the Flancedoor animations.

Think you can whip that up tonight sometime? Ok, maybe I'm getting a bit carried away now.

Bruno

>> (delayed by about 1 hour)

HAHA!!!
That's hilarious...but it makes me need to ask...
You're only at work for about 1 hour??

you people dont want much do ya?

edit:
just downloaded the hack. OMFG it's amazing! Only tried it with headphones and upto 1ms you can head the difference panning to the left or right. Past that the brain gets confused and blurs the image considerably. I imagine it'll be better in the car.

I don't have it running in the car while I'm at work. The drive takes me the hour.

Bruno

So has anyone tried to dial out the delay in a car yet?

hybrid8: what are you trying to say? Have I not done enough for you in the past 2 days? Anything is possible if you really want it (and have enough spare money)

Have I not done enough for you in the past 2 days?

He's just yankin your chain.
10 versions in 2 days? you should be able to surpass hijack by the end of next month!

I tried it out in the car and guess in my excitement i locked the keys in my car. Dammit

Aaah Murray I see where you found me....

I know he was yanking my chain. I guess I didn't reflect that in my reply. Either way this is only the first version. I didn't do the hijack thing. My v10 mean v1.0 which you will catch in the display when you boot.

acurasquirrel: ooh bugger

BTW: I forgot to add the standard disclaimer.

If your empeg blows up because of this hack then well blame yourself for trying. Not trying to be harsh - just stating the bleeding obvious.

well the main thing is, is that it works awesome in my car. Thanks man

I tried it in the car to work today... There was some difference but I couldn't say wether it gave a left/right movement of the music... Do you notice any difference when using high volume, high bass or something like that?

Marius (Escort Cab + Mark II)

Well all I can say is that the channels are definitely delayed from each other so unless those digital time alignment systems do something else (I doubt it) then it should work.

You should be able to close your eyes and feel like you're sitting in the middle of the car. Try setting it to zero delay and put your head over the centre console (probably right in front of your empeg). That's how it should be.

Speaker placement and setup (splits vs coax etc) will make a fairly large difference I would expect.

It may be that my hearing isn't really trained either :-)

Marius (Escort Cab + Mark II)

Bruno, any plans to add this to your HiJack FAQ?

You won't notice it with source material that's mono or has poor stereo imaging. Try it with some nice acoustic music that's well recorded, it'll be more obvious.

Why wouldn't you notice it with mono? Left and right may play the same sound, but the timing can still be different.

Yes, i'll add iit. (and the name's loren, not bruno... heheh.)

Loren, damn, sorry about that! I was just talking about Bruno to another user (Bruno was kind enough to help me set up my AudioGrabber). I swear I knew it was you and was reading the FAQ right before I happened on this thread!

(embarassed - walking to corner)

Make a directory that contains the source code before your edits (let's call it hijack.v200). Make a different directory at the same level that contains the source code after your edits (let's call this one hijack.v200.ta). To be clear, these two directories should be subdirectories of one parent directory, so that they are direct siblings. Make sure that you are in that parent directory so that you can see both source code directories. Now enter the command ``diff -ruN hijack.v200 hijack.v200.ta > ta.patch''. This will create a recursive unified diff that includes brand new files and write it to the file `ta.patch'. (Since it includes brand new files, the new source tree should not contain compiled object files and whatnot. It should be as pristine as possible.) (Also, for the record, mlord uses the diff command ``diff -u --recursive --new-file --exclude=zImage --exclude=config.ini --exclude=.* --exclude=*.patch --exclude=buildit --exclude=defconfig <orig> <new>''. The `--recursive' and `--new-file' options correspond to my `r' and `N' options. The rest is for his convenience and should be fairly obvious.) (Oh -- you'll have to make sure that you're using a GNU diff. If you get an error that the -u option is unknown, go download it. It's much better than anything that a more standard diff can give you.)

Thanks Bitt,

I will do a few fixes and add some things like car/home options and some presets in the next few days and try and get a patch for everyone.

Ok, I've been testing it for quite a while now, in my car. Absolutely great job! I took a song with the singer's voice well placed in the middle of the stereo image, closed my eyes, and started to move it right and left until I centered it right in front of me. Absolutely fantastic! I've been waiting for this for such a long time! Thank you, really! As I said before, this was the only real problem in my car installation, or, at least, the only one i really really cared. Now it is fixed!

Now, trying to be more constructive, I think that yes, if you could eliminate the glitch when changing the delay value it would be perfect. And I also agree very much with the suggestion to separate in car and at home settings. Great idea that about the presets, too. And I would also suggest to add a bar with a slider to give a visual indication of the current cfg. Besides that, it looks simply perfect to me. I did'n find bugs of any sort, and I used it now for a couple of hrs continuously.

Again, thanks!!!

Glad to hear it works

Someone has reported that he had the channel he was delaying would just cut out for some reason. I haven't had it happen, and you haven't either it seems.

1) The glitch will almost definitely disappear (or at least be greatly reduced).

2) Car and home settings are coming. I'm running out of flash storage space though I think. It may have to become an config.ini setting and the player simply remembers where it currently is (Car/Home). It will allow you to adjust it once running - you'd then have to copy the values to the config.ini file later on - I'm not sure (haven't looked) to see if Mark has routines for adding to/editing config files.

3) As for the slider bar, I'm not exactly sure what that would show. Obviously no delay is middle of the bar, but if I delayed the left by 3ms (out of max of 12.7ms) what would it be? I can probably do it, I'm just not enitrely sure what you want or what it would show.

IMHO the slider bar would show the center of audio NOW.
For example, no delay shows
||------------+------------||
and delayed the left channel of e.g. 3ms (so the center for the left seat will move to it):
||--------+---|------------||
or similar.

Ive had a channel completely cut out on me as well

Is it possible to use a popup similar to the fader?

In reply to:

---

Ive had a channel completely cut out on me as well

---

acurasquirrel, you were the person I was talking about.

In reply to:

---

Is it possible to use a popup similar to the fader?

---

Probably not since I think the volume/balance/fader/loudness/beep volume popup stuff is done in the player software not the kernel. Correct me if I'm wrong.

Dont worry its not the kernel its the player. Apparently it wasnt locking into place right all is well now.

No, I had no cut off either, at all. I've been using this for one more day and I renew my total appreciation for the way it works. Fantastic!

Now, as to the slider bar, I was thinking of something like what papinst showed you, but I admit it is a quite controversial way to look at it. What papinst said makes perfectly sense, as long as you are sitting in the middle of the car, or better of the speakers. Now, this whole thing is needed just because you are NOT sitting in the middle of the car. So, I had this idea, which maybe you like.
Assuming you are sitting in the left seat, you'll hear the "center" of the stereo image shifted to the extreme LEFT, since you are closer to the left speaker. So, when NO ADJUSTMENT has been done, the slider bar should look simply like this (just the bar, no slider, and with the two labels Left Seat and Right Seat, as shown.The reason for this is that the slider overlaps with the exremes themselves. See below why):

L. Seat - R. Seat
||----------|----------||

all bright or all dimmed

Ideally, the two extremes of the bar represent the location of the speakers (let's say the doors of your car). The two half of the bar represent the stereo image as perceived from the two front seats. i.e the left half represents the point of "view" of the person sitting on the left seat, and the right half represents the point of view of the person sitting on the right seat, respectively.

Now, when I delay the LEFT channel, I do so just to move the stereo image further from the speaker I am closer to, in this example the LEFT one. So, supposing I delayed the LEFT speaker a little bit, I would have this

L. Seat - R. Seat
||--+-------|----------||

bright - dimmed

If I decided to delay still the LEFT channel some more, I would have this:

L. Seat - R. Seat
||-------+--|----------||

bright - dimmed

(Notice, I imagine the slider never crossing the middle of the bar if not when sitching to the OTHER (RIGHT) channel delay. See below what I mean*.)



If instead I decided to delay the RIGHT channel, I would see something like:

L. Seat - R. Seat
||----------|-------+--||

dimmed - bright

And if I delayed the RIGHT channel more, I would have

L. Seat - R. Seat
||----------|--+-------||

dimmed - bright

*Also, I noticed that if you keep turning the knob, you move from the LEFT maximum delay to RIGHT maximum delay. This is perfectly meaningful in this graphic UI, since it would consist, graphically, in shifting

from ||--------+-|----------|| to ||----------|-+--------|| , i.e. from the situation in which the person sitting on the left seat perceives the center of the stereo image at his right, to the situation in which the person sitting on the right seat perceives the stereo image on his left.

I hope I was at elast a little bit clear...

What do you think?

I'll see what I can do. It will probably be the last thing I fix. I'm trying to get rid of the glitch first, then the presets, then the slider bar.

I am still having issues with generating and applying patches on my home machine which I am trying to set up for development at the moment.

Of course, this is just an idea, it is great already now!

Ok, if i am sitting in the drivers seat(left side) which side do i want the delay on, the speaker that is closer or farther?Also what does the centimeter measurement for:does it mean that speaker is 3.33cm closer than the other or farther?Or does none of this matter and i just adjust till it sounds good.BTW ive only owned the player for 3 weeks and it keeps getting better all the time MIKE

I would think you delay on the speaker closest to you, because that way the sound (theoretically) arrives to your ears at the same time.

Correct - you want to delay the closest speaker.

So sitting in the left hand side of the car you would want to delay the left hand speaker. The distance is just an approximation of the delay times the speed of sound. i.e. 3.33cm is about how far sound will travel in 0.1ms (I took the speed of sound as 1200km/h).

So e.g. if your right speaker is 1.3m away and your left speaker is 0.3m away you would want to move the left out by about 1m. So you would set the delay to 3.0ms to move the left speaker 1m further away.

Crap... I'm gonna have to break out the ol' Trig book to figure out EXACTLY how long it takes the sound to get from the speakers to the ears, as they're not exactly to the left or right of me but pushed 2 feet to the front..... Now HOW's that go?? Sohcahtoa? I think that sounds right... ;8^)

Or you could just use a tape measure.

"Fix it in hardware"

Damn, that just makes ENTIRELY to much sense for me to think of. Heh... Ya know, just when you think you're doing pretty good, you have a total brain-fart.

Oh, and lest I forget, waaaay cool hack...

Or you could just sit in the usual listening position and adjust it to what sounds best... Saves the extra hardware reworking required by the tape measure method.

Looks like it probably won't be 'til the end of the week before I get another release out. Sorry, I have a real job which is taking a lot of time at the moment and I'm still trying to get a good development environment setup.

Hehe, I can't really tell what it's really supposed to sound like. I can only tell it sounds different.

Basically it should sound like the music is right in front of you. Normally it will sound a like the speaker that is closer is slightly louder. A poor mans version of time alignment is using the balance control.

While I'm here can someone tell me a little more about the patches from Mark Lord. His page says apply the Hijack patch on top of the voladj patch on top of the rdsfake patch on top of the clean kernel. It appears that the hijack patch includes both the voladj and rds fake patches. Can someone confirm this for me? It seems Mark has stepped out of the room for the past few days....

Hmmmm.. Ya know, that's true... To get it exactly right, you need to time-delay the closer speaker, AND reduce it's volume a hair to match the volume hitting your ear from the other speaker. Sorry for stating the obvious, but I just never really thought about it.

Actually depending on where you are versus the speaker, off axis or on, you may not want to change the volume. Like was mentioned, you can't science this out. Just play with it until it sounds good. A "pink noise" track or a good song with a single vocalist is ususally the easiest way for me to set something like this up.

Shonky, thank you SO MUCH for starting on this!

I downloaded a whole bunch of free sounds from somewhere, don't really remember where. I put them all on a web page Here.

Here is what is on the page.

Pink Noise - In phase

Pink Noise - Out of phase

Sirrus Tone - In phase

Sirrus Tone - Out of phase

White Noise

Sweep Left

Sweep Right

Cool effect from the end of the Aphex Twin song Windowlicker (looks awesome in Windowshade or Spectrolog visual modes)

The in and Out Of phase sounds are good if you want to see if you wired your speakers the correct way.

BTW Tony, RE: "fix it in hardware". That's hillarious, I was rolling.

Ah, good. Wasn't sure if anyone caught that joke, thanks. I've actually used it before (in similar situations), never got any comments until now.

haha, i used to call my "production group" in college Fix It In Post Productions.

Is it also possible to have a config.ini setup for the Delay.

We could give only 2 lines 1 for the left and 1 for the right :


right=183.2 (in cm)
left=0

And the prog will autocalculate the delay with the distance.
Eventually have a config fot home and one for car.
Yes I need also to setup delay for home ...

Hi Christian, any chance you'll get a kernel patch out soon?

The link is dead. Can email me this so I can implement it into my player?
Dave

I'm definitely getting channel cut out problems. Meaning a channel would have no sound coming out at all.

I've had one lock up occur by spinning the knob very, very fast, the empeg locks up completely and needs to be yanked to fix.

Also, I might be crazy, but the Left and Right are backwards?????? I've tried delaying it to the left -- left hand drive -- and it sounds like ass. Then I delayed it to the right and it sounds centered (???). The build in left/right balance works correctly. But sure what's happening exactly. I will do more testing later.

Calvin

Is the distance values the distance of the delay from the delayed speaker to your ear or the distance the focal position is moved relative to center? I suspect it is the former... but the GUI has me thinking that it is the latter.

Calvin

Yes it appears the server hosting our website has gone out to lunch. I have emailed you a copy Dave. In the meantime can someone else host it for me? Mark Lord appears to have disappeared for a while otherwise I could have it hosted there.

I don't really have time to do a sourceforge site at the moment. I'm struggling for time to add the extra features people want and investigate these bugs. I will try and get some things done today. I am having the day off today, so I'll see what I can get done.

(edit)
Link appears to be working now...

Okay then eternalsun,

acurasquirrel says that his channel cutout problem was due to the sled not being in properly. It appears he (she?) may have been wrong with their diagnosis. I will see if I can reproduce it. Can anyone else?

The distance is the distance the channel is moved away. So if the speaker is 0.3m away physically a delay of 1.0m will put the speaker 1.3m away acoustically.

I don't know if this helps, but since it is working perfectly here I thought I could share what I did.
Without delay, I always heard the left channel louder and "closer" to me, so that the supposedly "centered" singer's voice would sund slightly on my left, and the whole stereo image was distorted towards my left.
SO, I started to delay the left channel (acoustically pushing it away from my position by the amt of cm. indicated on the display) until I clearly heard the singer's voice right in front of me (I did not measure anything, I just closed my eyes to figure out it all better). When I reached this status I could hear the whole stereo image much more clearly. Everything sounds better now, noticeably!

Darn... down again (9:50pm pst 2/18/02)

Ditto on the copy via email if possible.

<<<<pleeeeaaasseeee>>>>

TIA

=o)

[email protected]

Bugger is there anyone who can host it for me? Mark Lord is out of action it seems otherwise that would be an ideal place...

[edit]
try here instead
http://www.uq.net.au/~zzchack/files/Hijackv200+Delayv10.mk2.zImage

WOW!!! Thanks. From BBS to Car in less than one hour. =0)

I am actually looking forward to my morning commute tomorrow.

This hack takes the cake of the coolest and perhaps most useful one yet!

I think that people sometimes forget that the empeg is for music. Don't get me wrong, I apprecieate the Flancedoor editor software, the logo editors, the NAS capabilities, the escher lovers, and emptris, but <sheesh>, who has time to watch this stuff while you are in driving a car?

Thanks for the awesome contribution!

Now if I could just get mlord to work on the auto-vol adjuster to harden the knee, shorten the attack, and set the release to infinity.

cheers,

Lothar

Here 'tis Tony. Should be patched over v200 Hijack patched kernel. You should patch it from the same location as a Hijack. i.e. root directory of a v200 Hijack kernel with patch -p1 <timealign.patch

Individual (car/home) settings are getting there. Haven't decided exactly how to remove the glitch yet.

http://www.uq.net.au/~zzchack/files/timealign.patch

How does this work? I am sorry but I am not a Linux guy so I am a bit lost.

Would it be possible to have a independent patrch to be added to an already hijack-patched kernel, by just using Tony's Logo Editor? I mean: take a standard kernel. Apply the latest HiJack patch (hijack.zimage) with Tony's Logo Editor. Then apply the latest timealign patch (timealign.zimage) still with Tony Logo Editor?

Thank you,

No. The kernel source code must be patched with the HiJack patch, then patched with the time align patch, then compiled to a zImage file then the zImage file uploaded to the player.

Hopefully once Mark returns from whereever he is he can merge the time align code into HiJack and all will be well...

Are you going to be adding an option to slightly (but accurately) lower the volume on the delayed side (I've been following the thread, but I didn't catch any mention of volume adjustment)? With the close proximity of speakers in a car, one of the most noticeable changes to alter the perceived sound stage is volume (balance). I don't normally like playing with balance controls because often they're too rough for fine adjustment. Plus I haven't seen one yet that includes quick-presets. Having your patch presets be able to be called from a Hijack popup would be phenomenal.

Bruno

Beautiful. I'll try the patch out tonight when I get home.

Basically you're asking for a more refined balance function, aren't you? So, do you think the distance of the speaker also creates a perceivable difference in volume? That's interesting. I actually thoight about that, but was wondering whether that would be noticeable at all...
However, since we're here, I'd like that too. Hey this is making empeg even more unique than it already is...

I got it to sound pretty darn centered using a 4.1ms delayed right channel. I'm sitting in the seat on the left.

It doesn't make sense that if I delayed the far speaker on the right it will sound centered, but it does. When I try delaying the left, it sounds like garbage.

For example, YYZ's opening sequence with the bells going around in a circle.... a 4.1ms right delay puts the center of that circle on my head. If I delay the left channel it instantly sounds like garbage.

Calvin

I get channel cutout by twirling the knob to the far ends of the delay scale. Around the moment where the right switches to left and visa versa... there's a place that cuts out. I'm not sure if there is a phased relationship between the speaker causing it to *sound* like nothing, but when I lean in on my tweeter I hear nothing. When I reduce the delay to reasonable levels it sounds super duper.

Calvin

I give up. That doesn't make sense to me either, and I did not get that on mine!

eternalsun:

I twirled the life out of it last night but couldn't get it to cut out. Also are you sure you have your left and right channels the right way around. You're the only who seems to have the left/right problem. I am quite certain I have left and right correct - I checked it about three times because there are few places where it could get swapped in my code.

As for volume adjustment that is a lot trickier than it sounds. At the moment I am merely delaying samples. Reducing volume as in the voladj code is a fair bit more difficult. I could possibly latch onto some of the voladj stuff and do it there assuming I can attack one channel only.

Suggestion: Try the empeg's balance control. Does it work properly for you?

Bruno

eternalsun:

>>>It doesn't make sense that if I delayed the far speaker on the right it will sound centered, but it does. When I try delaying the left, it sounds like garbage.<<<

Sure it makes sense. I have the same setup in my Jeep. The reason why it makes sense is because the speaker on the right is on-axis with your ear. The sound will actually reach your ear faster from the right speaker because unlike the transducer on the left which is off-axis of your head, it does not have to bounce off the right side of the car before reaching your ear. Make sense?

As long as it sounds good! Stick with it.

lothar

any news on a MK1 version ?

Well I have the patch out now. If that's not your scene let me see what I can do...

Now you can get a Mk1 version...

WARNING WARNING WARNING
I do not have a Mk1 so I have not tried this at all. It may not even boot. At times while I was developing on a Mk2 I had issues where the kernel was way broken and the unit wouldn't boot properly. I was able to get out of this each time with little hassle using the standard upgrade program. So don't complain if it breaks your Mk1. If it does an upgrade will probably rescue you.
END WARNING

Get it here

Actually, I could use the most basic installation help... I have it downloaded. I give it a ".upgrade" extension. Rio Upgrade Wizard tells me it's corrupt. I can build PC's with my eyes closed, but this is getting to me... I know it's something dumb, anyone point it out to me?

Use Tony's Logo Editor to send it to the player.

Bruno

OK,

It's not an upgrade. It's a new kernel. An upgrade includes things like a ramdisk image, player software etc. It needs to be applied using the download.c program or upload included in the logoedit package by Tony Fabris.

Go here for a description of hijack and a link to the logoedit package.

Then run:
upload.exe <patch file> 10000 <com port>

Where <patch file> is the .zImage file and <comport> is just a number i.e. 1, 2 etc. There is no need to rename the file.

The player must be on the AC power supply and you need the supplied serial cable connected to the unit.

HTH

Or you could try the FAQ

Click here

I want to be like Mr Fabris...

There's only one way - never sleep! Monitor all threads 24 hours a day and type faster than any of the old hands. Otherwise they'll win

im getting pretty damn good at doing that.. just start typing random pointless post like this and you will be up to old hand in no time

Naw... that would just be silly.

Got it, actually was quite easy. I misunderstood it to be attached to the whole program, not just the hijack.

IT WORKS! You're so cool! Thank you! I don't think you need to change a thing. My driver seat is on the left, and I have the left delayed approximately 40cm, did it by ear to get there. Turns out that eyeballing it that is actually the path length difference between the speakers.

Hell yeah!

I had previously offered $50 for getting this done. Where do you want it sent?

That's very much appreciated but I think that you should be giving at the very least half of that to Mark Lord. Without hijack, it wouldn't have been as easy for me. Particularly - there wouldn't be much of an interface to set it up.

I think Sven (smu) made an upgrade file creator/extractor, to turn raw flash images into upload files with control sections and checksums. (I'll need to find it myself, if I want my Gimp logo-editor to read and write upgrade files)

Well, how about I buy everyone a beer next time we get together

The mod works perfectly for me, I was playing all sorts of things this morning on the way to work to experiment with it. Nothing funky, just a nice centered sound. I love it. Now I just need to set my EQ and we're golden.

It'll be a fair cab ride from Brisbane (Australia) back to Minnesota

Got back from vacation.

Yes, I mentioned in a prior post that the balance controls work correctly but the delay stuff seems backwards. That's the reason why I say it doesn't make sense. Just in case, here is how the balance control works. When I set it up for maximum left (bars on the left, no bars on the right side of center) sound comes from the left, and no sound comes from the right.

When I use the delay... it works in the opposite direction!

Calvin

I'll play with it some more when I get the chance. The strange thing is, like I said, I'm sitting on the left side of the car, and my perception of centered is 4.1ms delayed right. If I put 4.1ms delayed left, it doesn't sound correct or centered at all.

Like I said before, my balance controls work perfectly.

Calvin

U sure you don't have your outputs reversed??? Or the wires at the amp? I hate to even ask that but... The simplest solution is often the best one.

I have another suggestion for trying to adjust the delay by ear. Going for a perfectly centered image is pretty difficult when you aren't equidistant from the speakers - especially in the tight confines of a car. Arrival time is only one of the factors. You also have amplitude differences and all kinds indirect sound reflecting off your windows.

Instead of going for a centered image try to find the delay where the image smears the least. Find a track with a strong and fairly isolated center image. Human voice is the best because our ears are evolved to hear differences in human voice very well. (I used Joni Mitchell.) Now close your eyes and focus on the voice while moving the delay around. Get a feel for how it changes. Try to find a point where the image seems the most narrow and focused. It's hard to explain but as you move the delay left and right you should be able to hear the image drag and smear in each direction as difference in arrival times becomes greater. With the correct delay the image won't necessarily be centered left/right but it should sound the tightest and most focused. And remember that the perceptual shift will be in the opposite direction as the delay. (i.e. as you turn the knob left and delay the left speaker the sound will shift towards the right because it will be arriving sooner from the right)

I adjusted it by ear first and was very pleased with myself when I got the tape measure and discovered I was spot on.

-Dylan

Shonky, thank you so much! This is an awesome hack. The difference in sound quality is tremendous. I've always been unsatisfied with the imaging of my system and this helped a lot.

The hope for user enhancements like this and, of course, Mark Lord's great Hijack kernel is one of the primary reasons I bought the Empeg. I'm so happy to see skilled people taking advantage of the flexibility of the platform.

-Dylan

Okay, time is running out on this one.

I'd still like to see this stay in Hijack, but the code does need to be tightened up some. Have a look at it, please.

-ml

I'm absolutely certain. My balance controls work correctly. When I play audio test CD's, left and right channels come out correct. When the balance is adjusted al the way to the left, there is no sound coming from the right side. Visa versa. When I adjust the delay, it is backwards. I am sitting physically on the left, and adjustments 4ms left will place the center point of the sound stage on the far right side of the car onto the corner of the dash. 4.1ms to the right will place the soundstage centered perfectly in front of me (on the left side of the car). I went through the rounds *again* yesterday and I can confirm that this is the case. If I adjust any further to the left, the sound smears all over the place and sounds like complete garbage.

Is there anyone in the south bay that wants to bear witness to this?

Calvin

Remember that the given acoustics of a car will vary. I would guess that in some cars, the delay would need to be adjusted one way, and in other cars it would need to be adjusted the other way.

Depends entirely on speakers, speaker locations, and acoustic reflections I think.

That's my gut feeling as to what is happening. I PM'd Shonky as to such. I would like a witness so I can feel like I am not crazy. ;-)

Calvin

Have you looked into volume adjustment yet? I just played with your adjustment on the way home tonight and I'm quite impressed. Of course now I also have to make slight adjustments to my front/rear gain (starting to hear too much from the rear).

Any progress on preset selection? This really needs a quick way to toggle through two or three presets (pluss OFF) without going into the hijack menu.

Bruno

This is the way it is supposed to work. And... the left right setting DOES make sense, even though someone mentioned in a previous post in this thread cited the contrary. Tony is correct - YMMV - "as long as it sounds good" I say.

regards

I'm working on the CPU usage issue and the glitch at the moment. Presets are a little way off yet, I think.

Sorry, I just have a lot of normal work on at the moment.

Mark,
I'll try and have something to you in the next couple of days. Is that OK?

>I'll try and have something to you in the next couple of days

Sounds good to me.

Cheers

I messed with the L/R delay a little more today and noticed that in my car, I need to move it in the opposite direction as I do when listening on headphones. And my car is not wired backwards (balance is still correct), it's just that my soundstage isn't particularly distinct in my setup (I only have door speakers) and the rear speakers are louder than they should be for proper soundstaging. It's all about reflections etc...

Oh Hell yeah! How did I miss this thread before now.... I am very thankful you implemented this!

This was the only thing I missed when I switched to the EMPEG. This is one of the features I wanted so bad that I bought a used external pocessor to do the same thing..... guess I can uninstall that now.

This has made my day!

Anyone want to buy an Alpine 6 channel phase processor? Guess not on this forum .

Wel, in the end, that's not really a problem, I think. Just rotate the knob untill you hear the center of the stereo image right in front of you, and that's it. As Tony said, maybe surfaces, material, shape and speaker location in your car interiors are such that you need to delay the speaker further from you. Weird, but I thnk in theory it is possible. One more reason to use this feature, I'd say...

you might check to make certain that your speakers are wired in phase as well...
--
sancho

A reduction in volume as appropriate for the set distance should also help. A time delay only is not sufficient to properly tune the soundstage. it certainly works better for some songs than others.

It's mostly suited to center non-continuous tones that exist at the same level on both L & R channels. It doesn't work well for in-sync tones of a different pitch, nor for continuous tones. For example, using a long test tone, this patch shouldn't affect the perceived soundstage.

The end result of applying delay only, is that you have sound sources that are equidistant, except the one with the delay has a perceptually louder volume. It's similar to having a pair of loudspeakers each 10 feet away from you with the balance shifted to the left.A reduction in volume as appropriate for the set distance should also help. A time delay only is not sufficient to properly tune the soundstage. it certainly works better for some songs than others.

It's mostly suited to center non-continuous tones that exist at the same level on both L & R channels. It doesn't work well for in-sync tones of a different pitch, nor for continuous tones. For example, using a long test tone, this patch shouldn't affect the perceived soundstage.

Bruno

Is it possible to compensate this volume using the balance left / right.

When i set up the delay patch I noticed that the closer speaker (left) was louder that the right.

I changed the balance to right until I had a 'perfect' sound picture.

Now that rocks with my AC/DC's Hard as a Rock song ...

They're in phase. I go through a tuning CD every 6 months or so.

Calvin

You are totally correct Tony!

When I am using headphones, if I set 4.1ms of delay to the right, the soundstage moves to the right. If I set 4.1ms of delay to the left, the soundstage moves distinctly to the left.

In the car, moving 4.1ms of delay to the right causes the soundstage to move to the left. (!!!!!!) I'm not crazy!!!

Calvin

Your headphone scenario is broken. What you just described for IN-CAR is the correct behaviour. Did you just describe them backwards? Because this is the opposite of what I thought you described before.

Bruno

Sure, you can use balance to do the volume adjustment. But using balance is doing it by ear. The amount of reduction in volume per click doesn't translate to a specific distance. Plus the fact you now have to set up two controls. I really want this all taken care of in one shot so it's easy to turn it ON/OFF and well as cycle through at least two presets (one for driver the other for passenger).

Bruno

Consider this, if you haven't done it. You sit on the left side of the car. Your left speaker is something like 2' closer to you than the right speaker. Punch up into the empeg a left delay of approximately 50cm. Now put in a nice vocal CD and see if it doesn't give you a centered image.

In my experience with my old head deck, with a built in DSP, varying the image just "a little" left or right was very confusing. But when you really cranked on it, out of nowhere, there it was - the singer right in front of you.

I have a 3rd gen Eclipse, sonically not all that different from yours or any other small car really, and at about 41.some cm it's a dead on image right in front of me.

Sure the standard balance control is fine enough to this purpose? Did you try? I agree that changing volume is exactly what balance does, but as I think you were saying before (correct me if I am wrong) the balance control is too imprecise to do that properly... ? Anyway, for some reason I never noticed a difference in volume, even though it should be there in theory. I'll try to play with the balance too...

I would like to know if the Delay Patch is apllied for Front Speakers only or if it could be implemented for the Rear ?

At this time I don't have rear speakers but in the near future I will have.

Maybe is it not necessary ?

It is applied to the channels. So both front-left and rear-left speakerts will be delayed if you delay the left channel. I think it was discussed before that fron-rear delaying is not currently possible from the empeg sw, since it only outputs left and right (2 channels) and not front-left, rear-left, front-right, rear-right (4 channels). It's a hardware "problem", not a software one.


I have to say, though, that with just the current function my car installation sounds amazingly well... I honestly do not know whether I would need and benefit from anything like front/rear delay. I'm just assuming, now, I admint I should at least try. The fact is that I could HEAR the problem with my stereo image before the current patch was made. Now it does seem perfect, I do not hear any problem.
Ehm... Ok, I just realized I do NOT have rear speakers, just a sub. Ok, I'll go to lunch. You guys stop laughing...

But the distance LeftHear/Left Front Speaker is not the same that distance LeftHear/ Left Rear Speaker.

So if the patch is applied to chanel left or right, delay for left rear channel is almost all installs upper value that for front so why even apply it.

Ah, you are telling me that we cannot do else that delay only left or right channel ...


I remove my question !!!!!

OK, taym is perfectly correct. It is a hardware thing that prevents us delaying all four channels individually. If you think the patch is pointless then you don't have to use it.

Also rear speakers shouldn't be used for stereo imaging in my opinion. They should be used for "rear fill" only. I believe in the theory that the rear speakers should be faded out so that they're just not noticeable.

I agree that if you can distinctly hear the rear speakers, they are too loud.

Having the fronts and rears together on the same amount of delay is very nice, obviously better than if it did the fronts only. However (and I know we are hardware limited), delaying the rears seperately compared to the fronts is also nice. Where the left / right delay sits you in front of the stage, as opposed to the left or right side of it, changing the front / rear delay brings you towards and away from the stage. It can make it feel like it is shrinking way out in front of you, or that you are almost right on the stage itself.

This could be done with a variety of aftermarket components, for relatively cheap you could wire in a guitar pedal, if you didn't mind the labor involved actually installing it and converting it for 12V use.

The balance control is very imprecise. My alpine had very fine graduations from click to click, the empeg is very brutish in this regard.

Calvin

I'm pretty certain I'm describing my situation pretty consistently.

I am sitting on the left side of the car. Left hand drive.

If I adjust the *balance* controls far left, the right speakers emit no sound.

If I adjust the *balance* controls far right, the left speakers emit no sound.

If I adjust the time delay to the right, the sound stage moves to the left.

If i adjust the time delay to the left, the sound stage sounds like garbage.

I am pretty sure I did not describe the situation any other way.

I discovered this morning that my patch cables (home) was wired up backwards (!!). I swapped the patch cables to the correct configuration and now even the headphone test duplicates the above described behavior. If I adjust the delay to the right, the soundstage center moves to the left.

Calvin

For me, my home patch cables were not backwards (my balance works correctly for both home and car), but my perceived soundstage changes differently in the car due to its speaker locations, the car interior reflections, and the interaction between the rear and front speakers.

I just asked cos I dont have rear speakers at this time but I wanted to know what can be the sound with this patch.

How can youi rear fill if the delay is aslo applied to the rear speaker ?

The DSP cannot change the delay between front and rear.

The rear speakers are an exact copy of the front speakers. You can EQ the rears differently from the fronts, but that's about it.

You can only change the left-right delay in software.

Well, now that it's consistent, it doesn't make my head scratching any less puzzling. If the interaction of the speakers is so F$*%d up that location cues are ass backwards, why doesn't that mess up the sound staging entirely? Think about that.

Calvin

My sound stage in my car has always sucked.

My soundstaging is getting to be pretty reasonable. Not anywhere as good as the home setup, but instrument placement is coming around to be pretty darn precise. This is based on the instrument location graphs in the IASCA booklet/CD.

Calvin "puzzle.."

Your only "problem" is that you didn't realise it was working correctly. Everything you described in your recent message is EXACTLY how everything should work. For both balance and the delay.

Applying the delay to ONE SIDE, casues the sound stage to move to THE OTHER SIDE. So any delay to the LEFT should move the sound stage to the RIGHT. Just as you described.

Bruno

Right, that's how it should be. If you delay the right side, it's like moving the right speaker AWAY from you, so your stereo image center moves to the LEFT.

And vice versa.

Ok, given that, the visual paradigm used in the GUI for delay is the confusing point then. If you have an interface with a |-----------I-----------| -- the middle point is "center" and when you move the bar left |--------===I-----------| then it implies something is moving to the left. DItto for the right. This makes sense in the balance widget. It works in the opposite manner in the delay widget.

Calvin

That explains it. You were using the original hack, right? I've been using the implementation in Hijack without a bar and it made perfect sense. It just says "left" or "right" next to the delay time. If you delay one side, you know the image is moving toward the other.

The graph thing is hard ti make correctly for everyone. Having no graph is probably less confusing. Otherwise, the opposite of what you described would better indicate which way the image is being moved.

Bruno

Ok, wait, now I am using 221 by MLord and I could not see any bar. However, the wording is quite confusing in v 221. It says, for example,

Shift 0.4 msec LEFT

Mark, what does this mean? I suppose (and also it sounds as) that means that the LEFT channel is delayed by 0.4 msec. So WHAT exactly is being shifted LEFT, as the UI says? The left speaker is the only thing being shifted "virtually" LEFT in the "SPACE", BUT the stereo image center is being shifted RIGHT.
Mark, consider that when no correction is applied, if you are sitting on the LEFT seat, you are in a situation where the center of the stereo image is on your left (because you're closer to the left speaker than to the right one), and by delaying the left channel you move the center to your right until it is right in front of you.
So, I would use the word "DELAY" rather then "SHIFT", which I find extremely confusing.

Also, as to the bar in the GUI, allow me to suggest again what I said in a previous post of mine, in this same thread, posted on Feb 17th . I still thing that is the best way.

>Shift 0.4 msec LEFT
>Mark, what does this mean?

It means "shift the sound .4 milli-seconds to the left.
So, the sound centre will appear to move left.

Got a better wording for that line for me? I found the original incarnation incomprehensible (to me), so I just threw that in quickly before release.

Actually, I think the next step is to use a slider (similar to LR balance), and dispense with the numbers entirely.

Cheers

I would keep the distance number, as that is useful if you are up for actually measuring your distance from the center.. Right? The 0.4 millisecond number is a little less understandable...

Please don't get rid of numbers, after all even the volume slider has a dB number displayed.

Ok Mark, sorry to bother but I am afraid I am having listening problems here.
My question simply is:

When the display says

SHIFT 0.4 msec LEFT

which channel is being delayed?

The right channel, is that correct?

Mlord, I actually find this wording easy to use. It's the soundstage moving left or right that I picture in my mind while I'm making the adjustment.

> When the display says SHIFT 0.4 msec LEFT
>which channel is being delayed?

That's not relevant, really. The sound should appear to be centered more to the LEFT in this case. The end result is relevant, not the means. To do this, the software can either delay one channel, or speed up the other channel.

I guess, to shift the centre to the left, it must be delaying the right channel, or speeding up the left channel.

-ml

Well, Mark, the means is definitely relevant if for some reason you can't hear the result clearly. My point is that for some reason I could not understand clearly where the center was being moved, and the very relevant piece of information I asked was really helping me in figuring out what was going wrong. And since the UI had changed I had doubts about my understanding of it. So, thank you for the clarification.

As to your interesting lesson on logic and moral, means and results, I thank you but that was not relevant, really

Also, hoping to do something nice, I'll answer your guess: yes, in order to shift the the center of the stereo image to the left, you must delay the right channel versus the left one, which is the same as speeding up the left channel versus the right, obviously, but that was not at all the point.

Commands imply means, settings imply results. IE, if you configure something to shift the soundstage 30 cm to the left, you don't care how it actually does the shifting, you are only interested in the end result. However, if you are performing a command, you would have it delay the right channel 3msec or something.. The context is important in this situation, which is why I think some people are being confused..

we need nice graphics of a left speaker and a right speaker on the display. And cranking the numbers should show either the centerpoint moving relative to the speakers or the speakers themselves moving around or something, to show clearly what is really happening.

I just upgraded my hijack to version 224 and the left and right seems to be working on my headphones!!!!!!! I'm so jazzed, i can't wait to try this in the car. The weird thing is when I went into the delay menu, my usual setting of 4.1ms RIGHT was flippd to 4.1ms LEFT after the hijack upgrade. (?????)

I was running one of the very early versions of the delay code before and maybe it was backwards? ?

Calvin

If you remove the numbers you are killing the interface. The numbers and what was written in the first version, were meaningful and accurate. The shift thing makes no sense if you've left the actual performance of the function the same. In the first versions, applying a delay to the left would shift the soundstage RIGHT. If you've just reworded it, then you've broken the status display.

Bruno

In reply to:

---

to do this, the software can either delay one channel, or speed up the other channel

---

How is it possible to speed up sound?(unless you own a time machine)

The music is decoded faster than real-time. But in the end, six of one, half dozen of the other... To the listener you don't care when things are happening internally, so long as one side comes before the other by the appropriate shifted time.

Bruno

No, he didn't just reword it. It is actually moving the soundstage as the ui says, so when shifting LEFT you are actually applying a delay on the right channel. I got confused too since for some reason in car I could not hear clearly what was happening (guess it depends on the particular mp3 i was listening to). At home it sounded correct, as the UI says. However, I too found the original wording more clear, but I guess that's just a personal thing...

Mark is Back !!!

I messed up in my earlier posts. The fact that nobody noticed (or didn't say anything) shows how confusing the terminology can be. On my drive home tonight I smacked myself in the forehead and gave a Homer Simpson "Doh!"

I accidentally used the word "soundstage" as some other people had mentioned when describing how the L/R was working (and how it was working correctly). The fact is that even with a delay, if you want to look at the interface logically, it is actually your Virtual Listening Position that is changing.

So a delay to the left, moves the "perceived" soundstage to the left, but moves your virtual listening position to the right. That's where my goof in word choice was. And that's why some people were hearing things shift to what they thought was the incorrect side.

While driving I also thought of something that may be able to work as an easy interface/description:

Actual Listener Position:
|-----||==>|----------|
Virtual Shift +20cm Right

There we go. The slider is used to set where the listener is sitting. If you are left from center, you move it to the left. If you are right, you move it to the right. This is where the delay will be applied. It starts centered, so in the example above, the user has moved it a few posoitions to the LEFT. The arrow shows the Virtual shift direction. The line below shows the effect of the delay. A delay to the left, causes a virtual shift in sitting position of X cm to the right.

Anyone else find the above more straight forward that everything else we've been talking about?

Bruno

Creative does the same sort of thing in the positional sound configuration of their Live! cards... You have the listener at the center, and position the various sound sources around the 'soundstage'.. So when I think of shifting a sound to the left, I think that it will sound like it's left of wherever it sounded before.. As I'm to the left of the center of the speakers in the car, I would expect it to sound more centered to me.. I care not about the delay or whatever magic is used to make it work..

Mmm.. dunno. I think the less geeky user might just expect it to work similar to a left/right "balance" slider, moving the sound rather than the user (because that's what it really does appear to do).

Or at least that's how I expect it work. But I'm not as geeky as most of this crowd.

Possibly we are all aware when shifting, that LHD and RHD vehicles are catered for. When a car driver adjusts this setting they need to either know about accoustics and/or make some assumption on the programmer's perspective on the problem/solution. One easy to percieve situation for most people must surely be the (intuitive but subconcious) assumption that LHD cars need a left delay, RHD cars need a right delay? As a driver (and 1st time user) I tried to second guess the programmer in terms of whether 'Left Shift' meant move me left or whether I drove on the LHS of the car to start with - sure, it's obvious when you know the programmer's viewpoint but not so obvious as the 'consumer'.

What about, when shifting the centre to the left the display reminds us which side of the care we are (likely) occupying i.e. the display would read (for LHD):
Shift: 1.0 msec left
Distance: 33.30cm [LHD]

... try to think in terms of the driver when you read this (aren't car player settings driver centric after all?) e.g. [LHD] reminds us of the driver position when adjusting. If we go right, past zero, the display would show:

Shift: 1.0 msec right
Distance: 33.30cm [RHD]

I.e. the [LHD]/[RHD] text would automatically switch according to the driver's position in the car. I think there's space on the display to accomodate this.

Rue