Topic: Sound Devices 744t inverted phase issues

[baustin]

I haven't been able to find a thread specifically devoted to this topic. Has anybody gotten to the bottom of this?

This is the only thread I've seen hitting on this subject ( http://taperssection.com/index.php?topic=49528.0 ) but I haven't found a suitable answer. Maybe all I need is a physics refresher course.

Anyway, here's where I stand...

I just made my first 4 channel recordings (2 sets of AUD mics) with my 744t, firmware 1.60. 4 mono files.

Source 01 - Neumann u89i>EAA-PSP2>744t (analog into channels 1+2)
Source 02 - Schoeps mk41>KC-5>CMC6>V3>digi-in>Tascam HD-P2>744t (digital into channels 3+4)

Now I realize this is a bit of a different situation from the above thread started by wboswell (2 very different brands of mics and the Tascam), but the sources synch up identically, except that they are out of phase.

This raises a few questions...

-Which source is out of phase? Theoretically, the Tascam and 744t should only be recording a digital source. If this is correct, does this mean that every 2 channel recording (into channels 1+2) made by a 744t is out of phase?

-Could the V3 have inverted phasing issues like the AD2K+?

-Could synching the Word Clock of the 744t to the Word Clock of the V3 help?


Maybe some of the brillant minds here can explain the whole multitrack phasing thing....


-Bryan

[jeromejello]

-Could synching the Word Clock of the 744t to the Word Clock of the V3 help?


Maybe some of the brillant minds here can explain the whole multitrack phasing thing....


-Bryan

i dont know anything, but if there is a word clock out on the v3 that would be the reference needed for the 744t to sync up i would think.

[chun]

If you use any external digital in - then the 744 will sync to THAT word clock.....

[fsulloway]

Brian- Check out the pic that Damon posted of the wave files in that same thread. I could be wrong but didn't one of the updates for the 744 fix the phasing issue?

[baustin]

Brian- Check out the pic that Damon posted of the wave files in that same thread. I could be wrong but didn't one of the updates for the 744 fix the phasing issue?

I believe that the 2nd pic he posted were files he inverted himself. At least that's what I got.

Also, I just got the 744t this past Tuesday (3/14) so it has the latest firmware.

-B

PS- I'm in NYC right now and I PROMISE I'll send those Tishamingo DAT's as soon as I get home! 

[Dr.FOB]

I have noticed this problem when running V3>digi>744 also.
I queried some other v3>744 users to check into this.

I'm going to assume that the phase of the mic>744 is correct and that the V3 is providing an inverted digi output.
That's how I've been mixing my matrix renderings to date.

[baustin]

If you use any external digital in - then the 744 will sync to THAT word clock.....

Chun,

Is there a difference between synching to the sample/bit rate and synching to the word clock? I honestly don't know.

I was just thinking about this because I remember reading about people synching V3's with broken AD1000's. I think I read that they were able to get AD1000's with dead crystals to work like new. Completely different animal, but it just had me curious.

-B

[baustin]

I have noticed this problem when running V3>digi>744 also.
I queried some other v3>744 users to check into this.

I'm going to assume that the phase of the mic>744 is correct and that the V3 is providing an inverted digi output.
That's how I've been mixing my matrix renderings to date.

Alright....

So this is still an issue and we need to get to the bottom of it.

Chun, I see you have multiple pairs of mics as well as a MiniMe. Maybe you could do some testing when you've got a second. It'd be interesting to see what results an A/D other than a V3 produces.

-B

[Dr.FOB]

Chun, I see you have multiple pairs of mics as well as a MiniMe. Maybe you could do some testing when you've got a second. It'd be interesting to see what results an A/D other than a V3 produces.

John and I both ran multi mic rigs in Philly.  He ran mic direct and mini-me digi in and can check those for us.
I ran V3>line and V3>digi (2 V3's) so that comp won't help.

I will try later a V3>line and V3>digi from the same V3 and see if the digi is inverted there with respect to it's own analog output...

[cleantone]

couple questions... (never used a 744 so bare with me)

Have you imported to a DAW to notice the phase issue?

If so do each of the stereo recordings (you had 2 stereo pairs right?) sounds okay on thier own? Meaning is it only when you combine them that you hear a phase issue.

I think I'm right about this:

suppose you look at each track on its own. If you find something with a lot of low end (big waveforms) you should see the beginning of the waveform go positive before negitive (above the 0 line not below)

This should tell you if any of them are reversed polarity. I assume you mean reversed polarity when your talking about phase here. This is an easy fix.

I have more once you answer this...

EDIT:

I just read some of the thread that was linked here. Heath goes into what I was thinking. I assume it is the same problem.

[baustin]

I will try later a V3>line and V3>digi from the same V3 and see if the digi is inverted there with respect to it's own analog output...

This would be perfect.

Regardless, has anybody tried this just to do a V3 A/D vs. 744t A/D comparison. Actually, that's a stupid question. I'm sure it has.

Anyway, I'm sure V3>744t analog and digital should shed some light.

-B

[cleantone]

Assuming this is the problem (polarity reversed) to tell which one to "fix" look at the compression and rarefaction of a low frequency note. Low because the waveform is bigger. Doesn't have to be low of course. Anyway you in the proper one you should see compression (+) before rarefaction (-). Look at this picture.



I find a lot of the time the highest amplitude peak on a single seciton (snare hit, single note etc...) is compression. That might help you as well in identifying the proper track to fix.

As Heath said in the thread linked in the first post when the kick drum is hit your speaker should go outward and not inward. This can be a little hard to distinguish in some cases though. That is another way of making sure you fix the proper channels.

[baustin]

As Heath said in the thread linked in the first post when the kick drum is hit your speaker should go outward and not inward. This can be a little hard to distinguish in some cases though. That is another way of making sure you fix the proper channels.

Fixing the phase in Wavelab is possible, but is a pain in the ass. Plus I don't want to have paid a couple thousand bucks for a product that kinda works.

IMO, if we can identify a problem, this is a fix for Grace Design or Sound Devices. Thankfully both of these companies have great support and will hopefully address any issues.

[cleantone]

Oh okay. I was more aiming you to saving your recording you had already made. Also info for anyone else who might want to know how to identify the problem track. That other thread didn't fully get that across either.

I agree that it should not happen at all. I would be a really bent myself. You pay out your ass to be able to record 4 channels in the field for a reason right? I am wondering how the hell they can make a 4 channel field recorder that manages to reverse polarity and cost thousands. It seems like this should have been caught by testers or something. Hopefully a firmware upgrade can and will solve this for you.

[wboswell]

When I originally brought it up, here and on the SD forum, no one could explain it.  I'm pretty confident that the kc5's are properly wired and I double checked the interconnects and they were/are properly wired.  That leaves either the V3 or the 744t. 

C. Fox called me one day and told me that he had been on the SD forum and someone was able to figure out the problem, but honestly, I can't remember much of what he said.  I would suggest reviewing that board for some help.

[fsulloway]

PS- I'm in NYC right now and I PROMISE I'll send those Tishamingo DAT's as soon as I get home! 

Sure you will.

You might want to give Charles a call as he had this problem too. I'm pretty sure he figured it out though.

[wboswell]

Charles bumped my thread over there and here was the response:

New postPosted: Tue Dec 13, 2005 1:30 pm    Post subject:     Reply with quote
There are differences in arrival times between analog inputs and digital inputs with ALL devices.

There is latency inherent in every analog-to-digital conversion. Take a look at your digital preamp's specifications and look for it's "group delay" or "latency" specification and its polarity specification. A complete specification will list these, and what the group delay is at different sampling rates (it is SR dependent). You can compensate for it (latency) in the 744T.

Our input delay is adjustable in microsecond increments precisely for this issue. Each input can be pushed back in time, so if the arrival time of your digital signals is after the analog signals through the 744T, then you can push back the analog signals to match the digital signals. Looking at recorded waveforms after recording is the easiest way to find out the group delay differences. Again, these will usually be different for each sampling rate.

When using only analog sources, the two identical two-channel A/D's on the 744T are clocked at the same rate. With a mix of A/D converters (744T and some other) you will get some phase difference that needs to be compensated for if you are to maintain absolute phase. Again, this is inherent to all analog-to-digital converters.

One point of clarity, while phase and polarity have a direct relationship, if a circuit "reverses the phase" it is inverting signal polarity. A specification would be written that inputs are "inverting" or non-inverting". While absolute polarity is not as important (arguable point), having all inputs and outputs in the same relative polarity generally is, especially with multiple sources and in sound reinforcement applications.
_________________
Jon Tatooles
Sound Devices
Report Bugs to Support

I'm sure he knows what he's talking about, but I have my doubts that latency is the issue here.  One source is 180* out of phase with the other with the end result being all the low end cancelling out. 

[Dr.FOB]

I'm going to take a leap here and forecast that it is the digi out of the V3 that is causing the problem.
I first noticed this long before I got my 744 when I was running the MOTU Traveller and the V3 together but couldn't eliminate the cables from the equation.

I too believe that my Neumann actives are wired in phase and am certain that the cables I made Friday are wired correctly.

Friday night I ran 4 channels for Jazz is Dead.
I ran split 170s with my new silver clad cables straight into 1/2.  I ran the USM69i into the V3>digi>3/4.
It was difficult to see the inversion with this particular combination due to the physical separation but I could hear it in the mix.

I'll make some comps later tonight and post the results.

[wboswell]

I'm going to take a leap here and forecast that it is the digi out of the V3 that is causing the problem.
I first noticed this long before I got my 744 when I was running the MOTU Traveller and the V3 together but couldn't eliminate the cables from the equation.

I too believe that my Neumann actives are wired in phase and am certain that the cables I made Friday are wired correctly.

Friday night I ran 4 channels for Jazz is Dead.
I ran split 170s with my new silver clad cables straight into 1/2.  I ran the USM69i into the V3>digi>3/4.
It was difficult to see the inversion with this particular combination due to the physical separation but I could hear it in the mix.

I'll make some comps later tonight and post the results.

hmm no.  There is no way Grace could ever do anything wrong!

Seriously, I'm with you.  Its not a minor difference.  We're talking major lack of bass response.  May be worth an email to Grace by someone who cares.

another thing to do would be to route an identical analog signal to all inputs on the 744, then compare the .wavs in DAW.  Then add the V3 and see what happens.  That should tell you something

[it-goes-to-eleven]

Interesting response from SD..  This isn't a problem I was aware of but I can see how it could happen.

If true, this isn't inversion but time offset between channels. I think of inversion as flipping the wires in a cable or inverting the wave in the DAW. 

If this is what SD describes.. The V3 buffers a certain number of samples before starting to stream them down the AES output, that would create a 'delay' on that channel. That delay is simply different then the delay in the 744.  I don't see that as a v3 problem or 744 problem..

Looks like you need to do some good testing with test tones and careful data gathering.

[pilgrims622]

So far, I havent had any phase issues running 4 channels with the v3 and 744....knock on wood

2 different sources so far 4 times....

run for 2 shows
(Neumann ak40+ak20 > lc3 > km100 > Lunatec V3(digi out)) + (Neumann km143) > Sound Devices 744t @ 24/48
&
run for 2 shows
(Neumann ak40+ak20 > lc3 > km100 > Lunatec V3(analog out)) + (Schoeps cmc621xt > Lunatec V3(digi out)) > Sound Devices 744t @ 24/96

I am recording in mono and using the 1 gig split if that helps...Cant think of what else I changed on the 744, but Charles did walk me thru each step like a baby

[cleantone]

For what it is worth, I can say that I have been running AES/EBU out of my V3 for years into my MOTU rig and have NEVER had the polarity reversed. Countless times.

another thing to do would be to route an identical analog signal to all inputs on the 744, then compare the .wavs in DAW.  Then add the V3 and see what happens.  That should tell you something

This is the best way to verify this right quickly.

[wboswell]

Interesting response from SD..  This isn't a problem I was aware of but I can see how it could happen.

If true, this isn't inversion but time offset between channels. I think of inversion as flipping the wires in a cable or inverting the wave in the DAW. 

If this is what SD describes.. The V3 buffers a certain number of samples before starting to stream them down the AES output, that would create a 'delay' on that channel. That delay is simply different then the delay in the 744.  I don't see that as a v3 problem or 744 problem..

Looks like you need to do some good testing with test tones and careful data gathering.

the latency mentioned above would be similar to that of taking a sbd recording and a mic recording made with two different machines and trying to synch them up in post.  I see these two issues as apples and oranges.

I guess I need to touch base with Charles as he had the same problem as I had and seems to have it fixed.

For what it is worth, I can say that I have been running AES/EBU out of my V3 for years into my MOTU rig and have NEVER had the polarity reversed. Countless times.

unless the MOTU has its polarity reversed also

[cleantone]

If true, this isn't inversion but time offset between channels. I think of inversion as flipping the wires in a cable or inverting the wave in the DAW.

If this is what SD describes.. The V3 buffers a certain number of samples before starting to stream them down the AES output, that would create a 'delay' on that channel. That delay is simply different then the delay in the 744.  I don't see that as a v3 problem or 744 problem..

This is why I was asking my initial questions. It seems obvious enough, so it is not likely the case. If your mixing multiple sources you need to time align everything before you mix it. This would be more of a true phase issue and not polarity. The pictures I saw from the linked thread (http://taperssection.com/index.php?topic=49528.0) definitly look like polarity (attatched)

I assume this is the same problem right? This photo clearly shows reversed polarity and not a time delay causeing phase issues. I think it is pretty safe to assume neither pairs of cables were wired backward, right? That would cause (and solve) this issue.

The definitive test would be to route an identical signal (not 4 different mics) to the inputs with the same setup. A sine wave would be usefull. I assume you could get the same results by sending a stereo signal, left channel 744 analog 1, right channel V3 channel 1 to see if the polarity is getting reversed or if there is a latency delay issue. You woldn't really need to run four channels to test it though it would work.

[Dr.FOB]

For what it is worth, I can say that I have been running AES/EBU out of my V3 for years into my MOTU rig and have NEVER had the polarity reversed. Countless times.

There is another thing to check.  Perhaps the outputs are independantly driven with the AES configured differently than the coax SPDIF.

[Brian Skalinder]

Perhaps the outputs are independantly driven with the AES configured differently than the coax SPDIF.

Depends on which AES output you're using on the V3.  AES1 is driven from the same transmitter as the coax S/PDIF output.  AES2 has its own transmitter.

[cleantone]

Dr.FOB,

So you really think it is the V3 sending reversed polarity out the SP/DIF? I REALLY doubt it. I would be VERY surprised if that was the case. I'm beyond curious with this now. I really wish I had the gear so I could figure it out right now. I have used all the outputs of the V3 all at once an never noticed any polarity issues. I have used the analog outs to monitor, one AES/EBU to my rig, one to a backup rig, and SP/DIF to DAT for two track back up all at once. I have never had a polarity issue that did not result from a cable being wired backward. I have also never used the 744. Since this problem has come about from two or more people on this board I have to assume it is something about the 744 unit.

PLEASE figure this out today... 

Depends on which AES output you're using on the V3.  AES1 is driven from the same transmitter as the coax S/PDIF output.  AES2 has its own transmitter.

Didn't know that. I have used either and sometimes both.

[Dr.FOB]

Depends on which AES output you're using on the V3.  AES1 is driven from the same transmitter as the coax S/PDIF output.  AES2 has its own transmitter.

I can also see that a difference might be noted if an XLR>rca connector was wired incorrectly.
But I have been using the coax output...

[wboswell]

FWIW, I used the s/pdif output and not the AES out.

I didn't notice that the two sources were out of phase until I authored a DVD.  On my computer it sounded pretty normal but when I played it back in my den, it was very obvious.  It may not jump out an grab you unless you're putting it on something capable of reproducing the low end.

[jamiex]

Hi all-

Jamie from Grace Design here.  I just received an email from Jim, which drew our attention to the thread.  Sorry there has been so much confusion regarding this.

The digital outputs (AES1, AES2, S/PDIF and TOSLINK) are 180 degrees out of phase.  As you know absolute polarity does not have an affect on the sound when the relative polarity between the channels is consistent.  It does however become an issue if you are summing multiple sources that have inverted polarities, which is the case here.  With the V3 digital outputs 180 degrees out of phase from the analog inputs on the 744, the low frequency response will be compromised if these signals are summed.

The fact that the V3's digital outputs are 180 degrees out of phase was only recently discovered when both the analog and digital outs were recorded simultaneously to a workstation.  Upon discovery we immediately corrected this issue in new production units.  Beginning with serial number V3497, all of the digital outputs are in phase with the input.  Any unit prior to this serial number will have inverted polarity on the digital outputs.

Again, when recording two channel audio this is not a problem, but for multichannel or matrix recordings that use the digital outputs, this should be corrected.  Obviously we are here for any of you who want/need to have the digital output in phase with the input and will provide this service at no charge under warranty.  To arrange for this service, please contact me at jamie@gracedesign.com.

Once again our apologies for the confusion and any trouble this may have caused.

Best regards from snowy Boulder, CO

- jamie

[cleantone]

I'll be damned.  I cannot believe this was overlooked from production and took this long to figure out. I wonder if it is certainly 100% of the units. I'll be testing mine today.

As you know absolute polarity does not have an affect on the sound when the relative polarity between the channels is consistent.

I'm not sure I agree with this. Your changing compression to rarefaction and visaversa. It might not be the most audible thing but I feel like it is an issue.

Always a good idea to test "bugs" first hand before pointing that finger.

I was making assumptions. I was only trying to help. It is NOT my fault the V3 swaps polarity on digi output. I'm really perplexed right now.

[Dr.FOB]

Thank you Jamie for the quick response.

Wow what customer service we get from these guys.  Two of the best, Grace & SD.
Shows that this forum is made up of users who really wring out the features of the equpment offered!

Jim

[cleantone]

wish I just did this before trying to work through it in my head. I had been mixing and on here when resting my ears. I had my MOTU shit on already. I grabbed my V3, plugged in a dynamic to the left channel. Opened a new DP session. Routed the left analog output to MOTU analog 1, track one. Routed AES/EBU 1 (L) to track 2. Recorded a peaky click from my mouth. Low an behold...

[it-goes-to-eleven]

I was making assumptions. I was only trying to help. It is NOT my fault the V3 swaps polarity on digi output. I'm really perplexed right now.

I know.. It was just really strong language at a point when the information was very limited.


As for polarity not making a difference.. I agree that it is a concern.

Now who is going to fix all of those v3 sources on archive.org and how does the right/wrong phase get described in the source line?   

[cleantone]

It was just really strong language at a point when the information was very limited.

I can assure you it probably read stronger that was intended. I THOUGHT I could count on my gear and would have noticed. My foot is in my mouth.

[Dr.FOB]

As for polarity not making a difference.. I agree that it is a concern.

Now who is going to fix all of those v3 sources on archive.org and how does the right/wrong phase get described in the source line?   

I'm sure not going there.

I have enough material to keep me busy forever.  And to those who thought the sound sucked, it did, it should have blown!  It was out of phase.

[Dr.FOB]

not sure whats going on here, but,... might this be the issue that people have referrenced in the V3 adc sounding thin?

Ding Ding
Give the man a cigar!

[Brian Skalinder]

not sure whats going on here, but,... might this be the issue that people have referrenced in the V3 adc sounding thin?

Theoretically, maybe.  But I've done a few mixes with V3 + another source and found the sources out of phase.  BIG impact when mixing out of phase sources.  So I simply corrected before mixing.  But before doing so, I listened to the V3 source in both its default output phase and inverted 180º and couldn't hear a difference.  But I don't have a top notch playback system¹, so...

¹ Digi source > Bel Canto DAC 1.1 > Audio Experiences Symphonies > McCormack DNA-1 > VR1 or Maggie MMG + subwoofer

[wboswell]

I'll be damned.  I cannot believe this was overlooked from production and took this long to figure out. I wonder if it is certainly 100% of the units. I'll be testing mine today.

This also happened with the AD2k+.  It was discovered well after many of the units had been mfg.

edit:
glad to finally have a firm answer on this!!!

[cfox]

Yes, Jamie answered the situation as he did me when I had the problem, the easiest way to get around this is to go 4 analog in's into the 744 to stay away from the "latency" issue, or get your v3 serviced by grace. 
To fix the problem, Just invert the phase for the 2 channels that went digi into the 744, before combining all 4 files...
Its not always that noticable, but once you know of the problem, and start listening, it will stand out like a sore thumb.
Have you guys tried 2 digi in's into the 744 yet?

[wboswell]

Have you guys tried 2 digi in's into the 744 yet?

as long as its two out of phase V3's, it shouldn't be a problem!

[cfox]

Have you guys tried 2 digi in's into the 744 yet?

as long as its two out of phase V3's, it shouldn't be a problem!

It won't record from 2 different digital signals...

[Dr.FOB]

It won't record from 2 different digital signals...

Unless they are locked in sync?

[scb]

nutter and i tried way back when in sept 04 for mule at roseland.  we tried to input a digital signal from a v3 and mytek stereo192.  both a/ds were locked on the same clock....and it didn't work

this was a preproduction unit though,  so a lot could have changed.  but my experience is the 1 time i tried it didn't work

[cleantone]

It won't record from 2 different digital signals...

I wonder why this is? Seems like if you have a masterclock and the two AES inputs it should be able to do this. Man today has been eye opening.

[baustin]

...... Man today has been eye opening.

Wow! 

Posted this this morning while in NYC, get back to SC and 3 pages later! Glad we were able to get to the bottom of this so quickly.

Alrighty.... onto inverting some V3>digi>744t recordings.

-B

[MattD]

call me deaf, but I've never heard a deficit either.
I've been running V3 analog-out to either DSD or the 722, for over a year now, so, my sound memory is beyond wavering.

Well, you'll never hear a deficit with that configuration, since Jamie said it's only the digital outs that invert polarity. I wonder what that would do for the V3/722 tests Michael Miller and I ran last year. I don't think we checked for this.

[it-goes-to-eleven]

I wonder how long Grace has known about the problem but not mentioned it.

[wboswell]

So far, I havent had any phase issues running 4 channels with the v3 and 744....knock on wood

2 different sources so far 4 times....

run for 2 shows
(Neumann ak40+ak20 > lc3 > km100 > Lunatec V3(digi out)) + (Neumann km143) > Sound Devices 744t @ 24/48
&
run for 2 shows
(Neumann ak40+ak20 > lc3 > km100 > Lunatec V3(analog out)) + (Schoeps cmc621xt > Lunatec V3(digi out)) > Sound Devices 744t @ 24/96

I am recording in mono and using the 1 gig split if that helps...Cant think of what else I changed on the 744, but Charles did walk me thru each step like a baby

So did you invert the polarity on the digi in V3 sources in the post?  Since Charles noticed the issue, I'm sure he had you fix it in the post but it makes me wonder if the inverted polarity make as big a difference with a fig. 8 as it does with other directional patterns?

[Brian Skalinder]

So did you invert the polarity on the digi in V3 sources in the post?  Since Charles noticed the issue, I'm sure he had you fix it in the post but it makes me wonder if the inverted polarity make as big a difference with a fig. 8 as it does with other directional patterns?

Not quite the same scenario, but I ran C414's Blumlein (figure-8) > T+ UA5, mixed it with MK41 > V3 and had to invert the phase because the V3 source out of phase relative to the C414 source was audibly noticeable.  I forget offhand which source I inverted, but I distinctly remember inverting each source independently to see if I could hear a difference.  Once I achieved relative phase across all 4 channels, I could not audibly hear the difference.  If memory serves...

[pilgrims622]

So far, I havent had any phase issues running 4 channels with the v3 and 744....knock on wood

2 different sources so far 4 times....

run for 2 shows
(Neumann ak40+ak20 > lc3 > km100 > Lunatec V3(digi out)) + (Neumann km143) > Sound Devices 744t @ 24/48
&
run for 2 shows
(Neumann ak40+ak20 > lc3 > km100 > Lunatec V3(analog out)) + (Schoeps cmc621xt > Lunatec V3(digi out)) > Sound Devices 744t @ 24/96

I am recording in mono and using the 1 gig split if that helps...Cant think of what else I changed on the 744, but Charles did walk me thru each step like a baby

So did you invert the polarity on the digi in V3 sources in the post?  Since Charles noticed the issue, I'm sure he had you fix it in the post but it makes me wonder if the inverted polarity make as big a difference with a fig. 8 as it does with other directional patterns?

At first no I did not invert polarity, but I have done so now...Charles did have me fix it post...

As for the figure 8, I was wondering the same thing...I have not been able to hear much of a difference at all if any after switching the polarity of the midside sources...The V3 was decoding the midside on the fly, so that is my question too....Does it make a difference that anyone knows of when doing midside compared to say cards(din)...I would think that the polarity would be fine as the V3 is decoding the 2 mono channels to stereo then it was outputing them to mono tracks on the 744...that is confusing and if anyone can shed some light on that it would be great!!!

[Dr.FOB]

There was no indication that the decoding of MS was an issue.  The digital output was merely the inverse polarity of the input.

Phase issues with MS would result in swapping Right & Left.  (I don't decode on the fly, so I record a brief message to myself to insure proper R-L orientation on decoding)  This typically comes from the side capsule being oriented in the wrong direction.

With proper inputs Mid on Left, and Side on Right (badge facing right), the V3 will properly decode Left and Right channels, but still output them as the inverse polarity at the digital outputs.

[wboswell]

So far, I havent had any phase issues running 4 channels with the v3 and 744....knock on wood

2 different sources so far 4 times....

run for 2 shows
(Neumann ak40+ak20 > lc3 > km100 > Lunatec V3(digi out)) + (Neumann km143) > Sound Devices 744t @ 24/48
&
run for 2 shows
(Neumann ak40+ak20 > lc3 > km100 > Lunatec V3(analog out)) + (Schoeps cmc621xt > Lunatec V3(digi out)) > Sound Devices 744t @ 24/96

I am recording in mono and using the 1 gig split if that helps...Cant think of what else I changed on the 744, but Charles did walk me thru each step like a baby

So did you invert the polarity on the digi in V3 sources in the post?  Since Charles noticed the issue, I'm sure he had you fix it in the post but it makes me wonder if the inverted polarity make as big a difference with a fig. 8 as it does with other directional patterns?

At first no I did not invert polarity, but I have done so now...Charles did have me fix it post...

As for the figure 8, I was wondering the same thing...I have not been able to hear much of a difference at all if any after switching the polarity of the midside sources...The V3 was decoding the midside on the fly, so that is my question too....Does it make a difference that anyone knows of when doing midside compared to say cards(din)...I would think that the polarity would be fine as the V3 is decoding the 2 mono channels to stereo then it was outputing them to mono tracks on the 744...that is confusing and if anyone can shed some light on that it would be great!!!

The theoretical argument going on is that you may hear a difference when inverting the phase of the two V3 channels, but for practical purposes, I personally cannot hear a difference.  The difference becomes noticeable only when you add another stereo pair recorded 180* out of phase to the V3.