Two CD Transports--Different Side of Speakers

[Kent10]

Hi,

 

I am comparing 2 CD transports.  I have one (old Sony 5 CD Changer CDP-CE375) connected via Optical Output to a Gustard R26 DAC and the second (new Jay's Audio CDT3 MK3) connected via I2S HDMI to the R26.  Playing a Miles Davis CD, there is a track that starts in the right speaker for the Sony transport and the left speaker for the Jay's.  In other words, the speakers are reversed for each transport.

 

Probably something obvious, but I can't figure out why they would be different.

 

Thanks, Kent

 

 

Edited September 9, 2023 by Kent10

[POV]

Fascinating.  What’s the track out of interest?  

[aechmea]

Hi @Kent10 You are indeed having "fun" with your Gustard DAC.

 

Bearing in mind that I don't know and that I am writing this from intuition ...

 

S/PDIF is a defined/documented standard for transmission of PCM data.  It has been around for decades and there is no choice involved for the designers of equipment.  It is what it is.  In the control block there is a bit? that indicates which channel is which.  The data for L and R channels is multiplexed (mixed together) in a continuous stream and the DAC uses the control bit to separate the stream into L and R.

 

I2S is meant for internal connections so there is no standard for using it between 2 external boxes.  The output pins of one implementation may not match the way the designer has connected to the input pins at the other end.  I2S also has a multiplexed data stream and a clock connection which signifies L and R.

 

It is very unlikely the Sony has S/PDIF wrong, so I therefore suspect that that the Jays is sending the wrong bit to signify L or R or perhaps the Gustard has it back-to-front.  Something like that; internal to the trace/chip/firmware of either or both.  Maybe the positive and negative pins of the LR clock have been reversed or ????  I doubt very much whether you can do anything about it.

 

Even though I2S is becoming more common between separate boxes there is no guarantee that the sending end and the receiving end are compatible.  I also seem to recall that there is no error correction with I2S so the correct transmission is not guaranteed.  It is simply not designed nor intended for "external" use.  Why designers decided that they would offer it as an external connection type escapes me.

 

Hopefully an electronics person may know exactly what has happened between your spinner and DAC.  I suspect that @POV works in the area.

[georgehifi]

9 hours ago, Kent10 said:

Playing a Miles Davis CD, there is a track that starts in the right speaker for the Sony transport and the left speaker for the Jay's.  In other words, the speakers are reversed for each transport.

 

You may want to read this. 

https://e2e.ti.com/support/audio-group/audio/f/audio-forum/389451/swapping-left-and-right-channel-in-a-i2s-audio-stream

 

Cheers George

Edited September 9, 2023 by georgehifi

[POV]

17 minutes ago, georgehifi said:

 

You may want to read this. 

https://e2e.ti.com/support/audio-group/audio/f/audio-forum/389451/swapping-left-and-right-channel-in-a-i2s-audio-stream

 

Cheers George

That’s relevant but the question posed by the user is not answered.

[Kent10]

30 minutes ago, POV said:

Fascinating.  What’s the track out of interest?  

Miles Davis--Sketches of Spain--Track 1--right at the beginning there is an instrument that is only in one channel.  But I believe the speakers are reversed for all tracks and all CD's not just this one track.  It just became obvious to me because this instrument was only sounding in one speaker.

[Kent10]

34 minutes ago, aechmea said:

Hi @Kent10 You are indeed having "fun" with your Gustard DAC.

 

Bearing in mind that I don't know and that I am writing this from intuition ...

 

 

Thanks for all this info.  I am using I2S because I have read from several including the distributor of Jay's in the US, that the I2S is the best connection for this unit.  Not knowing any better that is what I bought.  I am not sure if the reversing of the speakers will be important for me, but I am curious.  I am expecting a better I2S HDMI cable in 2-3 weeks, so I will see if the same occurs then.

[georgehifi]

11 minutes ago, POV said:

That’s relevant but the question posed by the user is not answered.

 

Yet again twisting things, I didn't claim it to be, but it's a lot more than the OP's getting here and gives the him directions to start looking in. 

Edited September 9, 2023 by georgehifi

[Kent10]

28 minutes ago, georgehifi said:

 

You may want to read this. 

https://e2e.ti.com/support/audio-group/audio/f/audio-forum/389451/swapping-left-and-right-channel-in-a-i2s-audio-stream

 

Cheers George

Thanks George.  Very interesting.

[georgehifi]

3 minutes ago, Kent10 said:

I am expecting a better I2S HDMI cable in 2-3 weeks

 

I'd be very surprised if L & R can get reversed within the digital stream of an I2S cable.

 

Cheers George

 

[muon*]

Try connecting the Jay's to the Gustard with SPDIF.

[POV]

3 minutes ago, georgehifi said:

 

Yet again twisting things, I didn't claim it to be, but it's a lot more than the OP's getting here and gives the him directions to start looking in. 

Take off the tinfoil hat George.  Not twisting anything, just observing that a user is posing a question on that technical forum and it doesn’t get answered.

 

 

[Kent10]

12 minutes ago, muon* said:

Try connecting the Jay's to the Gustard with SPDIF.

I'll see what I have and give that a try some time.  Thanks. 

[Kent10]

18 minutes ago, georgehifi said:

 

I'd be very surprised if L & R can get reversed within the digital stream of an I2S cable.

 

Cheers George

 

Right.  I might have to adjust the switches in the Jay's.  Cable probably won't do anything.

[POV]

24 minutes ago, Kent10 said:

Miles Davis--Sketches of Spain--Track 1--right at the beginning there is an instrument that is only in one channel.  But I believe the speakers are reversed for all tracks and all CD's not just this one track.  It just became obvious to me because this instrument was only sounding in one speaker.

I see, I have a copy that album but it’s the mono version I think?

 

Assume you are talking about the percussion instrument (sorry not sure what it is).  I just quickly tried it via Spotify and it’s coming through both channels but more loudly through the left channel.  Is that what you are getting with your Jays via i2s?

[Kent10]

Just now, POV said:

I see, I have a copy that album but it’s the mono version I think?

 

Assume you are talking about the percussion instrument (sorry not sure what it is).  I just quickly tried it via Spotify and it’s coming through both channels but more loudly through the left channel.  Is that what you are getting with your Jays via i2s?

Yes the percussion instrument.  I, also, am not sure what that is.  Maybe, I'll look it up.  Yes, with the Jay's I am getting the instrument almost completely out of the left channel and with the Sony almost completely out of the right.  You can hear it a little in the other channel but the difference is very obvious and that is why I noticed it.  So maybe the Jay's is correct and the Sony is wrong.  Just tried the CD in my computer and it is also coming out of the left side primarily but as you say I can still hear it from the right while in my stereo it is just barely heard in the other side.

[bob_m_54]

You might want to ask management to combine this thread with your thread on I2S connectors.

 

Data and L R Clock polarity can be reversed using the Dip switches in the Jay's Transport.

Edited September 10, 2023 by bob_m_54

[POV]

Just now, Kent10 said:

Yes the percussion instrument.  I, also, am not sure what that is.  Maybe, I'll look it up.  Yes, with the Jay's I am getting the instrument almost completely out of the left channel and with the Sony almost completely out of the right.  You can hear it a little in the other channel but the difference is very obvious and that is why I noticed it.  So maybe the Jay's is correct and the Sony is wrong.  Just tried the CD in my computer and it is also coming out of the left side primarily but as you say I can still hear it from the right while in my stereo it is just barely heard in the other side.

Yeah that makes sense, since the original recording was a mono, it’s always going to be present in both channels.

 

Have you got and other albums with tracks that have very distinct left or right channel elements or panning left to right or similar that you can use to try?  Maybe something that was recorded in stereo?  Ideally something you are familiar with.

 

 

[Kent10]

14 minutes ago, POV said:

Yeah that makes sense, since the original recording was a mono, it’s always going to be present in both channels.

 

Have you got and other albums with tracks that have very distinct left or right channel elements or panning left to right or similar that you can use to try?  Maybe something that was recorded in stereo?  Ideally something you are familiar with.

 

 

I'll have to think about it or try a few.

[Kent10]

5 hours ago, POV said:

Yeah that makes sense, since the original recording was a mono, it’s always going to be present in both channels.

 

Have you got and other albums with tracks that have very distinct left or right channel elements or panning left to right or similar that you can use to try?  Maybe something that was recorded in stereo?  Ideally something you are familiar with.

 

 

I found another CD where it was obviously on one side to start.  The Sony and Jay's were both different just like the Miles Davis.  And the Jay's was the same as my computer speakers which are correctly set up because I played a video test with left and right.  So it seems the Sony is wrong.  I wonder why.

 

The CD I found was one with kids' songs and was slightly scratched.  It did not do well in the Sony attached to the R26 while the Jay's did perfectly fine from the little I played.  Another oddity.  You'll recall the other thread I started discusses this and it seems it has something to do with the combination of Sony and R26 because the Sony with my old DAC does fine too.

[POV]

@Kent10 Can you check the settings on your Gustard DAC please.  There is a phase invert setting, is it set to disable or enable?

 

I’m wondering if what’s causing your situation is the Jays phase inverted via i2s as per the dip switch discussion in the other thread and then your DAC also phase inverted which may explain why it’s appearing as though your Sony has the left and right channels inverted.  
 

Edit: Actually looking at the menu, possibly the the phase invert is not applied to i2s, so could be it’s impacting the Sony and not the Jays and the Jays is actually correct phase.

Edited September 10, 2023 by POV

[bob_m_54]

From the other post, the I2S pinout diagrams show that the default settings of the DIP switches in the Jay's gives the data and LR Clock signals in reverse polarity, to what the Gustard is expecting.

 

[Addicted to music]

12 hours ago, aechmea said:

Hi @Kent10 You are indeed having "fun" with your Gustard DAC.

 

Bearing in mind that I don't know and that I am writing this from intuition ...

 

S/PDIF is a defined/documented standard for transmission of PCM data.  It has been around for decades and there is no choice involved for the designers of equipment.  It is what it is.  In the control block there is a bit? that indicates which channel is which.  The data for L and R channels is multiplexed (mixed together) in a continuous stream and the DAC uses the control bit to separate the stream into L and R.

 

I2S is meant for internal connections so there is no standard for using it between 2 external boxes.  The output pins of one implementation may not match the way the designer has connected to the input pins at the other end.  I2S also has a multiplexed data stream and a clock connection which signifies L and R.

 

It is very unlikely the Sony has S/PDIF wrong, so I therefore suspect that that the Jays is sending the wrong bit to signify L or R or perhaps the Gustard has it back-to-front.  Something like that; internal to the trace/chip/firmware of either or both.  Maybe the positive and negative pins of the LR clock have been reversed or ????  I doubt very much whether you can do anything about it.

 

Even though I2S is becoming more common between separate boxes there is no guarantee that the sending end and the receiving end are compatible.  I also seem to recall that there is no error correction with I2S so the correct transmission is not guaranteed.  It is simply not designed nor intended for "external" use.  Why designers decided that they would offer it as an external connection type escapes me.

 

Hopefully an electronics person may know exactly what has happened between your spinner and DAC.  I suspect that @POV works in the area.

 

 

35 minutes ago, bob_m_54 said:

From the other post, the I2S pinout diagrams show that the default settings of the DIP switches in the Jay's gives the data and LR Clock signals in reverse polarity, to what the Gustard is expecting.

 

 

[POV]

56 minutes ago, bob_m_54 said:

From the other post, the I2S pinout diagrams show that the default settings of the DIP switches in the Jay's gives the data and LR Clock signals in reverse polarity, to what the Gustard is expecting.

 

But it seems like the Jays is playing in the correct phase, whilst the Sony isn’t.  The manual for the DAC indicates that the phase inversion is not applied to i2s but is applied to coax.  So I’m curious, as this may explain the odd set of symptoms.

[Kent10]

2 hours ago, POV said:

@Kent10 Can you check the settings on your Gustard DAC please.  There is a phase invert setting, is it set to disable or enable?

 

I’m wondering if what’s causing your situation is the Jays phase inverted via i2s as per the dip switch discussion in the other thread and then your DAC also phase inverted which may explain why it’s appearing as though your Sony has the left and right channels inverted.  
 

Edit: Actually looking at the menu, possibly the the phase invert is not applied to i2s, so could be it’s impacting the Sony and not the Jays and the Jays is actually correct phase.

The phase setting on the R26 is set to "non-inverted."  Changing this setting to "inverted" did not change invert the channels on either the Jay's or the Sony.

 

Yes, now I am thinking the Jay's is using the correct channel and the Sony is reversed based on finding a 2nd CD that does the same and also the computer speakers match what the Jay's is doing.