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post #916 of 1644
I will for sure. I hope in all of this I better hear a difference as I do with the AP1 and PP . That makes a difference for sure. But not so much wth the M7 though. But it does noticeable improve other dacs I have ..

Ps if the cable I get is cheap I will be the first one to say it , and then I will make a cat7 shielded with spec grade connectors..
Al D
post #917 of 1644

I took a better look at the Revelation web page and it appears they are using flat CAT 7 of some type.   So I am going get a short piece of CAT 7 and try again at rolling my own.   I am back currently using the homebuilt CAT 5 cable and nixed the SATA cable.  I think it sounds better.

post #918 of 1644
Ok I feel better if it is a cat7 flat that must be custom. I do not think Belden makes one
post #919 of 1644

I've been reading about various CAT cable types.  CAT 7 takes a shielded terminator called GG-45 plug that is compatible with standard RJ-45 jacks.  CAT 6 wires are larger in diameter than CAT 5(e) and require a special plastic RJ-45 plug to accommodate the wire size.  So I have no idea what Revelation uses from their pictures.


Edited by DACLadder - 10/28/13 at 12:43pm
post #920 of 1644
Yes that is true the cat 5 and six is about the same connector with the 6 a little bigger but same size going into socket. The wire is twisted more turns per inch and has aplastic seep rated inside the four pairs. So the wire is an overall larger diameter . The cat 7 looks like a metal version of the cat6 but the socket is the same as the others . However the female jack is also metal and shielded. . This is also why I spent the money on his cable . What I do not know is the cable really cat7 . But if you looked at Manu website then I guess it is a proprietary to this Manu but cat7 variance . All of these cables are very sensitive to how the cables are setup in connectors and the twist must be tight and into the connector. This is why I own the tester I do. It can tell me the cables are indeed installed correctly for the proper protocol . It is basically frequency sensitive . Anyway thanks for looking into this.
post #921 of 1644

Thanks for putting up with my cable drama with the Off Ramp 5.   ALRAINBOW sent me some pictures of his Revelation I2S cable and it is labeled as CAT 7.   So I have some of that cable spec (Viablue ep7s - not purple Revelation) on order along with shielded CAT 6 plugs.  Believe I will be set when the material arrives.

 

I am glad I first ran the cable experiments with CAT 5e.   I am finding BEST sound with the SHORTEST possible I2S cable.  Now have a 3 inch CAT 5e cable and the sound is glorious and besting the AP1 + PP or USB32.  I also tried 6 and 18 inches with ever degrading results as the cables got longer.  This makes sense physics wise.  So when the CAT 7a cable stock arrives my first cable built will be 3 inches long.   Thanks everyone....


Edited by DACLadder - 11/9/13 at 9:24am
post #922 of 1644
It does make sence . When I bought the ps audio Pwd maki Ii I also bought the PWT TRANSPORT

it has an HDMI i2s output as does the PWD In an email to Paul he recommended that although he sells the cable in to Letha's 1 m and 2 m he said the shorter the better. This is with his cable custom and all I got a deal from him on the cable but they are around 500 .. Crazy but it does make a difference .. Just some thoughts. And I am not a cable be leaver lmao.

Al D
post #923 of 1644
So how does the I2S connection compare to the coaxial S/PDIF - both from the Off Ramp to M7?
post #924 of 1644
I know I spent a lot of money and it is all here in the box but I have not had the time to set it up for a real a/b test. I plan on doing I the morning early. And I will have both units on for a couple if hours to warm them up.
post #925 of 1644
Quote:

So how does the I2S connection compare to the coaxial S/PDIF - both from the Off Ramp to M7?

I have both connected.  With S/PDIF input #3 you can really tell a difference compared to I2S.   Input #3 is warmer sounding with a narrower stage, fuzzier imaging, and less bass.  S/PDIF input #1 sounds closer to the I2S input tonally but there seems to be more detail/ clarity with I2S.  One man's clarity is another's clinical sound but time is improving the 2-week old OR5.  I2S wins the vocal rendition award - more natural with nice breath across the lips. Unnatural sibilance is virtually absent with I2S.

 

To be fair I don't have the OR5 S/PDIF Hynes power option but do have the Hynes for the I2S circuits.

post #926 of 1644

I wish Kingwa had switched to surface-mount connectors for everything and had cases to match. Then a bunch of cabling and headers would have been eliminated in the process. Now if only I could buy the plugs for the headers inside the M7, I could easily rig my own I2S cable.

post #927 of 1644
Quote:
Originally Posted by DACLadder View Post
 

Thanks for putting up with my cable drama with the Off Ramp 5.   ALRAINBOW sent me some pictures of his Revelation I2S cable and it is labeled as CAT 7a.   So I have some of that cable spec (Viablue ep7s - not purple Revelation) on order along with shielded CAT 6 plugs.  Believe I will be set when the material arrives.

 

I am glad I first ran the cable experiments with CAT 5e.   I am finding BEST sound with the SHORTEST possible I2S cable.  Now have a 3 inch CAT 5e cable and the sound is glorious and besting the AP1 + PP or USB32.  I also tried 6 and 18 inches with ever degrading results as the cables got longer.  This makes sense physics wise.  So when the CAT 7a cable stock arrives my first cable built will be 3 inches long.   Thanks everyone....

 

Nice find, thanks for sharing.

post #928 of 1644
Quote:

Now if only I could buy the plugs for the headers inside the M7, I could easily rig my own I2S cable.

I've had the same  thoughts... just remove the M7 RJ-45 board from the back plate and bring in the external I2S cable directly to the M7 DSP board header.  Looking at the Audio GD web page of the M7 gut shot I see surface mount resistors on the back of the RJ-45 connector circuit board.  So removing the M7 RJ-45 may also mean removing the cable termination.  But if it is just resistors-to-ground termination then you probably can build that into the cable end point header.   Perhaps Kingwa can tell us the header plug vendor. I'm sure it is something standard but the pitch between pins is hard to judge by the photos.   The internal M7 header cable has five pins so assume the signals are 4 x I2S and 1 GND.

post #929 of 1644
This may be a dumb question on my behalf . But why do this work? What is there to gain I am missing something in this thought process...

Al D
post #930 of 1644

The reason would be a continuous, uninterrupted cable from the IS2 source to the destination.  You would be eliminating one cable RJ-45 plug, M7 RJ-45 jack, RJ-45 circuit board, one header connection, and the internal ribbon cable.  In transmission line theory a change in impedance causes reflections of the signal as it traverses the cable and degrades the signal by the time it reaches the designation.  It is funny if you think about it but we are trying to preserve the digital I2S signals in the analog domain.  S/PDIF coax is a very good example of a well designed transmission line system from source, cable, and destination.

 

I received information today from Steve N. at Empirical Audio (Off Ramp 5 maker).  His OR5 cable experiments concluded best I2S performance (sweet spots) at 6 inches and again at 1.5 - 2 meters of cable length.  Steve concludes.... "for the short sweet-spot, lesser (quality) cable will do".
 

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