Meridian Unplugged - Powered by MrTechGuy.co.uk Forums Discussion Meridian - Streaming LAN isolator anyone?

Very basic question if I may to those who have a GISO. Should the ground side be connected to the cable coming from my AirPort Extreme or to the cable going out to my 861?

Yes it does, it uses UDP together with application based error detection and re-transmission.

Regards,
Carl

It doesn't?

Ken

The groundside have to go to the 861 side.

Many thanks Robert.

It remains to be seen if there is something to note further on in this particular use, but in general yes, silver sounds a bit "harder" and then they open up that is what I have experienced before on the HD621 RJ45.

I have a Dualband 5GHz/2.4GHz router and several wireless devices in my listening room, I would not characterize it as a low RFI environment. Pretty normal by 2014 standards.

Only doing theory would have every named cable manufacturer go bust IMHO. Looks, image and theory only go so far. And how do we quantify a theoretical difference without listening at the end result?

Looking around the net is interesting, because many pick up on these things and I don't think it's only placebo. There is a pattern in the streamer client-server setup even though it's only LAN packets, and yes I work with IT every day and I won't be buying any Diamonds to the corporate network anytime soon. But it is a phenomenon, first USB cables, network cables, SATA cables, powercables, PSU's. Do people have too much spare time and cash? I think that is a bit too easy explanation.

But anyways I will continue to give feedback of what I experience, good or bad, silver or copper. ;-)

I stand corrected.
But are you sure that the eithernet protocol is the same as TCP/IP?

Perhaps my confusion came from Ronnie�s statement:
�Secondly, as it�s Packetized Data, with built-in error correction and packet re-transmission��

I always understood that the data stream from the Core was a just a one way stream of data.
But not being an IT engineer I may be over simplifying things.

The core decodes the audio media into a PCM like audio 'stream' sent in chunks to audio endpoints of (iirc) 1400 byte UDP packets. Every (iirc) 10 packets, there is a TCP handshake which checks if all packets are present and correct.

Whilst UDP packets do not undergo a ack/nack process for performance, the less granular TCP habdshake fulfils this need.

Either all 14000 (10x1400 bytes) intact, or all are retransmitted. There is plenty of buffering to allow multiple retransmission attempts without audio disruption.

If the data stream 'breaks', the disruption is highly audible (audio breakup) and far from subtle.

This process happens whether or not the audio endpoint is remote (ie MD600/ID4x) from the Core or integrated (ie MC200). The latter uses internal networking stack and packets do not physically travel across network hardware.

To hear the effects of datastream breakup, use Control:Mac/PC (not Control:Web which uses a different protocol) on a wireless device and walk away from wireless access point/router until wifi signal becomes marginal.

Thanks Ian.

I have a clearer picture now.

Some questions were raised earlier about what is and isn't in the Emo Systems isolation product. This diagram is from the data sheet for the EN 70 isolators.



Soundserge

Sorry Crion
But with your IT background, you should understand that ANY comparison of PCM Transfer via SPDIF......[or indeed AES EBU Balanced Digital over CatX]......compared with the transmission of Packetized Data over Ethernet is akin to comparing Cheese with Chalkdust

The two types of transfer CANNOT be compared for the reasons already explained

You may as well start to compare the PCM Data over Coax to the Serial Comms Data over Din cable that were and still are in use between Meridian components......you simply cannot compare the two mechanisms

You then bring up using a certain AQ "RJ45" cable from your HD621.......you surely must understand this is a proprietary MMHR connection, which again allows PCM Streaming data to be transferred from the HD621 to the 861??.......this has NOTHING to do with Ethernet Data over Catx.......and it is a COMPLETELY different type of data transfer

With Ethernet transfers, it is the PROTOCOL that decides the Integrity of the data transfer, not the cable

And then you raise USB cables??........which is another type of transfer again.......which does not (necessarily) have the built in error correction and retransmission offered by Ethernet

Given your background in IT, you must concede that given all the Transfer Protocols and Methods that are potentially available out there, that there is a reason why Packetized Data with Error Correction and Retransmission has been chosen to basically run the world we live in today. It has been tested in far more Critical situations (many life "threatening" applications) than Audio, and found to be Robust and Integral in multitudes of different conditions.....many of which are far more challenging than any typical home environment

It is the protocol that is used for LAN's; WAN's; Ethernet over Fibre (FTTC, FTTH), Ethernet over Wifi and on and on

And no amount of testing that you may carry out can change the simple fact that the data that ID41 receives is completely Transparent (and therefore any differences INAUDIBLE), no matter what Silver, Gold, Diamond or Fibre has been used for the data transfer

SUMMARY (For Meridian Audio Components)
1) The Type and Construction of the cable used MAY have an impact on PCM over Coax and Speakerlink AES/EBU......due to the Protocols used

2) The Type and Construction of the Cable Core has ZERO impact on Ethernet Packetized data transfer

3) The Shielding and Screening of CatX cable used for Ethernet transfer CAN theoretically allow the propagation of RFI / EMI across the cable and into the Meridian device.......therefore the use of inexpensively available SSTP is suggested

Why do you say that Robert? Just curious because I was told to have the ground side go to my Ethernet over Powerline adaptor rather than my MS600.