SPDIF vs. AES/EBU Sound Quality?

I’ve got an entry level digital coax cable made by Silnote Audio going from my Bluesound Node 2 to my MHDT Orchid DAC out to my BAT VK-5i tube preamp via RCA to balanced XLR. My Audiolab 6000CDT cd transport only support digital coax and TOSLINK. Silnote Audio doesn’t think TOSLINK is up to par. So they don’t make a cable in that type. I bought a Wireworld Supernova (their best quality cable by a wide margin) and I have to say the TOSLINK sounds really good. I made sure to use a very short cable. As long as the DAC designer made all of the ports support the same level of sounds quality there shouldn’t be a difference when applied optimally. Once I’ve settled in with the TOSLINK I’ll compare CDs switched over to digital coax. I’m betting they will be comparable.

Uhm, a "commercial grade BNC" cable does not necessarily mean it is good.

I think my statement may have been confusing.  If your transport and/or DAC use RCA sockets for SPDIF, you are best off using a digital cable with real BNC connections on each end - then attach a BNC-to-RCA adapter.  In my testing I have seen better results with this configuration instead of just using a digital cable with only RCA plugs.

There are many vendors that sell SPDIF cables with BNC terminations.  Examples are Nordost, DH Labs, Black Cat, Acoustic Zen, etc.

Even with BNC terminations on the cable, there are still going to be differences in sound between cable models (i.e. they will all sound different anyways - some will sound better than others in your system depending on system synergy).

A "commercial grade BNC cable" is likely just a standard low cost RG6 cable with BNC terminations - probably something similar to a Beldon cable (nothing special).  The $200 DH Labs D-750 cable will still be better than the commercial grade cable.

@auxinput,

Question, What would be better, a good digital rca with  BNC adapters or a commercial grade BNC cable?

Thanks and Happy New Year!

JD

I just switched from a digital rca cable to an AES/EBU digital cable and it’s slightly louder, but I’ll give it some more time and a/b before I’ll give you the complete answer.

JD

I will mirror opinions above.  Any S/PDIF interface that does not use a true BNC connection is compromised.  If you are unfortunate to have RCA connections for your SPDIF, the best results you will get is if you use BNC cables with BNC-to-RCA adapters.  If you just use RCA cables, even the best SPDIF cables will have compromised high frequencies.

For what it’s worth, I recently bought a Simaudio Moon transport to pair with my Moon DAC. I called Simaudio and asked if I should upgrade to AES/EBU or keep using my current SPDIF cable. Their reply was “spend the money on music.”

I2s/IIs

I agree with mahler123's above comment .

In my particular case , I have a Mojo EVO DAC connected to a SimAudio 260DT transport , I found that shifting to the AES connection on both brought an uptick in SQ from SPDIF. I don’t stream so I have no experience with the USB connection vis a vis the AES or SPDIF

SPDIF unless terminated in proper 75 ohm BNCs, is my least favored way to move a digital signal. AES works well, and I have also been quite satisfied with USB 2.0 

Here is some information on the topic.

I have liked the sound of AES/EBU over SPDIF when inputting to previous DACs I have owned but different DACs use different input boards, some better than others.  My current Mojo Audio DAC is optimized for best performance from the USB inputs and my former Metrum DACs were optimized for I2S, so I used the optimized connections with each of those DACs. 

One reason AES/EBU may sound better with some DACs is discussed as point #2 (below) in the linked article.  I wonder if this may make the quality of the AES/EBU cable less critical than with SPDIF cables?

2) AES/EBU uses uses ten times the signal level of SPDIF, meaning it can tolerate more loss in long cables and if a receiver circuit has been optimised for AES/EBU it will work better as SPDIF will be at the lower limits (too much noise)

+1 those are inherently different cables.  How that effects sound will depend on what you are connecting the Lumin to.  If for example their S/PDIF isn't well implemented, relative to AES/EBU, then there will be a difference.  Not being a Lumin owner, I can't comment

The cables are never the same but there shouldn't be any difference. That doesn't mean there won't be 

Yes, IMHO AES/EBU will provide the best quality up to 24/192 kHz and single rate DSD, for higher sampling rates you'll need USB or I2s.

I've never compared it to I2s but it's been better than USB in every comparison I've done.