Sound quality differences between NAS units

[DavidL]

(02-09-2016 12:37)Martin H Wrote:  .....................

One thing that bothers me a little and I think it is briefly covered in that article is that the converters need power and by definition risk introducing a new problem as I try to fix another. TBH the article was interesting but I was a bit confused with the timeline and what looked like an incomplete shopping list?

It sounds as if you have been impressed by how this has helped you though?

You are correct about being bothered by power supplies for the ethernet wire-to-fibre converters. As sold the converters come with switch-mode power supplies and, at least, the one for the downstream converter (i.e. that nearest the renderer/DAC) should be replaced by a linear power supply. I replaced both. These are readily available but rather than quote some examples it's probably best for you to search locally.

The shopping list is complete (2 converters & a pair of 1 meter [say] fibre cables). As noted later in the blog you can simplify the setup if you only have 1 device you wish to isolate (your main DS), by putting the back-to-back pair of ethernet wire-to-fibre converters in the last leg of the ethernet connection to your renderer/DAC i.e. after your router and any switches in your network.
This Audiostream blog gives a useful pictorial view of the setup for optical isolation:
http://www.audiostream.com/content/barn-...OFbdYIS.97
6 & 8 are TP-LINK converters connected by a pair of fibre cables 7. Upstream of 6 the ethernet connects to modem/router, switch etc. Downstream of 8 the ethernet connects to your player (renderer/DAC).

Incidentally I picked up on Andrew Everard's blog after reading a comment he made in his review of a couple of Melco server / players in HiFi News "very good sound quality but this could be equalled or exceeded (with far less expense) by a NAS with an optimised network" or words to that effect
I did some brief (not really scientific) listening comparisons with and without the optical isolation in place, feeding my PS Audio Direct Stream DAC which has an internal renderer (Bridge II). I felt there was an improvement in SQ but it was not large, presumably because I also have a wireless bridge in my network between the NAS, router, switch, computers etc and the hifi gear.