You are welcome. The IFI SPDIF iPurifier re-clocks and regenerates the signal before being processed by your dac, so I would think the benefits from a W4S upgrade would be marginal and probably not be satisfying in the long term as a primary music source. Looking back on my experience, the W4S Sonos is a very good source for the money but I wanted better sound than it could deliver. Better signal cables and better dacs helped but it always sounded like a digital source, which of course it is. That changed with the mR, which sounds similar to analog sound in my system... when using the Uptone Audio LPS. BTW, I sold the Sonos here on AG last week; it was snapped up in one hour!
I also have an interest in R2R dacs, including some you mentioned and Metrum products. I previously mentioned trying a number of expensive dacs and not finding a meaningful, longterm improvement until replacing the Sonos with a better quality music streamer like the mR. So my caution would be don’t expect a dac to "fix" problems that are better corrected up stream, so to speak.
Another lesson recently learned, and much to my surprise, was that good quality power strips can make a difference when used with routers, modems, switches and servers. I have an Audience AR6 PDC for my stereo setup, and it helps a lot. I recently bought a used IsoTek EVO3 Sirius for the computer gear and WOW, the improvement is amazing. All the digital grunge that accompanied the music signal is gone! Furman Audio makes some less expensive devices you could trial on home demo for around $180. The AudioStream author uses these on his system.
I also have an interest in R2R dacs, including some you mentioned and Metrum products. I previously mentioned trying a number of expensive dacs and not finding a meaningful, longterm improvement until replacing the Sonos with a better quality music streamer like the mR. So my caution would be don’t expect a dac to "fix" problems that are better corrected up stream, so to speak.
Another lesson recently learned, and much to my surprise, was that good quality power strips can make a difference when used with routers, modems, switches and servers. I have an Audience AR6 PDC for my stereo setup, and it helps a lot. I recently bought a used IsoTek EVO3 Sirius for the computer gear and WOW, the improvement is amazing. All the digital grunge that accompanied the music signal is gone! Furman Audio makes some less expensive devices you could trial on home demo for around $180. The AudioStream author uses these on his system.