BowsAndArrows
Major Contributor
ok boys, I know everybody's been waiting for this update... strap in this is gonna be a LONG one! 
(Disclaimer: please don't let anything I say here ruffle your feathers!! Even if you disagree - relax it's just a WiiM forum!
)
i've made the following changes to my system:
A - WLAN repeater in bridge/client mode to isolate ethernet noise (with some ferrite cores but no torroidal choke yet)
B - powering both the WLAN repeater and streamer (WiiM Pro) with the topping p50 LPS
C - ifi S/PDIF ipurifier2 connected via ifi's included toslink>mini-toslink to the streamer, and then my new glass optical cable l via ifi's mini-toslink>toslink (needed a new longer cable anyways) to my active speakers
the biggest change i noticed was turning all the radios off and switching to the isolated lan from A. B didn't seem to have much of an additive effect after that... however, adding C to the equation improved SQ similarly to when i added A but to a lesser extent. especially listening to songs with a lot of "competing" treble noises - it seemed easier to pick them out individually...
like in the song "Talk to the Lord" by Natalie Bergman
- there is this faint crackling noise (like you are listening to her on the FM radio) - before i added C to my system - it was hard to notice the periodic nature of this faint crackle - there’s an audible pop in the crackling that is slightly off beat to the song’s rhythm… 
it's as if the added transparency allowed me to decipher that this is indeed a loop added to the production digitally, and not an actual crackle that would be present if they used analog equipment like a tape deck to record it which would have random crackles and pops. you know kinda like that "old-timey" cinema effect poeple use on youtube videos that don't look real? kind of like that... similarly when the rest of the choir join in on the song then you can almost count the number of people that are singing at any given time, and almost recognise each of their voices when they sing different parts of the song.
in john coltrane's "they say it's wonderful", here you can kind of clearly hear the brushes being played on the cymbals coming out of the left channel.
The off-axis performance (esp horizontal) has improved significantly.
This was already a strength (both horizontal and vertical off-axis performance) of my speakers but it's ridiculous now!!
Then I listened to some norah jones tracks that i know well, and to me the cohesiveness of the sound top to bottom has improved. in particular, the high frequency range has noticably become less fatiguing (which was a bit of an issue i had with my system - small room and acoustic treatment that is ok but can be improved) and it seems easier to pinpoint sounds in the stereo field.
the low end sounded a bit subdued compared to before but it seems to have better timing/control and less smudging of the sounds in that frequency range.
i did a fair amount of A/B testing, and for now i think i'm just gonna let the system settle down and see if i notice anything new.
i do suspect that if i took away A and instead just keep C, then the difference compared to neither would be similar to when i added A alone. but that’s for another day...
my reasoning for why the LPS didn't make much of a difference is maybe because it hasn't got a way to affect the voltage in my active speakers connected via another SMPS brick (and therefore can’t influence the reference voltage for the DAC)... who knows? i still think i'm gonna end up keeping it cos it looks really cool, it's small and it works silently + it's convenient for powering both the streamer and the WLAN repeater with one outlet.
one interesting side benefit i did actually notice which is weird but replicable is that once i switched to this new optical cable, i never get these like crackle and pops + almost like a CD skipping effect whenever i wake my system up from sleep. this usually happened EVERY time at the start of songs - for the first 4-5 seconds when it wakes up before i switched to the glass optical cable. and it's not happened since...
(Disclaimer: please don't let anything I say here ruffle your feathers!! Even if you disagree - relax it's just a WiiM forum!
)i've made the following changes to my system:
A - WLAN repeater in bridge/client mode to isolate ethernet noise (with some ferrite cores but no torroidal choke yet)
B - powering both the WLAN repeater and streamer (WiiM Pro) with the topping p50 LPS
C - ifi S/PDIF ipurifier2 connected via ifi's included toslink>mini-toslink to the streamer, and then my new glass optical cable l via ifi's mini-toslink>toslink (needed a new longer cable anyways) to my active speakers
the biggest change i noticed was turning all the radios off and switching to the isolated lan from A. B didn't seem to have much of an additive effect after that... however, adding C to the equation improved SQ similarly to when i added A but to a lesser extent. especially listening to songs with a lot of "competing" treble noises - it seemed easier to pick them out individually...
like in the song "Talk to the Lord" by Natalie Bergman
- there is this faint crackling noise (like you are listening to her on the FM radio) - before i added C to my system - it was hard to notice the periodic nature of this faint crackle - there’s an audible pop in the crackling that is slightly off beat to the song’s rhythm… it's as if the added transparency allowed me to decipher that this is indeed a loop added to the production digitally, and not an actual crackle that would be present if they used analog equipment like a tape deck to record it which would have random crackles and pops. you know kinda like that "old-timey" cinema effect poeple use on youtube videos that don't look real? kind of like that... similarly when the rest of the choir join in on the song then you can almost count the number of people that are singing at any given time, and almost recognise each of their voices when they sing different parts of the song.in john coltrane's "they say it's wonderful", here you can kind of clearly hear the brushes being played on the cymbals coming out of the left channel.
The off-axis performance (esp horizontal) has improved significantly.
This was already a strength (both horizontal and vertical off-axis performance) of my speakers but it's ridiculous now!!
Then I listened to some norah jones tracks that i know well, and to me the cohesiveness of the sound top to bottom has improved. in particular, the high frequency range has noticably become less fatiguing (which was a bit of an issue i had with my system - small room and acoustic treatment that is ok but can be improved) and it seems easier to pinpoint sounds in the stereo field.
the low end sounded a bit subdued compared to before but it seems to have better timing/control and less smudging of the sounds in that frequency range.i did a fair amount of A/B testing, and for now i think i'm just gonna let the system settle down and see if i notice anything new.
i do suspect that if i took away A and instead just keep C, then the difference compared to neither would be similar to when i added A alone.
but that’s for another day...my reasoning for why the LPS didn't make much of a difference is maybe because it hasn't got a way to affect the voltage in my active speakers connected via another SMPS brick (and therefore can’t influence the reference voltage for the DAC)... who knows? i still think i'm gonna end up keeping it cos it looks really cool, it's small and it works silently + it's convenient for powering both the streamer and the WLAN repeater with one outlet.
one interesting side benefit i did actually notice which is weird but replicable is that once i switched to this new optical cable, i never get these like crackle and pops + almost like a CD skipping effect whenever i wake my system up from sleep. this usually happened EVERY time at the start of songs - for the first 4-5 seconds when it wakes up before i switched to the glass optical cable. and it's not happened since...
