This is something I've had an in interest in testing for a while. It's something that I read somewhere a while ago. Since being at home self isolating with time on my hands I put it to the test.
Here is Scotland we have 4 main suppliers of electricity, Scottish Power (SP), SSE (Scottish & Southern Energy), EDF Energy and Npower. There are loads more smaller companies but for the sake of this test I thought I'd stick with the big 4.
What I elected to do over the course of the last couple of weeks was spend 3-4 days with each supplier and listen closely to my hifi for sonic variations. I'm used to changing supplier depending on the price deals they have at any particular time, so switching frequently to a new company is nothing new to me.
I selected 6 tracks that I know well:
'Yes Is a Pleasant Country' by Suzanne Abbuehl.
'You Never Know What You're In For' by Elliott Murphy.
'Fools Gold' by The Stone Roses.
'Lost Verses' by Sun Kil Moon.
'You're Too Young' by Vast.
'April' by Blank & Jones.
What I noticed over the course of a couple of weeks of listening was that EDF and SSE had, to my ears, very little difference between them sonically. Both these two suppliers gave the music a rich warm tone but at the cost of a veiled clarity and less separation between instruments. The remaining two suppliers were distinctly different in how they influenced the sonics of the songs. For deepest bass albeit with subdued treble, Npower was the preferred supplier. But, when it came to Scottish Power their electricity provided a dynamic transparency with a wide soundstage. The clarity of the instruments and timbre of the vocals really shine through. Good deep controlled bass and refined highs too. Often, it sounded as though the performers were standing right there in the room with me.
So, the clear winner in terms of how it benefits the overall sound is Scottish Power. Unfortunately the monthly cost is a little higher than the other 3. I think it's worth it though and so I've switched to them for the longer term.
I'd be interested if any others here have thought to conduct similar experiments with their electrical supply.
Anyway Spring is here, a new month, a new electricity supplier.