Can SMPS based preamps/amps sound organic ?

Hi Bombaywalla, hope you are doing well :-)

I started this discussion not because I was imagining things, at least thats what I would like to believe. I had some experiences around SMPS based equipments within my own system. I had a couple of CDP from Linn (Ikemi) and Bluenote, I also had a phonostage which had the option of using an external PSU (where I could try both their SMPS model and Linear PSU model). I also had an opportunity to listen to a very well reviewed amplifier with SMPS. In fact all these equipments are very well reviewed without any mention of any issues around SMPS distortion/noise.

My personal observation though has been different. Since I have heard them all in my own system and that too besides some other non-SMPS based equipments I do not doubt what I felt about them. All of them had the ability to sound faster and more transparent. Air and Resolution also goes up compared to similarly priced equipments with Linear PSU. All this is great hence there is a certain wow factor there. Where things start to fall apart is in some inherent noise/hash/distortion whatever you call it which is not audible as a straight forward graininess or muddiness that we are typically accustomed with linear PSU. It is rather something that affects the tones and presentation which ultimately results in a less relaxed sound. Mind doesnt relax to the music but is always constantly being stirred with whats going on. There is a bit of frown, a bit intrigue, a bit of wow, all mixed up because that distortion or noise however little is neither ignorable nor passable as music, something very similar to distortion/noise of a CD vs LP.

Recently I had an amplifier at home which sounded terrific in many respects, one of the fastest, most well resolved most dynamic amps I have tried. Yes it had a very "advanced" SMPS and thats also its USP. While I was trying to get a hang of its sound I was constantly getting bothered about something that was not "usual". Especially the high frequency on the amp sounded like an early digital CD player, but then my source is a Garrard 301 played back through a Klyne phono + preamp. It is a great analog combo though a bit vintage to some ears. With this amp it sounded like digital media player which has not been fully done up especially in the highs and also in the lows, the bass suddenly reminded me of typical digital bass, which is quite unlike the bottomless analog bass we expect from a good analog source. As I was trying to decipher all this, I played an LP which had some clicks and pops, to my surprise the clicks and pops which I generally find ignorable in some of these LPs now grabbed my attention more than ever. The clicks and pops were sounding like there is some shiny disc being played in my system. They sounded hot, sparkly and sharp like flashes of fire dots. I tried various power cords and ICs especially shielded ones to see if some RFI/EMI is causing it but things remained pretty much the same. That quite nailed things for me and hence I started this thread.

Long time back I read an article which said, when one is listening to an amplifier, he is actually listening to its power supply. It is ubiquitous that all PSU do distort to some extent or other based on various factors. These distortions are definitely different in a Linear PSU vs an SMPS, typical analog vs digital. What it does to the sound is also going to be different. It is just that I find one of them to be much more forgiving and listenable than the other.

Designers probably take their stands based on various factors. They need to wow their customers and investors and get things going to the market quicker than their competiros. The fact that reviewers and most stake holders in the industry accept it without a"frown" probably makes it easy for them. Having said all that I havent heard the Rowlands and Soulution yet.

I'm doing well. thanks for asking. I see that you are also doing well & growing by leaps & bounds as an audiophile. :-)
thanks for your feedback, Pani. Now your original comments make a lot more sense. Would have been nice if you had stated all this in your 1st post to give all of us a background where you were coming from. ;-)
anyway, it looks like we have a variety of opinions on this topic from several owners & listeners..... 

@pani
As stated above SMPS has come a long way. But I can think of a reason a LPS may sound better in your home. One thing is a transformer will filter out or reduce incoming high frequency electrical noise where especially older SMPS will pass it through.

That said I'm the type of listener who stopped relying on specs and measurements when deciding what to buy. At least for me it left biased one way or the other.

Given the positive and encouraging comments here with regard to SMPS  what explains the continued popularity  of linear power supplies?  It leads me to suspect that they must have some significant inherent justification. Or is it just stubbornness on behalf of many builders?

I'd love to 'switch' (if you will pardon the expression) to SMPSs but to get the voltages we need for our products simply isn't in the cards unless we buy a lot of supplies, costing 10s of thousands of dollars. For a small business its not practical unless the power supply is conveniently available off-the-shelf. So traditional supplies will be with us a long time.

But I can think of a reason a LPS may sound better in your home. One thing is a transformer will filter out or reduce incoming high frequency electrical noise where especially older SMPS will pass it through.

Modern SMPS often contain Power Factor correction module, basically a huge inductor and capacitor, making supply appear as resistive load but also filtering any line noise. They are also line and load regulated with fast response that will eliminate in tandem with supply capacitors most of the line noise. In contrast, most of linear power supplies draw supply current in short spikes of high amplitude that "travel" thru the power cord and pollute everything around. The only thing "linear" about "linear power supplies" is that they are unregulated. I would suggest replacing word "linear" with "unregulated" since they (most of them) operate as primitive unregulated switchers - nothing linear about it.