How important is a Linear Power Supply Versus a Switcyed one?

I've not heard it but linear supplies generally don't have some of the noise associated with SMPS. If Sutherland deem it an improvement, it most likely will sound a fair bit better. 

It really depends.  Good switch mode power supplies can have phenomenally low noise and high current.... but !! the concern now is  how much noise they inject into the AC. 

This is why I suggest a dual-zone power configuration.

https://inatinear.blogspot.com/2019/04/power-management-for-frugal-audiophiles.html

Both are switching producing high frequency noise, but SMPS done poorly can be really bad, much worse than linear PS. On the other hand SMPS can be much quieter than linear PS if designed for low noise (zero current, zero voltage switching). Jeff Rowland uses SMPS even in preamps, where power losses are insignificant (where he used batteries before). Benchmark reduced noise by 10dB in DAC2 by using SMPS instead of linear PS, they used in DAC1. They also claim that such low level of noise wouldn’t be even obtainable with linear PS. If Sutherland offers this option, then linear PS is probably better, but I would look for reviews, or check return policy. It is always possible that they offer this option only because people demand it (SMPS has bad rap from crude, very noisy computer PS).

I think this is a mod, not an external box, so return would be messy if not impossible. The question is whether it would be noticeably better. 
Forgot to mention that I have a Furman Elite 15 conditioner which got rid of a very slight buzz I had with the volume turned up with nothing playing. Does this make a difference in this discussion/decision?

you know the answer... depends on what unit

some will see a drastic improvement, some slim to none, depends on how much internal filtering/noise isolation is happening inside the unit

but usually it matters and improves at least a teeny bit

That's what I am afraid of....  a teeny bit. I don't consider myself a tweaker and generally don't do things like aftermarket tonearm counterweights, cable stands so they don't touch the floor or that type of stuff. I do care very much about quality and was very pleasantly surprised by a tonearm I bought last year that blew me away (the phono stage made almost the same difference) but a 2 step turntable trade in/upgrade that cost more than the arm made only a very subtle difference and I was disappointed with that, but liked a couple new features so I kept it.  

I am very much aware of the law of diminishing returns and I think I am at the point where my strategy of paying up to $1000 for something noticeable being a no brainer is now impossible. Maybe I am wrong here. I think I am going to call Ron Sutherland - he is a very nice down to earth guy.

I have always found a linear power to be an improvement over a switching power supply.  This is both in analog sources/preamp as well as digital transport sources.  If your system is very warm and laid back, you may not notice any difference.  I think your Plinius integrated is going to be a much higher resolution and revealing amp.  Upgrading your phono stage to linear power supply will likely remove some glare from the sound and give you a smoother and more realistic sound.  I took a look at the Sutherland Insight phono stage.  The power supply is a separate board that can easily be taken out and replaced.  If you google for picture of "Sutherland Loco", you can see what the linear power supply board looks like.  They would use the same one in your Sutherland Insight phono stage.

I have always found a linear power to be an improvement over a switching power supply. This is both in analog sources/preamp as well as digital transport sources.

To give an idea here, there are some hi end manufacturers that offer a power supply upgrade they say is a considerable sound improvement, and that is to pay the extra $$ to get their "linear supply option" installed instead of the smp that come standard with the equipment.

I have yet to bench test any equipment that uses a SMP power supply that doesn’t show HF noise + artifacts infiltrating into the circuit and from the output. Not as low noise as I’ve seen from a good linear supplies.

You’ll get the idea of the HF noise with artifacts if you go near a smp power supply with a portable am radio tuned around 600-700khz off station but (not muted) it’ll squeal it’s head off, and that the airborn radiated stuff, then there’s the stuff that’s going back into the house wiring.

Cheers George

Thanks for all the input.

I spoke with Ron Sutherland and he is the nicest guy. Can't believe he acts as his own distributor and handles inquiries directly.

He said others in the past who did the Insight upgrade were pleased, but he didn't say they were happy they did it and would do it again. He is not a salesman at all and said with or without it, I would be happy, but he knows it it technically better and like some of the posters have said there is some internal noise reduction. The question is, does it sound better to someone with very good, but not Absolute Sound ears.
 
It's an internal board which he said I could do myself, but you have to "jigger a couple things" and blindly thread an LED and it would take an hour (same price if he installs it or not, which was surprising). The second time I would do it would be easier/quicker.... I'm not really looking for a science project. Even though it's only spacers and screws and an LED (no soldering), he said you need to be dexterous.

By the time shipping back and forth is added, it's about $400, almost half of what I paid for the whole phono stage (used). It is a marketing strategy - he charges 25% of list for the linear Power Supply, which seems a bit much compared to the cost difference when manufacturing the LPS board versus the SMP one. I doubt the incremental cost to him is 25% more with the swap. On his 20/20 PS, which is also widely regarded as a great value, he charges $450 for an LPS and it comes in a separate box, so it is easy to compare.Thats a $2200 Phono Stage vs. $1400 for the Insight.

Doesn't matter though - if it is a noticeable improvement, I would do it.

I just don't know....if it was an external box it would be so much easier to compare and return if I wasn't happy.

Does anyone know anybody who has done the upgrade and saw a noticeable difference? I'm of the school that the most important part of the system is the source, so I don't mind spending $$ there.

The amplifiers I use to drive subwoofers are AB and have switching supplies. No transformers. They certainly have no trouble providing a lot of current on demand. For a Phono amp I don't see why not as long as it was well filtered. I'm not sure way the sound would change. If both supplies were well designed it shouldn't. The advantage of the switching supply is efficiency. Maybe it would be a good idea if you run your house on solar panels. 

They say that SMPs introduce noise into the circuit that could impact the sound quality. Sutherland says it's better to have an LPS, but he wasn't acting like it was a really big deal, claims he doesn't like to make minor changes to his personal system but would tell a family member to do it if asked.

I agree with some of the other posts that it would depend on the system as to whether or not I would hear it, and unfortunately, a trial wouldn't be feasible. 

If it was only one or two hundred bucks, I would just do it because it can't hurt (like when I bought better power cables and didn't hear a difference) and I wouldn't be upset about it, but $400 is something more considerable. I guess it all depends on your mentality on spending.

Oh well, I'll think about it....there are certainly bigger issues in the world....maybe if I can get someone reliable to do the install and drop it to $350 and not have to ship the whole unit....

Any power supply introduces noise.  Linear PS is also switching (at max voltage).  The question is how much noise?  They had to have a reason to implement SMPS.  Switchers are usually used for their efficiency when high currents are required or for size when Linear PS takes too much space (wall-warts).  It is neither case so I thought there was a third reason - they can be designed to be extremely quiet, much quieter than Linear PS.  Otherwise why do it?  It is more expensive and more complicated than Linear PS, that has just few very cheap components.   There must be a reason.  Phono stage has RIAA correction that amplifies low frequencies.  It is +20dB@20Hz and likely +12dB@120Hz.  It is likely that it is also sensitive to low frequency power supply noise (120Hz) - common for Linear PS.

Kijank-if SMPS is more expensive, then why is it standard and LPS an extra cost option?

I don't know.  Perhaps SMPS is in standard production while LPS is not (requires modifications).

Not very if both are done well.

Mapman - what are you saying as to why the LPS is an optional extra cost item?

Sorry didn’t read your entire post.
In your case sounds like the maker is saying the linear supply is better for this specific unit. Lower noise level I would expect. Low level Phono preamps do not require a lot of power but are most sensitive to noise. I would expect there would be specs that indicate noise levels in both cases for an upgrade of significant cost. Independent bench tests would be even better. A money back guarantee on the upgrade would also be nice. Or you can just trust them if they are a reputable vendor. Lower noise levels do typically result in better sound. More detail, better soundstage and better imaging.  

At almost any power level, a switch mode power supply will be cheaper than a linear power supply, not to mention more efficient and hence cooler. if standby power is important, they can also superior for that  (think always on waiting for a remote). Of course, they are also smaller if not much much smaller for the same amount of power.

Noise comes down to architecture and of course making the design trade-offs for low noise, which usually means giving up efficiency and increasing cost. A switch mode supply may create more high frequency noise on the AC line, but it can also create far fewer high current harmonics on the AC line at audio frequencies and have much better power factor and much lower THD on the AC input.

I took the plunge and am dealing directly with Ron Sutherland who assured me I will have no problem swapping the boards (which will save the back and forth shipping costs of $50 or so).

No soldering, and he is even willing to get on the phone in case I need any help. Nicest guy. I'll let the discussion know how easy it was and how much better it sounds.

 which seems a bit much compared to the cost difference when manufacturing the LPS board versus the SMP one.

Just the component $cost (not including enclosure) can be more than double for linear v smp.

Cheers George

I wonder what that represents in actual dollars. Double sounds high, but if its $20 versus $10, does that justify $350?

sokogear OP

 $350 sound fair

SMP (switchmode)
https://ibb.co/syZLpCj

Linear LMP
https://ibb.co/xGQVK29

Cheers George

Most of these small audio manufacturers have commensurate small volume. To that end, they are paying quite a bit for components, and an arm and a leg for assembly. What you can build 100,000 of for $10/each, can cost $100(or more)/each, to build 100.

I wonder what that represents in actual dollars. Double sounds high, but if its $20 versus $10, does that justify $350?

Looking forward to hearing how it turns out. 

Thank you all for your contributions. I did my science project and since it came with no instructions, I did speak with Ron Sutherland a couple times during the 90 minutes or so swapping the board and power bridge. Second time would probably take 15 minutes. The guy is so refreshingly nice and patient, I can't recommend him highly enough for anyone looking for a phono stage with the features needed at a price point anyone is considering. They get very good reviews. He will service any of his equipment regardless of where or when it was purchased, and is happy to do so. He just wants people to enjoy the fruits of his labor and is honored to have his products as part of his customers' systems.

When I connected the unit, the upgrade did not have anywhere near the same impact it did when the phono stage was connected the first time (as expected), but I could hear a little bit more in the bass, more so for jazz than rock, but this is for only a small sampling of records.

As long as it does not hurt the sound, I am glad I did it. If it becomes more noticeable, I'll post again.

The LPS was recently added as an option and Ron told me he has only sold a handful of upgrades (new Insights are often optioned with the LPS straight out of the factory). He doesn't charge labor to do it, so unless you like working in very tight spaces, are dexterous,  and have patience, I would let him do it. He can count on one hand (I think it was 3) the number of his customers that did it themselves like me. He was the one who told me I could do it and what would be involved and he was right on the money. Great guy.  

That price for a good linear supply is really a great deal IMO. Plus, the ability to help support what I believe to be a very excellent designer.

Forgot to mention... it is exactly the same power supply as in his $3800 Little Loco model, so I do think it is a good deal, which is why I bought it.

It takes up as much space as the main board, so yeah $350 is more than justifiable.

It only has value to me though, if I can hear it, but still it's nice to have. I am sure I will hear more and more improvement.