• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). There are daily reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Sutherland KC Vibe MK2 Phono Stage Review

Rate this phono stage:

  • 1. Poor (headless panther)

    Votes: 17 14.5%
  • 2. Not terrible (postman panther)

    Votes: 46 39.3%
  • 3. Fine (happy panther)

    Votes: 47 40.2%
  • 4. Great (golfing panther)

    Votes: 7 6.0%

  • Total voters
    117

egellings

Major Contributor
Joined
Feb 6, 2020
Messages
2,199
Likes
1,653
Have you not understood the issue here or you are just going with the manufacturers "vibes"? How do you expect a battery operated amplifier be better than the one that is operated at 48VDC?
My impression on rail voltage for a phono preamp is that it does not need to be all that large. An output swing of say, 2Vrms would likely overload the following line stage. 48Vdc rails are simply not needed to supply that, although they certainly would work in that application. Again, it's like asking for a drop forge when all you need is a tack hammer.
 

Angsty

Major Contributor
Forum Donor
Joined
Apr 11, 2020
Messages
1,124
Likes
1,426
Location
Southeastern U.S.
Interesting company. I never heard of them but I'd like to see reviews of the products higher up in their lineup. The Vibe MK2 is their entry level product. Their top of the line model is only $4000--which for this type of product is reasonable if it performs significantly better. The styling is a little simplistic but their products are made the USA so they need to cut costs somehow. I like the aesthetic of their higher end products.

If their "Insight" model toped the review chart, I wouldn't mind putting down $1400 to get that level of performance.
Lots of handwringing here about the headroom performance. I own a Sutherland Insight which I had not gotten around to submitting for ASR testing. The easiest way for Amir to address the headroom performance question would be to call Ron Sutherland. He provides the support for his products. He’s a gentleman and an engineer’s engineer, to boot - a physicist by training. I talked to him briefly earlier this year. If there is an anomaly in the headroom, I’m sure Ron can speak to it without BS.
 

sarumbear

Master Contributor
Forum Donor
Joined
Aug 15, 2020
Messages
5,206
Likes
4,688
Location
Southampton, England
The easiest way for Amir to address the headroom performance question would be to call Ron Sutherland. He provides the support for his products. He’s a gentleman and an engineer’s engineer, to boot - a physicist by training. I talked to him briefly earlier this year. If there is an anomaly in the headroom, I’m sure Ron can speak to it without BS.
I expected for the manufacturer to "call" @amirm, not the other way around.
 

Angsty

Major Contributor
Forum Donor
Joined
Apr 11, 2020
Messages
1,124
Likes
1,426
Location
Southeastern U.S.
My impression on rail voltage for a phono preamp is that it does not need to be all that large. An output swing of say, 2Vrms would likely overload the following line stage. 48Vdc rails are simply not needed to supply that, although they certainly would work in that application. Again, it's like asking for a drop forge when all you need is a tack hammer.
My understanding of the 48V power supply is that 1) the designer uses multiple LC filters in the power supply to reduce ripple so a good deal of voltage is lost in those stages, 2) the same 48V power supply is also used in higher end products, which streamlines his parts bin.
 
Last edited:

Angsty

Major Contributor
Forum Donor
Joined
Apr 11, 2020
Messages
1,124
Likes
1,426
Location
Southeastern U.S.
I went back to look at the Cambridge Solo review and the clipping test only appears to test 1 frequency. The newer reviews show multiple frequencies tested for clipping. Assuming I am not missing something, doesn't this invalidate clipping comparisons to a certain degree? I like that there is more data, but as the testing evolves the older tests don't compare as well against the newer.
I agree with you, Bob.
 

pma

Major Contributor
Joined
Feb 23, 2019
Messages
3,291
Likes
6,853
Location
Prague
I went back to look at the Cambridge Solo review and the clipping test only appears to test 1 frequency. The newer reviews show multiple frequencies tested for clipping. Assuming I am not missing something, doesn't this invalidate clipping comparisons to a certain degree? I like that there is more data, but as the testing evolves the older tests don't compare as well against the newer.
It strongly depends on circuit schematics, circuit design. The phono preamp clipping may be completely independent of frequency or it may strongly depend. It is up to the reviewer to make the appropriate test.
 

Bob from Florida

Addicted to Fun and Learning
Joined
Aug 20, 2020
Messages
713
Likes
619
My impression on rail voltage for a phono preamp is that it does not need to be all that large. An output swing of say, 2Vrms would likely overload the following line stage. 48Vdc rails are simply not needed to supply that, although they certainly would work in that application. Again, it's like asking for a drop forge when all you need is a tack hammer.
Lines stages typically either directly couple to your volume control or stepped attenuator or do so through a buffer. The attenuated signal then connects to the gain stage. This gives you the ability to adapt to a wide range of input levels - adjust your attenuator to match. The phono stage either has enough overload margin not to clip on peaks from scratches or has to have a quick recovery from the clipping action. Ideally has both qualities. Too much feedback is bad for clipping recovery, too little has problems driving the next stage for example. Thinking in terms of 2 or 4 volt levels is digital thinking. Analog is not limited in output level like the outputs of DACS.
 

Angsty

Major Contributor
Forum Donor
Joined
Apr 11, 2020
Messages
1,124
Likes
1,426
Location
Southeastern U.S.
It strongly depends on circuit schematics, circuit design. The phono preamp clipping may be completely independent of frequency or it may strongly depend. It is up to the reviewer to make the appropriate test.
I interpret the point Bob is making is that the testing methodology has changed such that it's no longer an apples-to-apples comparison from the old Solo review to the new Vibe review. Neither test is invalid individually, but the comparisons between the two have somewhat less validity unless you limit the clipping comparisons only to 1kHz. Even then, the graphs in the two reviews have different units: THD+N Ratio in percentage versus dB. Convertible, of course, but harder to line up side by side.
 

Angsty

Major Contributor
Forum Donor
Joined
Apr 11, 2020
Messages
1,124
Likes
1,426
Location
Southeastern U.S.
Lines stages typically either directly couple to your volume control or stepped attenuator or do so through a buffer. The attenuated signal then connects to the gain stage. This gives you the ability to adapt to a wide range of input levels - adjust your attenuator to match. The phono stage either has enough overload margin not to clip on peaks from scratches or has to have a quick recovery from the clipping action. Ideally has both qualities. Too much feedback is bad for clipping recovery, too little has problems driving the next stage for example. Thinking in terms of 2 or 4 volt levels is digital thinking. Analog is not limited in output level like the outputs of DACS.
True. I was also looking at the gain and thinking if 40 dB might be more appropriate for this testing protocol versus the recommended 45 dB. I know if I thought I was getting distortion on a variable gain phonostage, I'd consider dialing back the gain. Not discounting the measurements, but putting them in context of the real-world application.

What's interesting to me is that the Insight sounds to me more "laid back" and a bit less dynamic than my Bryston phonostage, which is stated to be "overload proof". Given the flat frequency response of both the Vibe and Bryston (in prior measurement elsewhere), I wonder how much of that observed behavior might be due to how it handles high-level input signals. The Vibe and Insight have similar circuit designs, but not exactly the same. Here is where "insight" from the designer could be useful.
 

Angsty

Major Contributor
Forum Donor
Joined
Apr 11, 2020
Messages
1,124
Likes
1,426
Location
Southeastern U.S.
The build costs of this amp are below $ 200.- when built in small quantities so that's quite a markup.
I see a $895 retail price for this unit. It probably costs the retailer about $450 to buy and the manufacturer about $225 to produce in Kansas. Seems about right, but it would indeed likely sell for a lot less if it were sold directly from the manufacturer.

According to Upscale Audio, "Most everything in the KC VIBE comes from that SAME stock of premium parts [as other higher-end Sutherland phonostages]. They only had to add 5 new parts bins to build the KC VIBE circuit boards.
  • 2 new values of polypropylene film capacitors (but still Wima brand, imported from Germany)
  • 1 new value of electrolytic capacitor (premium, high reliability, very low impedance)
  • 2 new op amps (both audio specialized Burr-Brown)
  • Printed circuit board (same supplier and specs as more expensive models)
  • Metal work – cover and base (Same supplier and specs as more expensive models)"
The Mk2 version here was modified from the Mk1 with a new case that appears to be the same as for the TZ Vibe and the 20/20 outboard power supply.
 
Last edited:

sarumbear

Master Contributor
Forum Donor
Joined
Aug 15, 2020
Messages
5,206
Likes
4,688
Location
Southampton, England
Why? How would he know to call?
Im surprised with your question. Any manufacturer is expected to follow the reviews of their products on major publishers, which ASR is one. If they don’t care about their market how do we know that they care for their customers?
 

Angsty

Major Contributor
Forum Donor
Joined
Apr 11, 2020
Messages
1,124
Likes
1,426
Location
Southeastern U.S.
Im surprised with your question. Any manufacturer is expected to follow the reviews of their products on major publishers, which ASR is one. If they don’t care about their market how do we know that they care for their customers?
Typically, an audio reviewer requests a review unit from a distributor or manufacturer. The Vibe unit tested here was sourced from a reader. Most audio reviewers/reporters do engage in some dialogue with the manufacturer when publishing a review; ASR operates on a different principal in general, but has done so before.

Sutherland probably employs about 5 employees; most of those would likely be production workers. I'm fairly certain that small boutique shops like Sutherland don't spend their days scouring the Internet for every possible mention of their products. ASR has never reviewed a Sutherland product before; ASR reviews few high-end phonostages which are Sutherland's specialty. Most ASR readers would be disinclined to spend over $1000 on a phonostage, per the comments I've seen.

So, no, I would not expect Ron Sutherland to have heard of ASR. Even if ASR has a wide base of online readers, it has had zero impact on his commercial interests up to this point.

But more to the thrust of the question, why would it be so odd to expect that Amir might want to call Ron Sutherland? If the point of the site is scientifically based inquiry of audio products, I'd think such a call would further the interests of everyone involved rather than just assuming that Ron would know that ASR has just reviewed a reader-owned product. In particular, I think the dialogue would be enlightening regarding the test protocols ASR uses for phonostages, which have been a moving target over the past few years.

Ron's a nice guy, a thoughtful and careful engineer, and a well-established designer in his niche, but I do not presuppose that he's thinking about what ASR has to say right now.
 

sarumbear

Master Contributor
Forum Donor
Joined
Aug 15, 2020
Messages
5,206
Likes
4,688
Location
Southampton, England
Typically, an audio reviewer requests a review unit from a distributor or manufacturer. The Vibe unit tested here was sourced from a reader. Most audio reviewers/reporters do engage in some dialogue with the manufacturer when publishing a review; ASR operates on a different principal in general, but has done so before.

Sutherland probably employs about 5 employees; most of those would likely be production workers. I'm fairly certain that small boutique shops like Sutherland don't spend their days scouring the Internet for every possible mention of their products. ASR has never reviewed a Sutherland product before; ASR reviews few high-end phonostages which are Sutherland's specialty. Most ASR readers would be disinclined to spend over $1000 on a phonostage, per the comments I've seen.

So, no, I would not expect Ron Sutherland to have heard of ASR. Even if ASR has a wide base of online readers, it has had zero impact on his commercial interests up to this point.

But more to the thrust of the question, why would it be so odd to expect that Amir might want to call Ron Sutherland? If the point of the site is scientifically based inquiry of audio products, I'd think such a call would further the interests of everyone involved rather than just assuming that Ron would know that ASR has just reviewed a reader-owned product. In particular, I think the dialogue would be enlightening regarding the test protocols ASR uses for phonostages, which have been a moving target over the past few years.

Ron's a nice guy, a thoughtful and careful engineer, and a well-established designer in his niche, but I do not presuppose that he's thinking about what ASR has to say right now.
I respectfully disagree on your premises.
 

Angsty

Major Contributor
Forum Donor
Joined
Apr 11, 2020
Messages
1,124
Likes
1,426
Location
Southeastern U.S.
I don't see how that would be a benefit. It would still be an unbalanced connection even if it was differential. To get the benefit, it needs to both balanced and differential. A phono socket is unbalanced, even if the ground is floating.

S
The Phono Loco is a transimpedance phono amp that is suitable for only MC cartridges. The tonearm has to be wired for balanced signals to work with the Phono Loco. The Little Loco is also transimpedance, but utilizes a work-around that allows for a regular unbalanced RCA input.
 

juliangst

Senior Member
Joined
Dec 11, 2021
Messages
380
Likes
310
Dumb question: With that low distortion will the vinyl or the turntable be the limiting factor here?
How much THD+N would a '1kHz vinyl' have when paired with a high quality turntable and phono amp like this one?
 

LTig

Major Contributor
Forum Donor
Joined
Feb 27, 2019
Messages
4,556
Likes
7,360
Location
Europe
Dumb question: With that low distortion will the vinyl or the turntable be the limiting factor here?
Yes.
How much THD+N would a '1kHz vinyl' have when paired with a high quality turntable and phono amp like this one?
It depends on the vinyl. I would not expect less than around -60 dB.
 

MrOtto

Senior Member
Joined
Nov 4, 2020
Messages
312
Likes
239
Shouldn't Cambridge Alva Duo be on top of the chart for Phono Pre-amplifier chart?
 

pvehling

Active Member
Joined
Jul 19, 2019
Messages
169
Likes
136
Location
USA
Shouldn't Cambridge Alva Duo be on top of the chart for Phono Pre-amplifier chart?
I think that was measured in a different way back then compared to the standard he does now, but it should still be up near the top anyways
 
Top Bottom