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Mark Levinson No52 Stereo Preamplifier Review

https://hometheaterhifi.com/reviews/...lifier-review/

I think the short answer is yes. It’s been a while since I’ve listened to a 32 but I’d sum it up like this ... the 32 had an incredibly low noise floor, great detail, a very good sense of space between instruments, great bottom end extension and wonderful timbral reproduction. The 52 does all of that at about the same level or a tiny bit better but where it really excels is in the area of 3 dimensional holographic soundstage reproduction. Listen to the first three tracks of Becks Morning Phase and you’ll be convinced you’re in the recording not listening to it. Robert Len’s Hope DSD128 recording will do the same thing. I can list many others but the 52 renders a 3 dimensional soundstage in a way that usually is reserved for tube preamps. Now...I’m not saying it generally sounds like a tube product because it doesn’t ... just has the sense of space and presence we usually associate with that. Combine that with everything else that it does so well and you have a preamp that is simply in another league than most and embarrassed by none regardless of price. If you like the 32 the 52 is even better. One note though ... it does take its sweet time breaking in from new so you have to be patient. Think 1000 hours to get the very best out of it. I think it really is the best ML has ever built.

George

thanks, this looks like a really nice, informative and friendly forum

thanks for the reply Gadawg.
I do believe you, but I am quite puzzled by the changes in design from the 32 to the 52.
As a former audio engineer I designed many audio products, some really expensive ones. This all stopped in 2005, but my love for audio never disappeared and since 2 years I am fully addicted to great sound and the stuff that comes along with it.

In 2004 I compared the No32 with my latest design, a two box pre-amp for an established high-end audio company (also listed in the manufacturers forum here at AA). I believe it retailed for around $20k. The cost was also substantial.
We compared it to the No32 and although the differences were not day and night, the 32 just was a better amp.
As my free-lance design work stopped due to more work with my day-time job I never got to the bottom of it, but the no 32 always kept in the back of my mind as "the" pre-amp.
When the 52 came out I was less impressed with some of the design choices.

As I am new here I am not yet allowed to post a new thread, but when that happens I will do so with a (technical) analysis of what I think the differences are. If the AA community agrees the 52 is better than this could become interesting reading and again proof that great sound can not always be explained by technical choices.

Cheers.

Some of the technical choices were puzzling to me as well like the use of op amps rather than discrete outputs but like the Esoteric CD players I think the magic is in the implementation of the parts just as much as it is the parts chosen. Many companies use the AK chips but just can’t match what Esoteric is able to do with them. ML went all discrete in the their new preamps but they just can’t quite do what the 52 does. Now ... I’m thinking they will upgrade the 52 soon and maybe take the advanced design of the 52 and go discrete. Might be even better. Just a note I think if you subscribe you can post immediately. Glad to meet you and looking forward to hearing more about your thoughts technically.

George

Thanks George,
I am glad I wasn't the only one who questioned their choices.
There is a full written analysis waiting to be posted, but I need to reach 10 posts .... !!!!
Peter

Peter,

So I went back tonight and did some reading on the 32 Reference as its been a long time and my memory isn’t what it once was ... I was surprised to find that it made use of the instrumentation quality op amps like the 52. Actually the op amp boards look very similar to what was in the 326s. Both were a substantial upgrade over the 380. If you go back real far you can find units that used actual transistors mounted on heat sinks but that appears to have changed in the later Madrigal era. Harmon continued that up until now and I’m guessing will bring out new Ref product that follows their new design directions. I’ve owned a 380, 326 and now 52 Ref and the 52 is the best but the 32 is very very good and if you find one in great condition you’ll have an excellent unit at a bargain price. I did listen to a 32 but it’s been a while

In fact ... the 52 seems to be more of a refinement of the 32 rather than re-invented. There are a ton of open box pictures on the web of both units and there are a ton of design similarities between them. One of the biggest differences was the material for the circuit board which I believe stopped being available at some point on the 32. I can only say I wish they had ‘refined’ the 33H rather than produce the 53’s! I’m betting the next Ref amp isn’t too many years away now that the 536s bests the 53s in many areas IMHO.

George

George,

I have a schematic of the 32 (most pages at least) and it is a very complex unit.
Especially the multistage power supply. The actual schematic of the audio path is quite straightforward. and all happens on the lower board of the actual amp.

I think "refinement" is quite a good word for what happened. I do believe that the 52 is substantial lower in cost to build.
Peter

So to actually respond on the topic of this thread.
An alternative (because of budget) would be a 326s for me. They appear a bit more often on local eBay. What I can see is that indeed some design elements are copied from the No32. However the power supply doesn't come close. This doesn't mean that it is no good, but it does not have the isolation the 32 has. In my opinion a 52 and 32 will sound good no matter how poor the AC is, but a 326s needs a clean supply. And the rest of the equipment still does as well as I have not seen any other component (source or power amp) that uses this kind of isolation from the mains supply as the 32 and 52 have.
In my situation with fully isolated balanced AC mains (pos and neg 115V AC) the 326s could perform quite well.

The discrete designs from the Madrigal area you refer to is the 26 for instance. I borrowed that unit once and reverse engineered it to get the schematic. Not a design I would like to use, but for its days quite a daring design. unbalanced in the middle and a balanced to unbalanced input option with just a discrete inverter amp to get balanced out.
But these amps are getting quite old now.