MBL Noble Line N11 line preamplifier

During the four years that I've reviewed for Stereophile, I've had the privilege of evaluating products from some of the world's best-known audiophile companies: Audio Research, Bel Canto, CH Precision, dCS, D'Agostino, Dynaudio, EMM Labs, Jadis, Krell, Nordost, and Wilson, among others. But one long-standing manufacturer whose exhibits at audio shows invariably inspire ecstatic reports, Germany's MBL, has remained outside my purview.

It thus came as a delightful surprise when MBL North America's Jeremy Bryan informed Jim Austin and me that the MBL N11 solid-state line preamplifier ($14,600) was available for review. Part of the company's middle-level Noble Line of electronics, the N11 differs from the Reference Line's 6010 preamp in one key respect: the notion—specifically, designer Jürgen Reis's notion—of how it should sound.

In a series of Skype interviews, Reis explained, "The lines don't differ very much in measurements. In the 35 years I've developed preamps, I've had a lot of experience with different audiophiles. I have spent a lot of time at the homes of Reference Line customers, and I know their taste, how they've constructed their living rooms, and the sound they prefer. The typical Noble Line customer has a different living room and different taste. Therefore, the answer to the question, 'Which is the better preamp?' is, 'The preamp that works the best for you in your room.'

"I know the sound of every resistor, every capacitor—everything. I know what tonal balance will be created when I mix this with that. So, when I started to develop the N11, I had a sound in my head. I made the schematic, optimized the layout to measure well, and then began listening and tuning with small parts. I adjusted the capacitor contacts, chose the correct parts for the desired sound, and determined what kind of silk screen on the printed circuit board would create the sound that would best fit Noble Line target customers.

"Some of my work involved tuning the power supply. It may come as a surprise to learn that you can change tonality without even touching the signal path, because the signal originates from the power supply. The impedance curve of the N11's power supply is absolutely homogenous from DC to 200kHz, which creates a very balanced sound. I also tuned the resistors for the voltage gain, using a mix of carbon and metal resistors to create a neutral balance. There are a lot of preamps that claim to be 'neutral' or 'in balance,' but there are different shades of 'neutral.' If you have a tube preamp, for example, 'neutral' is at a different level than solid-state; it's not better or worse, but it is different. It took a lot of work to find the tonal balance I like a lot that measures well, with low noise, and fits very well in the Noble Line."

620mbl.top

"I won't tell anyone that the N11 is the 'best' preamp for their system, but I will say that it matches perfectly with other Noble Line components, and its sound is different than the sound of the preamp section of the Noble Line N51 Integrated amp. The goal is to choose components that work well together to achieve optimal synergy. They don't have to be the 'best' products or all from the same company, but they have to work optimally with your other components, your room, and your taste. This is the biggest challenge for a dealer: To get to know a customer well enough to be able to find the best combination for them."

"Unity Gain"
A unique aspect of the N11 is its "Unity Gain" feature, which can be engaged or disengaged easily via the preamp's control panel or remote control. "When you have components whose specifications are within the normal range, eg, a digital source with an analog feed of around 2V and a power amp that delivers its maximum power around 2V, then it makes the most sense to have a preamp or control unit that works best at 2V," Reis told me. "If you set our preamp to Unity Gain, the music flows the easiest way, without impediment, from the DAC to the power amp. This gives the highest transparency and lowest distortion."

This is, Reis confirmed in a series of emails, a matter of reducing the preamp's gain so that the signal isn't amplified excessively and then attenuated. With "Unity Gain" activated, a 2V input signal—full-scale according to the CD Standard—results in a 2V signal to the power amp with the N11's volume set to 70. Two volts is close to the input voltage at which most power amplifiers achieve their maximum power: max-in = max-out, or vice versa, depending on your perspective.

While 2V is the CD Standard, many digital source components have full-scale output that's as much as several volts higher—and yet most preamps have more gain than the N11 with Unity Gain activated, which means more attenuation is needed to achieve the optimal volume level. "By unnecessarily reducing the level and then amplifying it, dynamics and resolution are lost, while noise and distortion increase—factors that one desperately wants to avoid with high performance, high resolution systems," Reis told me. Of course, the N11 can also be used, with Unity Gain on or off, with source components that don't adhere to this standard—just reduce or increase the volume setting to compensate—but in that case, the system is less than perfectly optimized.

A system with standardized input voltage and Unity Gain mimics systems used in mastering studios—first by better exploiting a system's available gain and second by allowing output levels to be calibrated. "When you set a stereo system at the same volume level as a mastering system, a unity-gain preamp will bring you the closest to what the mastering engineer heard," Reis told me. "In my mastering setup, I follow the guidelines set down by Bob Katz in his book, Mastering Audio: The Art and the Science. Each channel should measure 83dB average; this is the level where, when music is played back, it sounds as it sounded during a mastering session conducted by a certified mastering engineer." (footnote 1) In such a system, if the track you're listening to has a dynamic range rating of DR14 (footnote 2)—very wide—the peak signal level will be 101dB, which is also optimal." (footnote 3)

In the green room
Some may not consider my opinions on visual aesthetics worth the price of beans—especially with beans being hoarded during the COVID-19 pandemic. Be that as it may, when it perches on the top left shelf of my Grand Prix Monza rack, the N11's unique black-and-silver profile cut a handsome figure in the company of dCS's Rossini DAC, Clock, and CD/SACD Transport; EMM Labs' DV2 integrated DAC; Roon's Nucleus+ with the HDPlex linear power supply; two Nordost QX4 noise suppressors; and AudioQuest's Niagara 5000 power conditioner.

620mbl.whitegold

Besides its Unity Gain option and unique remote control (round, heavy, well-considered), the N11's features are decidedly up-to-date. Its front is dominated by a 5" color TFT display, easily read from 12' away, that can be used in place of the remote to access the menu, display options, and control basic functions. Also on the front panel are a standby button and six "smart keys"—function buttons—three on each side of the display. These easily depressed buttons—in the sense that they don't require much force, not that they have a tendency to be morose—can, among other things, activate or deactivate inputs and outputs, set maximum volume at power-on (50 is the default), restore factory defaults, turn Unity Gain on and off, and mute or unmute. As your hand approaches the N11, a sensor automatically switches the screen from playback mode to interface mode and displays the settings available with the soft keys; otherwise, the screen displays the volume level, which input is activated (RCA or XLR), which outputs are deactivated, and whether Unity Gain is engaged.

On the rear, the N11 has five pairs of RCA (single-ended) inputs, two pairs of XLR (balanced) inputs, and one set of inputs that can be, optionally, either an RCA pair for a moving-coil phono cartridge or a third XLR pair; the review sample had the XLR pair. Five pairs of variable outputs are divided in two groups, each with a mixture of RCA and XLR. There are two fixed outputs, one RCA and one XLR. There's a ground terminal for a turntable, two MBL SmartLinks (for other MBL products, which I didn't have), an Update interface (which I didn't use), and your basic fuse bracket/IEC inlet/power switch. The top has an illumined circular logo that doubles as a brightness control for the display. It's all laid out well and makes sense.


Footnote 1: Many readers know that the ear's sensitivity depends on frequency—pitch—and that this dependence varies with volume. So the tonal balance of music sounds different at different volume settings.

Footnote 2: Reis is referring to the "crest-factor" dynamic-range scale from the Pleasurize Music Foundation and implemented by MAAT—not the D128 standard whose ratings are displayed, for example, in Roon. MAAT has a tool you can buy for measuring this dynamic range, here.—Editor

Footnote 3: Ideal calibration of volume-vs-input level also depends on having an ideal combination of amplifier gain and loudspeaker sensitivity.—Editor

COMPANY INFO
MBL Akustikgerate GmbH & Co. KG
US Distributor: MBL North America, Inc.
217 N. Seacrest Blvd. #276
Boynton Beach, FL 33425
(561) 735-9300
ARTICLE CONTENTS

COMMENTS
Bogolu Haranath's picture

Some preamplifiers like the Parasound JC2 BP come with input gain controls ...... Also, some power amplifiers like the Parasound Halo JC-5 come with input gain controls ....... Do those pre-amps and power amps work similar to the 'unity gain' controls like the MBL N11 pre-amp? ..... May be JA1 could shed some light on this matter :-) ........

Bogolu Haranath's picture

Distortion levels 0.0005% ..... SNR better than 20 Bits :-) ......

Shahram's picture

I mean seriously. Chrome Gold? Yuck. I guess that appeals to the 70 year old audiophile.

Jason Victor Serinus's picture

And adds nothing of value. For the record, the version I reviewed, on which I based my visual assessment, was black and chrome.

Long-time listener's picture

You're right Jason. Ageism, like racism, is ignorant and offensive.

Having said that, putting a single knob or dial in the middle of a component's front face is pretty much the definition of design dullness (like the Cambridge Audio Edge). And MBL has made it not only dull, but ungainly, and gratuitously bling-ey as well. Not good moves.

And here we have a $14,600 pre-amp that you can't be sure will work well with whatever your DAC is. What a wonderful world we modern audiophiles are living in!

Jason Victor Serinus's picture

First and foremost, thank you. Ordinarily I do not call people out for stuff. But you're right on. These divisions of rank and privilege based on age, race, gender, sexual orientation, nationality, religion / spiritual path / or lack thereof, country of origin, and all the rest must be addressed and named for what they are.

We all have our differences in taste and aesthetics, which I respect. Even if you think this preamplifier is ugly as sin, you are not my enemy, and neither of us need defend our opinions. As with many products these days, the N11's front is minimal because, unless you use the remote, all functions are controlled by that one knob and six buttons, and displayed on the big screen. Some would say designs of the nature beat 4 knobs, 8 toggle switches, and the like, but others would not. Diversity is what makes the world go round.

However, the issue of what preamp will or will not work well with your DAC or amps or speakers or whatever is one of system synergy. System synergy is always an issue with audio components, whether audiophile quality or not. It's just that when we have little money to spend-there was a time when all I could afford was a used turntable, basic cartridge, used $25 headphone amp, and some aging and not very costly Sennheiser headphones-many of us see ourselves as "beggars can't be choosers." Undoubtedly there were more harmonious pairings of $25 or $30 headphone amps and Sennheiser or Koss or whatever headphones out there, but I never even knew that a simple change of one or the other could make an audible difference. When it comes to naïveté, I was "in the garden," so to speak, albeit not the one that Joni Mitchell sang about in "Woodstock."

There is one thing that I find dismaying about the comments so far. People have focused on words, attitude, income, cost, and looks. But no one seems to have paid much attention to this:

"I concluded my measurements of the Benchmark LA4 preamplifier in the January 2020 issue by writing 'Benchmark's LA4 is the widest-bandwidth, widest-dynamic-range, lowest-noise, lowest-distortion preamplifier I have encountered.' Its performance on the test bench reveals that MBL's N11 now takes that crown.—John Atkinson"

Although, subjectively speaking, the N11 may not be the most neutral or mind-blowing preamp I have ever auditioned, it is the best-measuring preamp that John Atkinson has ever had on his test bench. We're talking about four decades of testing. This is a major component, and worthy of consideration as a Best of the Year. John wasn't as impressed, measurement-wise, with the D'Agostino Momentum HD preamp I reviewed, but I consider it another worthy contender for all the reasons I detail in that review.

This, ultimately, is the reason why my reply is so long. This preamp is worthy of consideration by anyone who can afford it and who likes its looks and sound. It could very well be "the" preamp for many Stereophile readers.

One more comment. In the last two years, I've reviewed products that cost between $600 and $52,000. I kinda lose track of what review will be published in what issue,, but I think that my next product review is of a DAC that costs 1/4 - 1/3 the price of the MBL N11 (depending upon whether you purchase the DACs optional outboard power supply). I like the sound of that DAC a lot.

By nature, I do not automatically resent people who have more $ than I do, who drive nicer and newer cars than my '94 Toyota Corolla DX, or who retired when they were 30 years younger than I am now. I do have strong feelings about people who make their money by exploiting others, but that's a completely other issue in my book. I know people who work just as hard or far less hard than I who nonetheless make or who have made far more money through honest labor that serves humanity's highest good. Some of those people can afford and care about the five-figure products I sometimes review. I wish them all the happiness in the world.

Stay safe, my friend, and be well. And I say that to everyone, even my harshest critics and those who are contributing to the spread of COVID-19.

Long-time listener's picture

I appreciate all that you say. As far as whether I "automatically resent people who have more $ than I do," I don't. What I resent is that money seems to dictate what is popular, or even ideologically or politically correct, with respect to stereo stuff -- such as tone controls or balance controls -- and that leaves a lot of us out of the game. Tone controls for example are prevalent on cheap receivers, but rarely, if ever, on expensive equipment, and there is no justification for that in audio terms. Those of us who want to use them (I use then rarely, but occasionally they're very helpful) of course understand that there may be some tiny price to pay in terms of distortion or noise, but we consider it worth it. Yet the idea of "signal purity" is used to reject tone controls even by the same kind of people who put up with high levels of distortion in tube equipment. These things are not dictated by consumer needs, but by fashion, or ideology, or audio political correctness, and it's obviously the high end that is dictating those things, not the mass market. There actually was one pre-amp in recent years, by Luxman, that did have wonderfully versatile tone controls, and I would like to buy it but at $5,000, I can't really afford it (and I don't like messing with tubes). Actually I could afford it if I hadn't already bought the $4,000 NAD M32 which came "highly recommended" in Class A by John Atkinson. After buying it I found that (in addition to the tone controls I wanted) it had hard, brittle sound that made it fatiguing and unlistenable to me. So now I know that I can't trust Atkinson's ears and I ignore that aspect of his reviews, even if I find his measurements invaluable and I read them religiously. I applaud the fine measurements of the MBL. And resentment of money isn't the issue here. It's the stupidity and narrow-mindedness that makes people like me feel left out that creates resentment. And the casual recommendations of reviewers who don't really care about items that aren't in the stratospheric range of components they normally listen to and they don't care to live with them long enough to find out how they really sound. (I know what you're going to say in his defense -- whatever.) LTL

Jason Victor Serinus's picture

Hello L-t L,

Please understand that when I was discussing resentment on the part of people who can afford equipment we can't afford, I was not thinking about you personally (or impersonally, since I have no idea who you are). I was making an observation about a recurring trend I see in the comments section.

Your comment about tone controls is interesting, because I just reviewed an integrated with tone controls. It will take two months for that review to appear here, and less for it to appear in print (and available, along with recording reviews and comments and letters that are not available online, to subscribers for a whole $12.95/year). I didn't like the effects of those tone controls at all. I'm rather relieved that in my discussion, I didn't invoke "signal purity." The thought wasn't even in Ms. Ivory Snow's mind. I just know what I heard.

I find John's ears extremely acute. I wouldn't be surprised if his recent Esenvalds recording, to which I gave a RotM and which Gramophone praised highly for its engineering, scores a Grammy nomination in the engineering department. It is possible, however, that the NAD was a far better match for his system than for yours. This could lead to a whole discussion of the "absolute sound" of components. But a simple mention of that myth is more than sufficient, as far as I'm concerned.

Time to go running before the rain hits. Be well,
jason

Long-time listener's picture

Good for you. I think he needs to be a little more thoughtful in his reviews, and ask himself if what he is hearing is something he would really want to live with himself. Recommending the Aerial 5T for Class A, after describing how difficult it was to set it up to get good bass response -- and how he did that only by ignoring manufacturer placement recommendations, and only by using a $20,000 amp known for its bass control -- is one example. Also, I tried the NAD M32 with three different sets of speakers (one being his "Class A" Aerials), so sorry, it's not just that it was a poor match for my "system." With each of the three it sounded hard and digital relative to a (less expensive) solid state amp with the same power rating.

And again you express your dislike for tone controls. In every single review they are either ignored, or disparaged. Reviewers always say something like, "And then I got out my Reference Recording pressing of Bruckner's 9th by [fill in the name of an orchestra and conductor not known for playing Bruckner, since it's not really the music that counts here], which allowed me to hear the delicately filigreed highs..." Duh. Of course we never see: "And then I got out my 1939 Toscanini Beethoven 9th (or my 1958 Miles Davis "Miles Ahead," or my early '80s digital Karajan Bruckner), where the wonderful tone controls of the Luxman allowed me to tame the steely highs, and to hear more realistically proportioned weight in the bass." No, that will never happen. You'd rather "hold your ears and grit your teeth," or however it was that you once described it. That's not the audiophile experience all of us want to have. But we often don't have much choice in the matter.

Bogolu Haranath's picture

May be JVS could review the two chassis flag-ship tube pre-amp, Mcintosh C1100 ($13,000) ...... Hi-Fi News measured 0.00009% - 0.0005% distortion levels for C1100 :-) .......

glamanna's picture

QUOTE: // “These divisions of rank and privilege based on age, race, gender, sexual orientation, nationality, religion / spiritual path / or lack thereof, country of origin, and all the rest must be addressed and named for what they are.” //

You read all of that into a comment about styling of an audio component? The comment you condemn as somehow “divisive” is actually an accurate assessment of the audio component’s 1970s look. So now saying that a house is “turn of the century” is akin to lynching minorities or pushing grandma over the cliff?

Do you really believe this? Because if you do, you are the one perpetuating all of this “isms” you listed and showing that they exist primarily between your ears. Certainly not in reality.

Ask yourself who benefits from the feigned victim hood of manufactured divisiveness. Victim hood is Big Bisiness and the cornerstone of Fascist and Marxist revolutionary theory. Just saying ….

glamanna's picture

Looks like a discoteche threw it up.

tonykaz's picture

"purview" is 'Scope of Influence'

Jason Victor Serinus's picture

There is a wider definition of "purview." You may want to look at this one: https://www.merriam-webster.com/dictionary/purview.

tonykaz's picture

Purview is legal terminology typically associated with being outside the limits of your Job, authority or knowledge. i.e. a plumber offering legal advice.

Considering that the MBL person did the majority of the important parts of the review, this MBL review may very well have been outside your purview. I found his insights helpful and necessary.

Tony in Venice

ps. Oxford English Dictionary is the Standard. The 20 Volume Edition is appropriate for writers.

tonykaz's picture

"purview" is 'Scope of Influence'

Bogolu Haranath's picture

Anybody who can afford Wilsons, D'Agostinos, dCS, Nordost cables and Grand Prix Monza racks is 'privileged' :-) .......

tonykaz's picture

and a bit of a snub to lesser peer groups.

There is an implied 'Velvet Rope' divider with this sort of attitude.

-------------

MBL is super nice sounding, gaudy gear that is probably hell on the cleaning lady. The entire MBL System is Jaw Dropingly stunning in appearance and Sound Quality ( if you are "privileged" enough to be in the Same Room with it playing Lang-Lang ).

Tony in Venice

Anton's picture

1) That MBL preamp is stone cold guaranteed to match well will your Nagel prints! How’s that for synergy?

2) Anybody remember when the reference was “the absolute sound” and not comparative differences between pieces of gear? This has been a quantum shift that was discussed 40 years ago as a pathway we should be wary of. Now, we compare gear to gear.

Jason Victor Serinus's picture

Score two points for the Gipper.

Bogolu Haranath's picture

That MBL pre-amp also matches well with the round meters on the Progression amps :-) ........

davip's picture

What is the point of this 'pre'-amplifier (indeed, all line-level pre-amps)? No digital source that I'm aware of requires pre-amplification to provide levels suitable to drive a power amp, and the only source that does require pre-amplification -- a phono one -- is not catered for in this pre-amp by the absence of a phono input. So what point this device?

All the rattling about "Unity-gain" being better than a competitor's over (pre-)amplified pre-amp is a straw-man argument as it side-steps the obvious (and usually $0, unless you want to spend $5K on an auto-former) option of having no pre-amp AND better sound.

While I don't question the ability of a $14K pre-amp to show a clean pair of heels to a $140 one, I do question whether there is any digital medium of any bit- or sampling-rate whose sound quality merits such expenditure or such a wide-window as will only throw the faults of that medium into sharper relief. Spend the $14K on sealed vinyl and play it through the $140 amp -- guess which will sound better.

Let's not get into the whole "...things sounded better with the pre- in-circuit than a passive ... more 'drive' etc" thing. If transparency and fidelity are the goal, then assuming appropriate impedance matching no preamplifier is better than a pre-amplifier that isn't needed when dealing with line-level sources. In a world where companies are falling over themselves NOT to offer phono inputs, why the hell does anyone make pre-amps anymore (and who the hell buys them?!)?

And yes, it's blingy and fugly. Looks like it belongs in a financial-adviser's kitchen...

At risk of being censored, here in the UK we would say that this is kit for "wankers", irrespective of the depth of their pockets.

directdriver's picture

"If transparency and fidelity are the goal, then assuming appropriate impedance matching no preamplifier is better than a pre-amplifier that isn't needed when dealing with line-level sources."

Err... Not really for me. Maybe it is for Stereophile. I just want coloration to enhance the recording so I can enjoy the music more, unless I only listen to audiophile recordings. I don't. Obviously I'm not a neutral or absolute sound type of audiophile. Other than that I agree with your assessment of this gear. It's really ugly. At least it has good engineering and measurements.

Canadianwalker's picture

I can't help but mention the Schiit Magni Heresy headphone amplifier. It costs 100usd and has a preamp output. It is unity gain or has a switch for higher gain. It's distortion measurements are close to the MBL and does the same job, minus the switching and any phono preamp.

So basically, for digital it can do the same job. I think part of the difference in sound you are hearing between a DAC that has a volume control and using the MBL may be attributable to most of the DAC volume controls being digital. That makes for perfect matching between channels etc but you are listening to a must reduced dynamic range and possibly the low level detail is lost or distorted by comparison to full scale digital reduced in volume by a unity gain stage with an analog volume control. Something to consider anyway.

krahbeknudsen's picture

I certainly agree that the design is an acquired taste. Moreover, I would assume that most people would buy such a pre-amp for the long term. In that respect, I would be worried about the durability of the colour LCD screen and the possibility of getting a replacement after say 6-8 years.

Fruff1976's picture

That was the first thing that crossed my mind. Not only from a replacement standpoint, but the graphics alone could make it look dated. It already sort of looks like Sega Genesis.

hb72's picture

very interesting article, especially the interview. I must confess, I was not aware footers would allow as much tuning toward ones own preferences, as e.g. the choice of cables (IC & power). I always thought there is a more general i.e. uniform gain in SQ by reducing component vibrations.

Charles E Flynn's picture

From https://gearpatrol.com/2020/06/30/whats-actually-the-difference-between-a-cheap-and-expensive-stereo-receiver/ :

In general, the bigger and better the speakers you have, the more powerful the stereo receiver you’re going to need to drive them. But power isn’t everything. For example, the Yamaha R-S202BL and the more expensive Cambridge Audio AXR100 can both deliver 100-watts per channel, but what makes the Cambridge Audio AXR100 better is the build quality of the built-in amplifiers. Not only are the components higher-grade, but the AXR100 also has both right and left channels, which contributes to more accurate sound.

Jason Victor Serinus's picture

50 per channel.

Bogolu Haranath's picture

Mark Levinson 5805 integrated amp is specified as 125 WPC into 8 Ohms, by the manufacturer ..... Stereophile measurements show, it can also drive 2 Ohm loads with 370 Watts :-) ........

Glotz's picture

As I just bought the Benchmark HPA4 (line section the same as LA4), and sighed to myself, a bit deflated, but still smiling. It held the crown for a few scant months.. lol.

I love MBL designs, and I'm sure I would love silver and that white variant (I forget the color name). Otherwise a bit too blingy for my tastes.

That being said it sounds like it's a superlative preamp... though I would go with their speakers as a first purchase choice to...pretty much anything extant.

Great review as always, Jason.

X