darTZeel NHB-468 monoblock power amplifier Page 2

I'd had on repeat vinyl play the Jamie Saft Quartet's Blue Dream (Rare Noise RNR095LP), preparing to write a review that unfortunately hasn't materialized yet but will. It's beautifully recorded, as is everything produced by this label, whether recorded on tape or computer. The music might remind you of the classic Coltrane quartet, but with Saft in place of McCoy Tyner, Nasheet Waits subbing for Elvin Jones, Brad Jones for Jimmy Giuffre, and Bill McHenry for the big C.

With the NHB-468s swapped in, cold out of the box, I listened again. Big sonic change! All for the better, building on the new amp's predecessor—which had, as I described in the original review, "high-frequency cleanness and transparency combined with as perfect a high-frequency transient response as I've heard from any amplifier, all emerging from velvety-black backdrops." Back then I described the 458s' transient attacks as "neither slightly soft nor a bit too fast or tight, the latter of which can produce a hard, wiry sound that never lets you forget that you're listening to electronics, not live music." The new amps produced a sound that was immediately more supple, more liquid, and noticeably more "wraparound" three-dimensional, without turning soft. (I've heard my share of soft-sounding solid-state bores.)

Via the 468s, instrumental attacks became more delicate and nuanced. The cymbals lost a bit of unwanted etch, the bass became less mechanical (not that it sounded overtly mechanical before), and the soundstage now pushed well beyond the speakers, wrapping around and forward, producing a noticeably more enveloping sound.


The presentation gained much and lost nothing. The sonic picture floated better in space, further removed from the speaker plane than it had been previously (which was reasonably freestanding to begin with). The attack didn't soften or lose its natural edge as it became more subtle. The entire picture became more involving and less "canned."

Saft's piano became less brittle, the saxophone rounder and better balanced between reed and horn. In addition to improved attack, there was now more generous sustain and decay and an overall sense of natural musical relaxation, though instrumental attacks and overall transient performance remained the best I've heard from a solid-state amplifier. No doubt, though, those who demand more tight-fisted control and bottom-end "slam" might look toward something from Boulder, for instance.

But let me circle back: To complete that record review after months of listening, I replayed Blue Dream and heard what I've just described, then reinstalled the 458s. The stage flattened, losing the "wraparound" quality, the bass became somewhat harder and more mechanical, the cymbals lost shimmer and took on some edge, the piano produced more attack and hardness and lost the sustain generosity and suppleness. Please remember this is all by degree. It still sounded really great! But not nearly as good as through the new amps.

This was before I installed the new, replacement 50 ohm cables installed—and that's another story: After months of listening to the 468s using the original interconnects between preamp and amp, I swapped them out for the new interconnects and, as Art Dudley would say, "Holy crap"!

One of the first records I played was an original promo copy of Little Feat's Sailin' Shoes (Warner Brothers BS 2600). I've been playing this one since 1972, and I have a pretty good idea of what it sounds like, or so I thought. True, much in the system has changed since I last played it—I can't remember when—but as soon as "Easy to Slip" began, I heard the studio space appear in front of me as never before. The placement of the background singers, the guitars, everything was uncannily natural—not only in space but as individual instruments with solidity and dimensionality. The music was also more rhythmically "on time" and well organized than I've ever before heard this record sound. The record had more dynamic "slam" and control, as well as an effervescent presentational delicacy than I've likewise never before heard from it. But how much was the rest of the system contributing to this?

I was more interested in hearing records I'd been playing with the 468s connected to the preamp using the old darTZeel cable, so I went back to those, including the test pressing of Bernard Haitink and the Berlin Philharmonic's forthcoming direct-to-disc release of the Bruckner Symphony No.7, referenced in this month's Analog Corner, which I've played dozens of times over the past month using only the older cables. So let's just say: If you own darTZeel electronics connected using the older 50 ohm cable, get the new.

When I reinstalled the 458s toward the end of the review period using the new 50 ohm cables, I again played the Little Feat record, and while the sonic package was well-wrapped, it couldn't compare to what I'd heard through the 468s, especially in terms of spaciousness and attack subtlety. Well-organized though they were, the images lay flat against the speakers, hung between them almost as if on a clothesline.


Through the 458s, the direct-to-disc Bruckner produced a flatter but still holographic picture, with the massed strings sounding enduringly graceful but less liquid and somewhat harder. The three-dimensional, front-to-back instrumental layering and exceptional timbral complexity captured in this recording (using vintage tube mike preamps and mixed live on a vintage tube mixing console), especially at the conclusion of the first movement (allegro moderato), were "in the house" but scaled back in intensity and transparency.

Returning to the 468s, the Little Feat record exuded a midband richness that was missing from the 458s; instruments were more well integrated within the mix, and I heard added depth and texture in the bottom end, as well as that wider, deeper "wraparound" stage—it was immediately obvious on the first listen. Singer Lowell George was more front and center, and on "A Apolitical Blues," where the late Mr. George sings almost off-mike and more "in the room," the sense of space was intensified and made even more convincing. All gains, no losses.

As for the Bruckner, the combination of 468s and the new cable delivered even greater depth of field, three-dimensionality, and spaciousness, while intensifying string tone and textures and—especially—adding weight to the big double basses, violas, and cellos, producing the "body rush" you hear live. This is a not-to-be-missed symphonic recording and you ought to have a listen—all the more so if you're lucky enough to hear it on these amps!

The darTZeel owners I've met seem to be a happy, enthusiastic group, satisfied with their purchases and with the sound produced by whichever darTZeel products they have. Count me among them. The new NHB-468 has made me even happier. This amp does what the NHB-458 does—just better. It's got power to spare and sounds as if it's just loafing, even on the most demanding material.

I haven't seen the measurements and won't until I see the final proofs of the finished article, but I assume the distortion measurements will be good but bettered by some. I believe Delétraz is capable of reducing distortion to as low as is measurable, but he's going for something beyond measured perfection, and I think he's achieved his goal in terms of a unified, holistic, natural sonic picture.

Those who prefer in a solid-state amp greater bottom-end "grip" and iron-fisted control may want to consider a different amplifier. As I mentioned above, I think the CH Precision M1.1s produce more weight and punch on bottom, and Boulder's amps tend to have more overall speaker grip. However, in my system, the darTZeel "sound" is ideal for all musical genres: good grip on bottom, natural transient performance, plenty of air on top if it's in the recording, and never even a hint of etch, grain, or edge.

These are expensive, powerful amplifiers, handcrafted in Switzerland and as attractive to listen to as they are to look at. If you can afford them, you should have a listen. If you own 458s, you'll be happy with the upgrade. At the very least, try the new cables!

darTZeel Audio SA High End Audio Manufacture
US distributor: Blue Light Audio
2725 SW Sherwood Drive
Portland, OR 97201
(503) 221-0465

Bob Loblaw's picture

Oh man are those ugly. The build quality looks incredible, but if there was an award for tackiest gaming PC, these would win it.

Graham Luke's picture

...you're the kind of guy who keeps a Ferrari in the garage, these things make perfect sense, n'est ce pas?

Bogolu Haranath's picture

Spectacle de richesse :-) ........

Long-time listener's picture

They need to stop letting engineers design the boxes...or whatever is producing visually unappealing equipment. Like the ATC P1 amplifier. Or the Cambridge Audio Edge amplifier--please don't put the knob right smack in the middle, and don't give me those broadly rounded edges. Or those wall-eyed Chord DACs. Just give me a clean, rectangular black box and I'll be very happy. And not that eye-piercing silver stuff either...

RH's picture

"They need to stop letting engineers design the boxes...or whatever is producing visually unappealing equipment."

Eye of the beholder.

I'm groovin' with the Iron Man look of those amps. Pretty cool.

JRT's picture

I like the aesthetic of "champagne" dyed anodized aluminum faceplate and rosewood panels. Sadly, the hardware that I want is not dressed like that, and form follows function in the priorities.

wilco's picture

in Audio are all over the map: from boring to ridiculous to just plain ugly.

I actually think the Darts are beautiful.. Maybe bordering on ostentatious, but they do "look" like $175K amps!

The most prominent high end speaker design that I could not stomach be in the company of-- no matter how heavenly they may sound-- are the Wilson Speakers. Robotic, clunky, aggressive-- clearly the work of a design-impaired engineer.

Long-time listener's picture

Butt-ugly. Once, years ago, I heard a pair of them in a showroom. I didn't think they sounded good either.

Michael Fremer's picture

SOUND GREAT. Come over and listen

Michael Fremer's picture

must be single

Michael Fremer's picture

I obviously disagree

Bogolu Haranath's picture

Conclusion (or, summing up) ..... MF is gonna upgrade and buy the new darTZeel NHB-468 mono-blocks :-) .......

Bogolu Haranath's picture

'cause ..... there is more there, there :-) ........

tonykaz's picture

just kinda shows that his $1,000,000 system wasn't all that dam good in the first place.

Who will pay for it? we subscribers or the Manufacturer needing some Publicity? and other manufacturers.

We at General Motors regularly supply our "Advocate" Reviewers with Long Term Loaner Cars for their families, we consider the practice pervasive, we would even "help" them write their reviews.

Tony in Venice

Ortofan's picture

... a Toyota made in the previous century instead of a new GM car.

tonykaz's picture

Thanks for the referral, I just had a quick look at one of his "explanations" and was delighted.

His Garage is "FILLED" with hoarding Junk so he must have important opinions on things.

I Subscribed Immediately! ! Scotty will be one of my 121 YouTube Subscriptions of interesting people with things to say and the natural ability to say them. He's Loquacious


You're right, GM would NEVahhhhhh let this guy near any of our New Cars or old ones if we could help it. We have a rather rich field of serious quality gaps that need forgetting.

Since we are talking about GM's embarrassing....


Tony in Venice

Michael Fremer's picture

very good

JRT's picture

(edited toward something more suitable for comparison)

Like a pair of Wavac SH-833 power amplifiers, these seem to be more focused on ostentatious conspicuous consumption rather than high performance. I would expect to find better performance at very much lower price point.

Wavac SH-833 subjective review and measured performance (MF seemed to like these too):


Performance: I want amplifiers that provide adequately clean and load invariant gain, with output capability that is well suited to the application, and with balanced inputs and internal grounding schema compliant with AES48.

Bogolu Haranath's picture

That Wavac SH-833 has about 4 bits of resolution and costs $350,000 ....... This darTZeel-468 has about 11 bits resolution and costs $170,000, which is less than half the price of that Wavac amp ....... So, the darTZeel amp is a better deal :-) ..........

supamark's picture

I have one (a power supply cap finally failed about 2 years ago, haven't had it fixed/recapped yet). Just one would be needed (it's power output was VERY conservatively rated - think Pass XA25 conservative). It would certainly win in 1 area - power output, and probably win in bass control (almost certain - it's the thing the amp does best, and does it exceptionally well). might beat it on macro-dynamics due to greater output power. would otherwise likely get its clock cleaned.

jtshaw's picture

Mr. Fremer does a fine job of describing the sound of this amplifier. And I was thinking, why not just buy a pair of Wharfedale Dentons or Lintons, which to my ears are voiced to sound pretty much the same at comparatively miniscule money? I have a pair of Dentons attached to an AVM CS 2.2 all-in-one unit in a bedroom system, and the sound is so good I never feel deprived.

chuckles304's picture

Never could understand the name "darTZeel".....only now, upon learning the founder's name, do I see that it is simply a re-ordering of the name "Deletraz"....


Bogolu Haranath's picture

They have all the 'Zeal' of Delétraz :-) ..........

drblank's picture

Then you should have a room like this.

https://www acousticfields com/state-of-the-art-acoustics/

ChrisS's picture

You don't recognize the color scheme?

Bogolu Haranath's picture

Yes ..... Great observation ........ Those are Iron Man colors :-) ........

Bogolu Haranath's picture

Crimson & Gold :-) ...........

ChrisS's picture

...Stark's "arc reactor" on the side.

ChrisS's picture

All you need is a "Tony Stark/MCU" signature...

tonykaz's picture

After all, Wilson $750,000 Loudspeakers have been featured in this Magazine.

What the hell are the Top 1% supposed to buy? , NAD you say ???

Of course, having pricy eye-candy on the Cover will sell Magazines at Book Stores. ( won't it ? ) Do these things look like something from Toys-R-us?

But still, can we expect any sort of relevance to Mainstream Stereophile Readership??

This Manufacturer murmurs about the quality of the Reviewer's Mains Voltage, I wonder why the Reviewer doesn't even have a PS Audio P20 Power Plant to insure adequate Mains Supply if trying to accurately evaluate the World's finest Amplification System. Or, why didn't the Manufacturer take steps to insure Review integrity ? ( Price no Object Reviews call for going all the way ).

Most of us will never meet anyone that "could" own this type of gear, insomuch as we are on the poor side of the Velvet Rope.

It's said to be a beautiful review. I might suggest that the Amps are as strikingly or purposely grotesque at those $750,000 Wilsons that Mr.JVS had his daringly embarassing picture taken from behind.

Maybe if I owned a Gold Toilet and a $5,000 Shower Curtain I could ....

Ok, lets make our Choice: these Amps or a Loaded Tesla S with about $60,000 Cash in the Glove Box for Impulsive Purchasing , can we have a Show of Hands?

Tony in Venice

ps. Dam good Journalism shows us how outrageous things can get.

JRT's picture

I have zero desire to own anything Tesla, and have more disdain for Tesla products than Bose products.



Invasion of privacy:


Monitoring and data logging is so excessive that some Teslas are now bricking due to flash memory chips are failing from too many write cycles.


tonykaz's picture

Well, Okey, No Tesla for you

or me, I'll be riding 500 miles per month on a Cargo rigged Bicycle for the rest of my Life.

Tony in Venice

Bogolu Haranath's picture

FYI ....... Bose Model 700, Bluetooth, noise cancelling headphones ($400), were one of the 'Top-Picks' by the Sound & Vision magazine, recently :-) ........

Robin Landseadel's picture

"Of course, having pricy eye-candy on the Cover will sell Magazines at Book Stores. ( won't it ? )"

Not if people don't go to Bookstores in this age of Amazon/Kindle or aforementioned bookstores decided that said magazines weren't moving. About 15 years ago I worked at a "Borders", we had all the usual audio subjects on the Magazine racks, had to strip the covers to send back to the publishers and toss the 'zines into the dumpster most of the time. About a year ago, went to my local Barnes & Noble, they had only two "audio" titles on the racks. Used to find audio magazines in the magazine racks of supermarkets, those have been replaced with Gun magazines. I'll bet most folks reading Stereophile never encounter it in a Bookstore.

There's gonna be, say, a couple hundred people in this world who would even consider buying this ultra-pricy stuff. So I suspect it's really more about the magazine's writers getting their jollies at this point than anything else.

tonykaz's picture

Schiit just released Three Important NEW Products.

Audiophile Candy for Everyman.

1.) Made in USA ,

2.) Uncompromising Good product and performance,

3.) built by a group of loyal employees,

4.) sold at fair prices.

5.) Substantial Warrantee of 5 years.

6.) Company with a History of Integrity

7.) Schiit gear retains 80% Value for eBay re-selling.

Audiophile Readership have never been taken care of like today.

Tony in Venice

ps. I've owned a range of Schiit products but I'm not "rewarded" in any way by Mr.Stoddard or the Sr. Mike.

ps. Stereophile Staff were the ones that introduced me to Schiit back in 2011.

Ortofan's picture

... Schiit Sol turntables, yet?

tonykaz's picture

I'm not Turntable since I stopped Selling & Servicing every Brand of TurnTable Made, in 1985ish. Esoteric Audio had a compete Turntable Lab. with Tektronix Scope and critical Mechanical instrumentation for precision Set ups. We even did Cantiliver compliance measurements, suspension evaluations and Arm Mass matching. We were and are Scientists from General Motors Research Laboratory.

I embraced digital when Tyll & Steve G introduced me to Schiit & Sennheiser at RMAF2011.

I still own a considerable collection of Vinyl that I'll eBay at some point in the future.

My Psychiatrist and I have both had our Synapses rewired for the Great Digital Sound Quality. ( just like the Pro Audio people have done 100% )

Now, a presentable Vinyl System seems to electrify the Either in the Listening Room. That is it's magical power but I'm like Jabba the Hut, it doesn't work on me, I still see it's many flaws.

Tony in Venice

Bogolu Haranath's picture

Seems like Mr.Tony got tired of all the 'Stitching' and 'Non-Fill' on the vinyl records ....... (see AnalogPlanet) :-) ........

Faulty-thesaurus's picture

Michael claims that the mere existence of a (relatively) small number of wealthy people who purchase absurdly expensive audio equipment is a convincing reason to review this product. I’m not swayed by that argument.

supamark's picture

If you consider the market for this sort of thing as the "the 0.1%" in wealthy parts of the world (US, Canada, The EU, Australia, parts of Asia, etc) that's conservatively about 1 billion in population total. 0.1% of that (1 billion * 0.001) is about 1 million people. cut out 90% as not interested in audio/part of same household/whatever and that's still about 100,000 people who can easily afford this and might be in the market. Who do you think buys all that silly expenisve Nordost cable (who advertise quite widely in the audio press)? same folks (I know I ain't spending 10x my system price for speaker wire lol). I assume Nordost would not continue to widely advertise if it wasn't bringing results.

Add to that number those who like to read about crazy expensive gear and you've got a big chunk of this magazine's audience.

Plus, it's an interesting and unusual circuit design which carries its own appeal.

jeffhenning's picture


Not because of it's aesthetics... Personally, not a fan, but just fine if you are.

Ridiculous because this over-priced Lego-blocked POS can't outperform the best amps in the world that cost from $3K to $6K each.

darTZeel should be ashamed, but, hey, I guess there are consumers that truly don't care about ultimate sound quality at these prices. Wilson Audio proves that.

This amp is a bad joke.

To it's owners, "Even though your heart is breaking, laugh, clown, laugh!" (Think of the great Daffy Duck version)

Ortofan's picture

... (with the exception of KR, who uses Benchmark amps) seem to have an expressed preference for overpriced and under-performing amps?

(Wait for this month's "Listening" column from AD.)

billyb's picture

Still waiting to see measurements on Art Dudley's reference Shindo amps.

IMHO, if Stereophile is going to recommend multiple components from a single manufacturer in class "A", regardless if it was recommended in a column, review, or Fremer's youtube channel -- They should measure the damn amp. Give me a break.

**Crickets from JA**

ok's picture

At the time of the original NHB-458’s release I remember Deletraz stating that he was perfectly happy with the sound of his NHB-108 stereo amplifier though constantly pressed by some well-heeled, mostly Asian, customers to make for them something ..bigger. So let’s not blame the man for trying to keep his customers satisfied. I'm not even sure that hi-end audio customers nowadays are virtually outnumbered by the almost extinct but still noisy mid-fi ones –certainly not profitwise or else manufacturers would have never turned their backs to the latter in the first place. In the meantime ordinary people are mostly content with smart/phones or active solutions and for good reasons no doubt. By the way I have only heard the CTH-8550 integrated twice and save for some wooly bass it sounded truly magnificent.

dfh's picture

On the article's lead photo of the amp (angular view & front-face), the brass tag at lower center appears to end with "Michael Fremer" in script font (and has 4-lines engraving). In the front-face photo later in the article, the brass plate has the serial number (and 2-lines of engraving). Mr. Fremer's article states that externally the NHB-468 (review) and NHB-458 (Mr. Fremer's own amps) are very similar styling. Is the lead photo of Mr. Fremer's NHB-458, and the later photo actually the review NHB-468? Or as Mr. Fremer stated in the review, while he had no intention of purchasing the NHB-468's, was he seduced & gave-in to their enhanced performance! In any case an enjoyable read and thorough review (as always) by Mr. Fremer. Not only are my ears well trained, so are my eyes!

Jim Austin's picture

The photos with the ID plates are the ones Mikey tested, taken by a photographer we hired. The other photos are stock photos provided by the manufacturer. Many of the photos we publish are provided by manufacturers.

Those ID plates, by the way, were added by darTZeel before they sent them out, without our knowledge. I was concerned when I first saw the photos, since Stereophile reviewers should not agree to buy review samples before they've even been reviewed--so why was Mikey's name on them? And then I checked and found that the plate on the darTZeel stereo amp and preamp that I have in for review, from which I had never bothered to remove the blue tape covering the brass plate, have MY name on them. And I sure as heck haven't agreed to buy them and do not intend to do so: I mean no disrespect--they are very good--but I can't afford them, so they will go back when I'm done with the review. Maybe this is just something Hérvé does for a bit of fun with his review samples. Or maybe only with Stereophile. I haven't asked.

Jim Austin, Editor

A_Stone's picture

Strange claim on the part of Dartzeel manufacturer:

Dartzeel claims:
A (Current)-Source with voltage source characteristics.
That is contradiction in terms and therefore incorrect.

A current-source with voltage-source output characteristics is a VOLTAGE SOURCE.

Good review and set of measurements.
However, simulated-speaker loading would have been appreciated.

Trevor_Bartram's picture

As someone who has just suffered a second sudden hearing loss event (was it the head cold or flu shot at fault?) I'm still amused when Mikey waxes lyrical about expensive gear, must be the masochist in me. However, he's really shot himself in the foot this time, who will buy his $140K amp now the $180K amp reigns supreme? Perhaps, like us mortals, it will be confined to the bedroom/kitchen/office system, ha, ha.

David Harper's picture

which would include me I always suspect that the economies of scale will dictate that this kind of gear will, in reality,turn out to be technically unreliable and not particularly better performing, much like the venerable Delorian or the aformentioned Tesla. I recently bought a new honda civic(a two-door sport with a 6 speed stick) which has turned out to be the best handling and driving car I ever drove for less than 20K brand new. And I've owned or driven far more expensive "high performance" cars. Economy of scale is an awesome and underappreciated thing.

billyb's picture

Sounds like everyone ponied over to Fremer's house pretty fast the day you measured those amps. Were you aiming for surprise?


David Harper's picture

so this reviewer thinks a 170K amp sounds real good. Does it occur to this guy that his speakers are producing ten times more distortion(whether he thinks so or not) than this amp produces? And that this speaker distortion masks entirely any distortion produced by the amp? So if I order a 170K amp does it come with 169K in cash in the shipping box? Because that is the only way it could make sense. This kind of laughable stupidity is the reason anyone with an I.Q.over 90 finds high-end audiophiles to be idiots. Not to mention the moral obscenity of spending 170K on a stereo amp. Think about this:you could spend 5K and get a really good amp and have 165K left over to donate to fight the wildfires in australia or donate to Americas wounded warriors or to Shriners childrens hospital. Before I'm assaulted here by every audiophile let me confess; I have wasted a lot of money on audio gear.More than I care to admit.

ejlif's picture

you lame brains can't handle that some guys get to buy expensive stuff. I looked in the comments just for fun and how disturbing. I feel bad for these reviewers at Stereophile having to deal with such sour pusses

Michael Fremer's picture

You are so correct. At this point I just laugh at the pathetics

AmplificationDesignEngineer's picture

Dartzeel’s amp circuit design optimized using active, or perfectly resistive, load, which is in audio amplification world is a little bit too optimistic. Common speakers with 2-way or 3-way crossover have non monotonic Z(f) characteristic, where impedance mag could change from couple of ohms to 10..20 ohms easily. This amp specified damping factor (DF) is 25 (@8 ohm load), which is very low, comparing to competition. Low DF increases distortions for whole amp+speaker system, and limits speaker choises for the best sound experiense. Would be interesting to see measurement results for this amp using simulated loudspeaker load, similar to https://www.stereophile.com/content/dartzeel-nhb-108-model-one-power-amplifier-measurements.

Senecacato's picture

In this column, there are probably plenty of jealous, religious Americans who probably voted for a clown like Donald Trump although they should actually vote for the Communists. They find it hard to accept that many readers actually want to read about High-End products and that Michael Fremer has decades of experience and heard most of the products produced in stereo world. If just this product is beautiful or not is in the eye of the beholder. But I have no doubt that these darTZeel NHB-468 monoblock power amplifier are very good.