Review of Dartzeel NHB-108 Amplifier


Dartzeel is a relatively new entry to the high-end game. Despite being reviewed by John Marks in a recent issue of Stereophile, the company's only current product offering, the NHB-108 stereo amplifier, hasn't gotten a lot of press on these shores. Hopefully this "review" will do its part in rectifying that.
As many of you probably already know, Switzerland-based Dartzeel is the brainchild of one Herve Deletraz. Herve is a wonderful guy who's dedicated to the very best customer service. As essentially a one-man operation, I'm sure his time is limited, but he's always responded to my e-mails in an extremely courteous, timely manner.

On to the amp. I'm not one for technical details, so I'll leave them to those of you who want to visit Dartzeel's website. Basically, the 108 is a "purist" stereo amp rated at a relatively modest 100 wpc. Its smallish dimensions belie its weight, which measures around 65-70 pounds.

Internally, the amp is incredibly well laid out (if tightly packed), with an attention to detail that one should expect--but doesn't always receive--from components in this price range.

Outside, it's purely love-hate. (Refer to the website for pictures). Either you get it or you don't. Personally, I've grown used to its appearance over time, but it's taken a while to become acclimated. If WAF factor is any sort of issue, practice up on your compliments. Then again, I may be overstating the case. While it's not Liv Tyler, it's not Janet Reno, either. Time reveals its inner beauty.

Performance-wise it's a much more straightforward issue. In my experience the 108 is the most balanced, natural-sounding amp I've ever heard. It has a way with timbre that's downright spooky--up there with the very best tube units one cares to mention. The sound is just "right"--every note is reproduced with a tonal correctness and warmth that is as close to the real thing as I've heard in an amp. Because of it's sheer naturalness, it can take a while to overcome the initial impression that it is somehow soft or rolled off. That is most emphatically not the case! Dynamics are crisp and fast, and the frequency extremes are right where they need to be--not overstated or highlighted at all, just perfectly natural and realistic.

The only potential weakness of the 108 is its power rating. It flows a nice amount of juice for 100 watts, but one could theoretically run into problems with particuarly current-hungry or inefficient speakers. Part of the amp's midrange purity, I believe, is attributable to the use of the bare minimum of bipolars in the output stage. That, of course, comes at the price of power, but in this case the tradeoff is more than worth it. Just take some care in speaker matching--as you should, anyway--and you'll be rewarded with a sound that balances the very best of solid state with a midrange that will make some question whether they even need to fuss with tubes.

Despite its novel physical appearance, the need for careful speaker matching, and the fact that the US dollar has been taking a Tyson-like beating lately, the Dartzeel is a serious contender in the super-amp category. Yes, there are amps out there that do this or that "better" than the 108, but I've yet to hear one that strikes a better balance between the various areas of performance. It's a stunning piece of engineering and a landmark amplifier.

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Product Weakness: Appearance is strictly take-it-or-leave-it. Power rating requires some attention to speaker load. Cost.
Product Strengths: Naturalness, midrange magic of the highest order, speed, dynamics

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Associated Equipment for this Review:
Amplifier: Dartzeel NHB-108
Preamplifier (or None if Integrated): EMM Labs DCC2
Sources (CDP/Turntable): EMM Labs CDSD
Speakers: Von Schweikert VR-4 Jr.
Cables/Interconnects: Jena Labs Pathfinder
Music Used (Genre/Selections): Rock, blues, country, some classical
Room Size (LxWxH): 24 x 20 x 7
Room Comments/Treatments: Echo Buster, ASC
Time Period/Length of Audition: 3 months
Other (Power Conditioner etc.): Shunyata Hydra-8
Type of Audition/Review: Product Owner
hooper

Showing 14 responses by mikelavigne

i must disagree with my friend Hooper (and particularly Cinematic Systems). i currently have the Kharma Midi Exquisites in my room and am listening with a single DarTZeel NHB-108. my room is pretty large (21' x 29' x 11') and at first i did feel that the Dart did not have quite enough 'grunt' to really rock in my room......but as it has broken in it has continued to get it's legs, open up, and gain grip. in the last week the bass dynamics have really kicked in and there doesn't seem to be any lack of dynamics.

my context of dynamic amps include a few heavyweights, Levinson #33, Halcro DM58 and numerous others.

the Midi Exqusites don't plumb the depths of deep bass below 30hz in my room (but that is a speaker/room issue).....but there is no straining or any dynamic limitations i can perceive.......i have pushed this combo pretty hard but have yet to hear any hardness or clipping.

the Dart seems to be an excellent real world amp and is plenty of amp for the Midi Exquisites.
sir speedy; i heard all the speakers you mention at CES and in other places......as well as the Midi Exqusite's at CES.

first, i was NOT impressed by the Midi's at CES......and if you based your opinion of the Midi based on CES i would understand your comment. the same for the VR9.....there were times when it did not sound satisfying (other times magnificent).

i have now had the Midi's in my room for the last 2 months......and what i hear is on a higher level than those other speakers in terms of refinement, coherence, and simply getting out of the way of the music.

none of those speakers 'smoke' the Midi's to my ears......although if you focus on particular aspects of the sound you can make any case you want.

the Kharma's aren't cheap.....but this level of precision never is.
i've gone back and forth whether to respond to 'Cinematic Systems' regarding his interpretation of mine and other posts as some sort of dismissal of Kharma in favor of Von Schweikert. i guess some response is in order.

first, no one has had a chance to directly compare the better Kharmas with the new VR9SE as of yet. until that happens any actual comparitive opinions are just that.....opinions. does the VR9 equal Kharma's coherence, Kharma's ability to disappear, Kharma's mid-range clarity? those are questions.....of which answers can only be guessed at.....some can even make educated guesses.....and some have.

i have loved Kharma's for the last 4 years and i still love them. they have a certain magic and will continue to have it. like any speaker, there are some design trade-offs. the Kharma doesn't plumb the depths of deepest bass, the Kharma is not the most macro-dynamic speaker. the Kharma is all about getting out of the way of the event......and having a great balance.

the VR9 may just equal the Kharma at the Kharma's strengths......if so it actually may be that 'speaker without compromise'.......since it definitely has the dynamics and deep bass thing down pat.

any Kharma owners should be secure and confident in their speakers. nothing has changed. we just have a few poster's that like to over-simplify things......if a Kharma owner (me) choses another speaker due to dramatically different room challenges......all of a sudden Kharma has slipped a notch......that's a bunch of bull.

the reason we have lots of Kharma owners is due to the very special performance of those speakers. this special performance has never been about the best anything. it has been about being real. when anyone tries to break down the Kharma into pieces he completely misses the whole point of the speaker.

people change speakers and amps for a host of reasons. sometimes it is that the SOTA has moved on, sometimes it is a desire for more bass or dynamics, sometimes it is a desire for a more intimate and non-hifi sound. i have changed for all those reasons at one time or another. there is even changing due to non-perfomance reasons.

as far as amps, while i think the world of the DarTZeel the Tenor is still on the same level to me......different but equal. both amps have their strengths.....and both likely have their ideal speaker match.

sorry for the rambling......but this whole 'better and worse' thing is just wrong.
Sirspeedy; if you look at the price issue of any Euro product......it has taken a hit in the last few years......the Kharma's more than some. i am not going to judge the current importer.....he can either make the case for value or not. i would only say that Kharma's still do most things better that are important to me than most competing speakers at ANY price point. Charles von Oostrom is an artist at designing speakers and IF you love what he does then you may want his speakers. i would also say that Kharma's have as much refinement in their speakers from the bottom to the top of their price range as any other.

i would agree that Kharma is not the best bang for your buck speaker......if that is most important.

i currently do not own Kharmas.....the Midi's are loaners while my Von Schweikert's are being built. details of my speaker journey are on my system thread if you are interested. my Kharma Exquisite 1D's, the Midi Exquisite's, and the VR9's are three different speakers which are all easily justifiable in my mind.......and i could live with and love any of them.

as you can see; i have no ulterior motive to promote Kharma. i just happen to really enjoy them and their way of playing music. but they are not the answer to everyone's taste, or everyone's priorities, or all rooms.

my previous smaller room would have been 'overwhelmed' by the VR9's......my Exquisite's were quite good there. if i had stayed with a medium sized room i would have never even thought of changing speakers.

i do expect that the VR9 will ultimately get me closer to my musical nirvana than any other speaker that i have heard could......but that is a story for a future day when it is in my room, broken in, and properly set up.

i reserve the right to come to whatever conclusion that presents itself at that time.
sirspeedy, as Howie mentioned.....i am not one to change gear willy-nilly. i had owned to Exquisite's for almost 4 years.....and had no particular desire to change until the new room came along and gave me a reason. i've had the same cables for 4 years, the same passive pre for 3 years, and other aspects of my system are pretty stable too. the reason for building the room is that i realized the limitation of gear......after i had tweaked and tweaked over a few years to wring all i could from my gear and previous room.

we agree on the 'art' aspect of the Kharma.....yet.....it's simply not the issue. aesthetics are obviously important to me; but not at the expense of performance. a few years back i switched from the Linn CD-12 to the emmlabs......from beauty to the beast.....but the beast was better. and over the last three years my decision to switch to the emmlabs has proven correct FOR ME. there have only been 4 sets of VR9's made so far and there is limited exposure of the product.....i am not looking to make a popular decision......i want the right product for my situation.

i do have one question; where do you come up with my 'Rock Music Tastes'? my personal viewpoint is about exactly opposite and has been stated numerous times. i would never want what i refer to as 'one-note bass' or 'rock-show bass'. i would take the bass performance of the Exqusisite's in my current room 1000 times before i would want boomy bass energy for the sake of itself. bass performance needs to serve the music.....and never be an end to itself or prominent. my perception of the VR9 is consistent with that viewpoint and if that proves to be untrue when i have them in my room i will go another direction. in fact, the main reason i did not go for a separate subwoofer with the Exquisites was my fear of incoherence and boomyness in the bass.

i asked my designer to design the best room he could; and not the best room for the Exquisites. i knew the Exquisites did not have the deepest bass extention and the most visceral dynamic performance......i didn't know how they would actually work but i wasn't surprised by what happened.

Cinematic Systems; i must disagree with your opinion that different amps might make huge differences in my bass extention. the truth is that the anachoic bass performance of the Exquisites is not too different than what i get in my room. the rear port just can't do enough in my room to support the 40hz to high 20hz range that it will do in most rooms. this is a speaker/room issue, not an SPL issue. it was down over 15 db from 20hz to almost 40hz.....so another amp is NOT the issue. another amp may add a sense of weight or presence, but it won't measure differently......and would come with unacceptable trade-offs. it is POSSIBLE that i am wrong here......but not too likely.

i have had many amps in my previous room (maybe 20 SOTA amps) and i never had one that seemed to significantly effect bass EXTENTION. they might allow better control, better articulation, or a sense of foundation......but they won't make 40hz extention.....22hz extention.

the Tenor 300 monos have lots of bass control and were equal to many high powered amps when i had them in my previous room. these were the amps my new room was measured with.
thanks sirspeedy for the good wishes. the attention (good and bad) my postings attract is of my own doing. if i don't want the feedback i should just keep to myself. mostly i enjoy the discussions and relationships that result from my choice to share my experiences. many directions i have eventually gone have resulted from advice i initially rejected......i try to stay open-minded to any possibilities.

since this is all just fun for me anyway.....i typically don't get too riled over any comments.....i leave that sentiment for business.

best wishes to you too.
Cinematic Systems, you are confusing my Exquisite Ref 1D's with the Midi Exquisites. i have only throughly measured the big Exquisite Ref 1D's in my new room. these are now sold and i am using a loaner set of Midi Exquisites.

i am 'guessing' on my anachoic comment......but it makes sense that if the 1D's only went to 40hz in the new room that this would closely resemble what they would be anachoically.

in my old room the 1D's were flat to about 30hz and 3db down at about 28hz. you could barely hear them at 25hz. that room pressurized very easily and the 1D's had a real grip. if i plugged the rear ports they only went to around 38-40hz in that room.

one of the previous Kharma importers that is very familiar with the all the versions of the Exquisite Reference told me that they only went down into the 40hz region in any large room.

so my conclusions based on all the evidence is that this is a speaker/room size issue and not a problem with my room or with the speaker per se.......just that speaker in that room.

regarding the Midi Exquisite's that i now have......i have only done a rudimentary measurement with the Rives Test CD2 and my Rat Shack meter (using the test tones equalized for the Rat Shack meter). the Midi seems to be flat to 40hz, down slighly at 31.5hz, and down about 7db at 25hz.

when you compare the Midi's rating by Kharma as down to 22hz and the 1D's rating as down to 25hz this doesn't compute. my conclusion is that the 1D only truely goes to around 30hz in a typical room......which seems consistent with my observations and comments of the previous importer.

all this is not to disparage the 1D, which is a fantastic speaker and wonderful.....but i'm not going to worry about my room......it was the speaker.

another interesting thing was the 'hole' or 'suckout' (-5db at 80hz) that i mentioned in my room article is non-exisitant with the Midi. the Midi is flat at 80hz.
French Fries.

no

#1. yes, maybe
#2. yes
#3. unfortunately, yes
#4. no, not necessarily
#5. probably, what's a DK?

have a nice day.
Hooper; i wanna know how you planned all this last summer......

it's always the quiet ones you gotta watch.
Sadeek; my plan is to compare the DarTZeel and Tenor 300 Hybrid Monos on the VR9's. i do have experience with the Tenor 75 watt OTL's and have heard the ML2's numerous times at shows. the VR9's would be just fine with either the Tenor OTL's or the ML2's......a matter of taste.

yes, the Tenor 300 watt monos are the real deal.....the best all-around amp i have yet heard (the DarTZeel may be better but too soon to say for sure).

the ML2's (or ML2.1's) are very nice but have never really 'engaged me' onto the music.....as both Tenor amps and the DarTZeel have.

maybe someday i'll get the chance to spend some quality time with the ML2's in my system and have a better feel for their magic. the VR9's would seem an ideal speaker for the ML2......then again the VR9's are likely ideal for about any amp with their efficiency and no need to provide deep bass drive.
Sean; i've kinda got frustrated with this thread. i even sent Mr. Audiogon a post complaining (for the first time ever) about 'delays pending moderator approval'. if the 'gon' wants to slow down a thread, that is their business......but then i just lose interest. i never 'stir the s**t' and resent being treated as if i do. i suppose it is easier to simply filter threads instead of individual 'goners'.......but i don't like it.

end of rant.

yes, Rives Audio did 'do the math' on speaker and listeneing position placement......which turned up 2 'best spots' for my listening position and one ideal speaker position. i am sitting within 4 inches of the more near-field of the two listening positions. the speakers are about 6 inches closer together and 4 inches forward of the original suggestion.

i don't know exactly how Richard Bird did the math, but you could ask him.

i moved the speakers all over the place and the bass performance was essentially the same......so i ended up just focusing on the soundstage. since the speakers are so far away from room boundaries wherever i put them; there were no changes in the tonal balance as i moved them around. what is almost spooky is how balanced the room sounds as you move around......the soundstage resembles how live music sounds as you would move around a nightclub.

it will be interesting to see how the VR9's will do.

i'm no speaker designer and don't pretend to be. i'm not sure about just how extensive your experience is with the VR9......but your conjecture about how many if it's design choices MIGHT affect performance seems a little too 'all-knowing' in it's tone without some extensive personal auditioning.

after spending hours speaking to Kevin Malgrem, the primary designer of the VR9 and VR11, about how choices were made in it's design......my OPINION is that your theories may not be correct.....but i admit to not being an expert......although i do have a fair amount of high performance speaker listening experience.

i did spend 10 to 12 hours listening to the VR9 at CES. my perceptions are not consistent with your theories. you are guessing about how the crossover is actually designed and exactly how parts are used. you are guessing about how low the front mounted woofers go. many speakers use a rear mounted port for deep bass support (Kharma)......and yet there is no backwave discontinuity percieved......why would a rear mounted subwoofer be any different (unless you listened and identified the cause and effect)......or had experience with that issue on other speakers.

many designers don't disclose exactly what they are doing (Wilson, Kharma)......you gotta listen to judge.

you could be absolutely right.....or absolutely wrong......but only listening will tell that.
Sean; my comments about Audiogon's moderation policey were not in any way directed at you (i was simply whineing); we have never had any acrimoney of any kind between us and there is none now. we do disagree on whether you have adaquate information to take such strong stands on the design of the VR9's......but that's in no way personal. i respect your obvious knowledge and many contributions to the community.
hi Keith, after hearing both the Midi Exquisite and the CRM 3.2 at CES with the Kharma sub.......i decided not to go the subwoofer direction. i never did try a sub in my room with my old Exqusites......i did seriously consider it however.

"That dart isn't near worth the money they are asking".....if that is true, then neither is the Lamm ML2.1 or ANY other amp i have heard. i might agree that no amp is WORTH $18k....but if ANY are then IMHO the Dart is....but that is only my opinion based on my listening for the last few months.

YMMV
DBK, the DarTZeel is quite wonderful in my fairly large room on the 90db, 4 ohm nominal Midi Exquisite. i would guess that in a more normal sized room that the Dart would be just fine on the 94db, 6 ohm nominal VR7.

any amp/speaker combo needs to be auditioned to be sure of compatibility.....but based on my experience with the DarT that could be a wonderful match. possibly other amps might offer more of some things but the refinement of the Dart is very special and is approached in my experience only by some tube amps.