NHB-458 monoblock power amplifier

[A.wayne]

Semantics.. ?

You are word playing , Specs are the resultant factor , measurements are whats done to garner the specs, its academic and our discussion is regarding the measured specs listed by stereophile, you have to read back to see such .

 

[asiufy]

A. wayne,

You might think absolute top measurements are the way to go, as they'll eventually correlate to good sound. As the darTZeel manual very politely put, that's fine. But they (and I) politely disagree. As a matter of fact, in my view, it's just the opposite. Manufacturers obsessed with measurements will end up with gear that's not appealing to me.

What I'd like some of the "measurements are king" types to answer is why are the darTZeel amps routinely praised for their naturalness, clarity and transparency. If they're distortion -generating machines, why is that so? How could they be? The monster MBLs Fremer had at his place before have many times less distortion than the 458, yet the 458 was far more natural to his ears. Why is that so?


alexandre

 

[A.wayne]

Alexandre,

pretty dramatic post ..

No i don't think it's the end all or be all, read back thru my posts ....its a sliding scale ...... all amplifiers are distortion generating machines, mine , yours, all, its why we measure... opps sorry, some may call it color, fluidity, warmth, sonic characteristic....

My apologies ...

My comment on the DZ is that it has an undersized PSU and it shows below 4 ohms, its not opinion , that's fact , verified by the stereophile bench test. Not the end of the world , just reality if you have a 2 ohm speaker, Nothing to do with its subjective sonics, which you may or may not prefer.



Regards,

 

[mep]

Semantics.. ?

You are word playing , Specs are the resultant factor , measurements are whats done to garner the specs, its academic and our discussion was regarding the measured specs listed by stereophile, you have to read back to see such .

No, it's not semantics at all and I'm not word playing. I'm a realist who accepts things as they are and not what I wish they were. If specs were the results of measurements, then the specs would always agree with the measurements that were taken by competent outside parties with proper calibrated test gear. It's simply not the case and it's not academic as you say. If condescension was currency, you would be a very rich man.

 

[A.wayne]

OK, so you're rich ......... congratulations !!!

 

[FrantzM]

Originally Posted by wizard
From Sterophile and Hifi News measurements of 458.

Continuous power output with 1% distortion in 8/4/2/1 ohms.
530/900/1025/276 watts.

Distortion at 0,5% - now the power supply begins to struggle in 2 ohms.
500/850/750 watts.

Distortion at 0,2% - big problem in 2 ohm.
450/750/100 watts.

Hi

The conclusions from these masurements are suspect. It is clear that the amp is not comfortable with 1 ohms impedance yet it drives them albeit albeit 3 dB down from the output at 8 ohms which is fair .. some amps protective circuitry would have acted up in such low impedance .. This is stated as "continuous" so it can drive such load all day long if needs be

Now let's look at the quotes for distortion, likely taken from a graph. 0.5 % is insignificant and the last figure simply means that distortion rises at 2 ohms not that the amp cannot deliver the power .. the amp still delivers 1000 watts at 2 ohms albeit with some higher THD so??? ... To suggest that the PSU is "struggling" is a reach ... The amplifier seems from these measurements capable of driving 2 ohms at 1000 watts continuously .. Very good numbers if you ask me and and quite capable of driving some real low impedance out there ... and these don't still tell me how it sounds ... A thud .. Come on! I know we, audiophiles are fond of hyperbole but ...

 

[mep]

Frantz-Stand by for a bucket-full of condescension dressed up as superior knowledge.

 

[microstrip]

And in another thread, microstrip said this same amp was the best he heard with the monstruous Aidas. (...)
alexandre

I must add that I never listened to the ARC REF 750 with the Aidas's ...

Although I am very critical about these shoot-outs of power amplifiers, there is one I would love to participate : a Dartzeel NHB 458 versus 3 Dartzeel NHB108 driven by a Dartzeel NH18NS using the 3 special 50 ohm outputs that have intrinsic filtering to reduce intermodulation in multi-amp systems. The speaker would be the Aida, that can be tri-amplified.

Yes, I know curiosity killed the cat ...

 

[Roysen]

I would like to add my 2 cents. I have heard the 458 driving the Q5 in two different systems and in two different rooms. Both rooms were quite big. The bass certainly was not loose to these ears. Several amplifiers measuring better than the 458 have in my opinion had bigger problems with the Q5 than the 458. So measurements should like JA has written in Stereophile only be used as guidelines. Final judgement must be done by ear.

Thanks,
Roysen

 

[A.wayne]

Frantz-Stand by for a bucket-full of condescension dressed up as superior knowledge.

That is the most naïve statement I have ever read. .

If condescension was currency, you would be a very rich man.

As opposed to Dressed up Irony ....try discussing the topic ...

 

[asiufy]

I must add that I never listened to the ARC REF 750 with the Aidas's ...

Although I am very critical about these shoot-outs of power amplifiers, there is one I would love to participate : a Dartzeel NHB 458 versus 3 Dartzeel NHB108 driven by a Dartzeel NH18NS using the 3 special 50 ohm outputs that have intrinsic filtering to reduce intermodulation in multi-amp systems. The speaker would be the Aida, that can be tri-amplified.

Yes, I know curiosity killed the cat ...

OR you could do a pair of 458s for the midbass and a pair of 108 for the highs

 

[Mike Lavigne]

I must add that I never listened to the ARC REF 750 with the Aidas's ...

Although I am very critical about these shoot-outs of power amplifiers, there is one I would love to participate : a Dartzeel NHB 458 versus 3 Dartzeel NHB108 driven by a Dartzeel NH18NS using the 3 special 50 ohm outputs that have intrinsic filtering to reduce intermodulation in multi-amp systems. The speaker would be the Aida, that can be tri-amplified.

Yes, I know curiosity killed the cat ...

when i had the NHB 458's in my system for a month 2 years ago your thought did cross my mind......and i have an idea of how that would go. the 458's would sound better by a good margin.

prior to owning the MM3's i had VR9SE's, and i did have a pair of NHB-108's vertically bi-amped, plus the VR9SE had powered subs. i did not run the NHB-18NS with the separate BNC's for mid's and highs with that bi-amped set-up, but there is still a difference in the life-like energy percieved on the 458's compared even to a pair of 108's on the mids and highs.

to complicate my conclusion; there has been a circuit upgrade to the 108's since that time i had the pair on the VR9SE's so who knows whether that would tip things more in favor of a triple stack of 108's, but i don't think so. the 458's simply do things which are not simply gross power related. it's like the music is supercharged in some way and you hear far into the music. there is a 'completness' to everything.

i hope someone does try your idea at some point as one could assemble a triple stack of 108's at a relatively reasonable investment. my MM3's and MM7's unfortunately are not 'bi' or 'tri' ampable......at 93db and 96db efficient they have little reason to be.

 

[asiufy]

I think this experiment would be valid for people who already own good ($$$) speakers in the 86-88dB efficiency range, and would like to try out darTZeel. There's a huge gap between the 108 and 458s, price-wise. Even though we all know something in between is coming, in the meantime, perhaps darTZeel could work on a setup with 18NS + 2 108s. That would end up being still cheaper than the 458, and cheaper than some of the competition still...

Perhaps some of the darTZeel dealers could work on that!

alexandre

 

[A.wayne]

when i had the NHB 458's in my system for a month 2 years ago your thought did cross my mind......and i have an idea of how that would go. the 458's would sound better by a good margin.

prior to owning the MM3's i had VR9SE's, and i did have a pair of NHB-108's vertically bi-amped, plus the VR9SE had powered subs. i did not run the NHB-18NS with the separate BNC's for mid's and highs with that bi-amped set-up, but there is still a difference in the life-like energy percieved on the 458's compared even to a pair of 108's on the mids and highs.

to complicate my conclusion; there has been a circuit upgrade to the 108's since that time i had the pair on the VR9SE's so who knows whether that would tip things more in favor of a triple stack of 108's, but i don't think so. the 458's simply do things which are not simply gross power related. it's like the music is supercharged in some way and you hear far into the music. there is a 'completness' to everything.

i hope someone does try your idea at some point as one could assemble a triple stack of 108's at a relatively reasonable investment. my MM3's and MM7's unfortunately are not 'bi' or 'tri' ampable......at 93db and 96db efficient they have little reason to be.

Mike is there any measured data on the MM3 AND 7's , i was not able to find any, particularly the impedance magnitude and phase ...


Regards,

 

[Gregadd]

So let's get this striaght-

Beyond a certain threshold of measurements improvements are irrelavent.
Let that sink in for a moment.
Now, your amp is no good becuase it fails to exceed that threshold?
Ok?
greg.

 

[A.wayne]

Huh...?

 

[Mike Lavigne]

Mike is there any measured data on the MM3 AND 7's , i was not able to find any, particularly the impedance magnitude and phase ...


Regards,

other than what is listed on the spec page of Evolution Acoustics here....

http://evolutionacoustics.com/evolution-acoustics2/specifications-for-group-brochure-4.pdf

....i don't have any additional detailed specifications. note that the MM7's consist of 2 separate towers.

what i know is that the MM7 uses a first order crossover, and it is time aligned and phase aligned. i'm at work and that is from my memory, and i'm no spec expert....i listen.

 

[A.wayne]

Thanks Mike .....are you getting all 4 towers ...?

 

[mep]

Thanks Mike .....are you getting all 4 towers ...?

Seriously?

 

[Mike Lavigne]

Thanks Mike .....are you getting all 4 towers ...?

yes. i'm getting 2 full towers. i cannot imagine buying this speaker without the bass tower....although i will have the main towers 'only' for 2 weeks while the bass towers are being built and shipped. this speaker system comes in 14 large wooden crates, 6 for the main towers, and 8 for the bass towers. where they are assembled there is not space for all 14 crates at once, so they are shipped in 2 waves.

there has been one MM7 buyer so far that did only get 1/2 bass towers. he wanted less height due to a view out windows.

essentially each bass tower is 2 separate systems which can be independantly adjusted and each has it's own amplifier. it uses 2 separate power cords. so 1/2 is still 2 15" subwoofers in sealed boxes with a 1000 watt amplifier.