Hifinews review D'Agostino Momentum amp

[FrantzM]

Heard Both!! That was the episode in which Boz Scaggs got into the room! I remember being simply shocked ... Very rarely do system fools in such a startling fashion ...
For those who haven't heard them yet .. The Lamm 2 have little of the SET signature .. yet retains the seduction in the midrange . .It is not only seductive but utterly realistic ..
On the subject at hand , that of the Momentum amplifers. I am pleased the hum and buzzes were addressed and that is what criticisms are for IMO. Correcting flaws and making a product better.

On the subject of reliability. Dan D'ag designs have been that .. Concrete.. They seldom failed even under harsh conditions while driving ridiculous loads that would put lesser amps to their knees. A friend of mine is still using his KSA-200 after 20 years and in Haiti where electricity varies from 80 volts (!) to 150 ( in an heartbeat).. Not a cap has been changed in this amp ..
To me reliability should be at the core of the High End Experience .. many a brand who showed great promise has been undone by reliability problems .. Jadis did suffer from that IIRC among many others ...

I find the comment about Yamaha receiver quite amusing in this regard as if High End gears are inherently unreliable .. My experiences has been different and many can chime in i know Steve has Triodes amps and and they have functioned flawlessly for three years and counting ... They are tubes ... My Burmester amp, preamp, DAC and transport never failed (about 6 years of utter pleasure), until they were crushed ... literally ... High End gear are of the highest quality in general and poor reliability is the sure sign of a poor design ...

Congrats Dan on your new endeavor. I wish you greater successes than what you had with the other company

 

[caesar]

Good grief Caesar, what a laundry list of questions for Dan

Almost makes one think that you are trying to goad Dan in some way
BTW, just because an amp is highly powerful, doesn't mean that it has to sound good, in fact IME, the higher the power, many times the worse the sound. If Dan's amp has enough power to drive your speakers, which it should IF you are using any speakers that are a REASONABLE load, then that is all it needs. OTOH, if you are using Apogee's or the like, well look for another amp

So, in other words, i think the quality and sound of an amp has NOTHING to do with its ability to put out power 2nd BTW, I have heard MF's beloved Musical Fidelity amps, they did absolutely nothing for me

No such thing, DaveyF! I am just looking for the facts, his opinions, and to learn something. Just like you shared your sthoughts, I would like to know where Mr. D'Agostino is coming from. Kessler kind of failed us in his review.

 

[microstrip]

(...) A friend of mine is still using his KSA-200 after 20 years and in Haiti where electricity varies from 80 volts (!) to 150 ( in an heartbeat).. Not a cap has been changed in this amp ..

But probably the sound of the amplifier would improve if he changes the electrolytic capacitors!

As I have owned a KSA-100 I would like to add a comment. As it used internal fans with a pipe type heat-sink, the old KSA series run rather warm than hot as the next Krell generation, and the electrolytic capacitors can last longer. However, the red plastic encapsulated Roederstein capacitors it uses should be now at the end of their life - better replacing them now then after they become faulty. When the capacitors of my KSA-100 were replaced their were measured and one of them had a capacity of around 30% of nominal value, some others around 60%.

You can see some information about refurbishing in this link:
http://home.ca.inter.net/~lloyd.maclean/Krell/Krell.htm

 

[Orb]

Good grief Caesar, what a laundry list of questions for Dan

Almost makes one think that you are trying to goad Dan in some way
BTW, just because an amp is highly powerful, doesn't mean that it has to sound good, in fact IME, the higher the power, many times the worse the sound. If Dan's amp has enough power to drive your speakers, which it should IF you are using any speakers that are a REASONABLE load, then that is all it needs. OTOH, if you are using Apogee's or the like, well look for another amp

So, in other words, i think the quality and sound of an amp has NOTHING to do with its ability to put out power 2nd BTW, I have heard MF's beloved Musical Fidelity amps, they did absolutely nothing for me

Looking at Paul Miller's measurements/comments, it looks like the Momentum can drive any speaker (handles down to below 1ohm), with the sound quality being uniform from output impedance-loading performance perspective.

Cheers
Orb

 

[fishnchips]

Since Mr. D'Agostino freely admitted that the samples distributed for review were defective, some questions arise. Was he aware of the defects? If not, this means that the samples were not subjected to proper quality control, both objectively (via measurements) and subjectively (via auditioning). Since companies such as his take pride in painstakingly perfecting their products through exhaustive listening tests, such a lapse would mean either that such tests were not carried out, or that they were carried out and failed to pick up the defect. The former seems highly unlikely, as pre-production models are assembled for this very reason: to identify defects in a timely fashion. There is one more possibility: that the defect was picked up in time, but they decided to send the samples out for review nevertheless. This would have meant risking a bad review. Why would someone take such a risk, unless they knew beforehand that a bad review would not be forthcoming? If these defective samples were meant to be hand-outs, one would be justified in jumping to the conclusion that reviewers were actually bribed with free amplifiers, which they could at a later time sell to unsuspecting victims. I am not willing to go as far, but would rather give Mr. D'Agostino the benefit of the doubt. I'm sure he will be able to explain everything in a manner that will be substantively and ethically satisfying to all.

 

[MylesBAstor]

Since Mr. D'Agostino freely admitted that the samples distributed for review were defective, some questions arise. Was he aware of the defects? If not, this means that the samples were not subjected to proper quality control, both objectively (via measurements) and subjectively (via auditioning). Since companies such as his take pride in painstakingly perfecting their products through exhaustive listening tests, such a lapse would mean either that such tests were not carried out, or that they were carried out and failed to pick up the defect. The former seems highly unlikely, as pre-production models are assembled for this very reason: to identify defects in a timely fashion. There is one more possibility: that the defect was picked up in time, but they decided to send the samples out for review nevertheless. This would have meant risking a bad review. Why would someone take such a risk, unless they knew beforehand that a bad review would not be forthcoming? If these defective samples were meant to be hand-outs, one would be justified in jumping to the conclusion that reviewers were actually bribed with free amplifiers, which they could at a later time sell to unsuspecting victims. I am not willing to go as far, but would rather give Mr. D'Agostino the benefit of the doubt. I'm sure he will be able to explain everything in a manner that will be substantively and ethically satisfying to all.

Actually there's another reason that you didn't consider.

 

[Orb]

Since Mr. D'Agostino freely admitted that the samples distributed for review were defective, some questions arise. Was he aware of the defects? If not, this means that the samples were not subjected to proper quality control, both objectively (via measurements) and subjectively (via auditioning). Since companies such as his take pride in painstakingly perfecting their products through exhaustive listening tests, such a lapse would mean either that such tests were not carried out, or that they were carried out and failed to pick up the defect. The former seems highly unlikely, as pre-production models are assembled for this very reason: to identify defects in a timely fashion. There is one more possibility: that the defect was picked up in time, but they decided to send the samples out for review nevertheless. This would have meant risking a bad review. Why would someone take such a risk, unless they knew beforehand that a bad review would not be forthcoming? If these defective samples were meant to be hand-outs, one would be justified in jumping to the conclusion that reviewers were actually bribed with free amplifiers, which they could at a later time sell to unsuspecting victims. I am not willing to go as far, but would rather give Mr. D'Agostino the benefit of the doubt. I'm sure he will be able to explain everything in a manner that will be substantively and ethically satisfying to all.

I think you are over-reacting here, the product still sounded amazing according to those who heard it, and it measures extrememely well apart from the noise, which while you say was defective required minor revision that many early sample products do.
As an example the well reviewed Devialet D-premier was reviewed as an early sample and in doing so the analogue sampling had problems, but for actual production this was resolved.
Some products are reviewed early due to the interest given into the product; whether it relates to design or the engineer, but usually the consistent aspect is that these products sound amazing even pre-production and hence the push to review.

You may argue they wait to review, but as a subscriber to many magazines I am not that bothered as long as they mention the product is an early sample and point out niggles they identify, in this case the hum-noise is a niggle due to shielding considerations and not a defect (appreciate some will argue this on semantics thought).

Thanks
Orb

 

[mep]

fishandchips is way over-reacting. He's ready to be judge and jury and put Dan on trial. The one thing that I find interesting is that I thought it was the policy of the major stereo rags to not review prototypes just for these types of reasons.

 

[mauidan]

fishandchips is way over-reacting.

That's an understatement.

 

[Orb]

fishandchips is way over-reacting. He's ready to be judge and jury and put Dan on trial. The one thing that I find interesting is that I thought it was the policy of the major stereo rags to not review prototypes just for these types of reasons.

That is Stereophile, which also includes the X dealers requirement as well if I remember.
Usually Hifinews and a couple of others do not review early samples, however it comes back to the amount of interest in a product that pushes it to be reviewed, as long as they mention it is early sample I cannot see a problem with this - the review of the Devialet did not stop sales even though it was made known further development was coming and that at the time of the review the analogue sampling seemed to be a problem.
Myself and Bernard were early adopters of these products and while I cannot comment for him, I knew that purchasing very early models can have its own headaches, the trust I guess is in whether they become resolved-tweaked, which we can see has happened with the Momentum (and also the Devialet).

But yeah your right, its rare for very early products to be reviewed, still I am glad that the good ones are tbh as it makes being a subscriber of various audio mags interesting.
Cheers
Orb

 

[fishnchips]

I think you are over-reacting here, the product still sounded amazing according to those who heard it

This has not been proven yet. For the time being we are trying to find if the reviewers were impartial in their assessment or not.

 

[mep]

It's not clear to me how you think you are going to be an investigative journalist and get to the bottom of what you perceive to be some type of scandal. Is there a method to your madness or are you just going to continue to throw wild accusations around?

 

[fishnchips]

"Madness"? I think my questions are perfectly reasonable.

 

[mep]

I think they are perfectly accusatory with nothing to back up the allegations.

 

[fishnchips]

Which is not what I wrote:

I'm sure he will be able to explain everything in a manner that will be substantively and ethically satisfying to all.

However my personal beliefs are no substitute for public perception. Therefore I'm certain that a satisfactory explanation is forthcoming.

 

[MylesBAstor]

Which is not what I wrote:However my personal beliefs are no substitute for public perception. Therefore I'm certain that a satisfactory explanation is forthcoming.

The real and only question is this: why did the EIC choose to publish a review where the product suffered from hum problems w/o sorting out the problem?

There's no other mysterious conspiracies here: basically, HFN was trying to scoop the world with a review of Dan's amplifier and had access to from the UK distributor.

And as Dan has told us, the problem is a problem no more.

 

[amirm]

Guys, no more personal comments. Let's move on.....

 

[fishnchips]

HFN was trying to scoop the world with a review of Dan's amplifier and had access to from the UK distributor.
And as Dan has told us, the problem is a problem no more.

A PDF of the review is available from Absolute Sounds. There is a sentence by Miller about "fractionally high hum and noise in this early sample" in the measurements box. Reading the subjective report makes it plain that this was a problem that Mr. Kessler either failed to detect or failed to disclose.

 

[Orb]

There only needs to be one disclosure fishnchips and does not matter whether it is the reviewer or the one doing the measurements.
In this instance it was the measurements, if you were a subscriber to hifinews you would see how such early samples are handled, and always there is a disclosure but can be the reviewer when everything measures fine, and other times PM.
Cheers
Orb

 

[fishnchips]

Sorry, your syntax is too complicated for me to follow. The way I see it, If a measurement reveals a possible problem, the onus is on the reviewer to discuss how audible it is. That's what they are paid for. Especially so for gear that costs an arm, a leg, a spleen and possibly an adrenal or two.