Pay rise.
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Devialet Expert 200 Amplifier, DAC and Streamer Review
- Thread starter amirm
- Start date
Maybe it was the sippin rye ...
Remember class D is not digital, it's an analogue amp class.
In this product it's not because it's a class A / class D hybrid that makes it digital, it's the architecture of the whole product that makes it digital before the amp, if they used a pure class A amp after the DAC it would be similar.
Could be that and the toons relaxin me so muchO.
If they close the liquor stores it's gonna be a pain!
Gotcha on the system wide digital protections. I figured from your commentary that you meant the class D amps can be better-faster controlled before a major issue arises. Can they comparatively?
No idea on the class D thing, or how the ADH might offer advantages, it's their architecture that offers faster protection, because it can protect before amplifying whilst it's still in the digital domain.
On topic but off topic. I remember the very first integrated amp that I bought new. A Technics SU-V303. The protection circuitry was so good i used it for ~10 years before I turned it into a bench test amp. I would short out the speakers leads and show off the protection circuitry. It finally died a silent death about 15 years later. It was a great amp for it's life time and cost.
ADH?
Perhaps @March Audio could chime in on the potential speed of the protection circuitry in class D amplifiers? Is it comparatively faster than a class A/B protection circuitry? What are the advantages? Get a expert here on the matter.
Class A, Class D Hybrid.
AHhhh rightO. Thank you.
Well the protection is pretty comprehensive on the Hypex modules, and yes its quick.
Havent got musch time so I will chop a bit out of the NC1200 manual.
7.1 Firmware operation
The microprocessor has three main functions: to provide an interface for controlling the amplifier, to
monitor the supply voltages in order to prevent spurious operation during power up/down and to
detect error conditions. Most errors clear automatically as soon as the error condition lifts. The
exception is a fatal DC fault, this almost certainly stems from a broken power FET. The FATAL signal
should not be cleared externally. Instead the +/-HV supplies must be shut down immediately to
prevent or mitigate damage to attached loudspeakers.
The FATAL error is also sent to the PSU to shut it down. The PSU also has over current and error sensing
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That's pretty comprehensive protection circuitry. The +/- 101V over voltage and 85-95 Celsius protection limits combined with the 34-38-40 Amp current limit is pretty rigorous.
One can only guess that this is not full of small gauge digital transistors and tiny fused resisters and the speed of cutting off the switched mode PWM power supply current after the 0.5 second DC sensed mode is much faster than a linear power supply draining into a class AB or ADH circuit that has a fault/short. I thought the DC sense mode would be smaller than 0.5 seconds but if this is it then that's what is required from the designer(s).
The Devialet circuitry parameters would be interesting to see.
Thank you for the prompt reply @March Audio
Tks
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Just quickly since I've been following this, and have largely sided with your line of replies and want to quickly address two portions. The first thing about Devialet giving guidance on testing. No one needs guidance on testing, as these tests have rarely caused any issues on all other amps. Also this isn't some vintage product that would be lacking protection circuits or something (and the stupidity of doing such today on a device that is essentially 5-figures is lunacy). There is no reason why this thing should croak and die. We don't want to do tests "they recommend", these are tests conducted that aren't torture tests trying to gauge points of total failure.
So unless I am misunderstanding the argumentation, I don't know why anyone would, ever... AT ALL, consult a manufacturer, ESPECIALLY of this caliber, on if their amp would survive tests all other amps have up until now (unless I am missing some from before I joined or something). Especially if they had the balls to post proper specs that would allow us to see if there were any red flags in testing for whatever reason.
The second is, it should be a priority for them to address this problem even if it was Corona, and Bubonic plague making a return at the same time. That doesn't mean they have to fix the device and address all the specific issues with the unit and apply fixes for all amps going forward. No, what is expected is confirmation they are willing to do so, in light of the pathetic failure the amp itself is. It doesn't matter if this gets done in three days, or three weeks (everyone understand the pragmatic issue with logistics currently, and people/customers are willing to grant leniency, as they should). It's a whole other thing to turn around and say nothing, or "we'll get to it whenever Corona is done, and then we'll see if we want to address this at a later time".
The only 'onus' on them to move faster, is their own PR. If they want to be thrown into the pile of pseudo luxury brands (brands that don't fulfill half of what I understand luxury to be, and that is customer support/satisfaction in spite of mainstream economic realities for other companies that MUST skimp on this in order to be economically viable, but companies like Devialet are charging enough to where they are expected to take this loss, and go against the grain and offer better customer support than the mainstream company that simply can't afford it due to competition). So if they want to fulfill the stereotype that has more times than not rung true for these "higher-end" companies.. They can go down the line of your rationale of not having to do anything perhaps in some case even. If they want to gamble, and give detractors ammo for besmirching them further than their own products already have.. Well then they are just run by morons plainly put in my book.
And finally, just do the calculous. How difficult would it be to do what companies from the East (like Topping and SMSL have done a few times) and with barely functional language offer to fix entire SKU's of products anytime there was a problem.. No one here is asking much, certainly not from Devialet who's owner's head is so far up his ass, you would think the man is sailing on blissful oceans of cash. All that would need to be done is start hasty communication channels, bite the bullet on fixing this unit (while still leaving room to be cowards and not revealing the actual extent of what known issue allows for malfunctioning like this unit underwent), and all would be well. You placate the masses of on-lookers, while fixing a problem that is otherwise going to cause lots more damage than a simple unit fix..
So aside from those two aspects of your post, I'm with you on everything else.
With DPM turned off, it will work much much better
Well it couldn't work much worse after this testing.
In my (admittedly limited) experience of attempting to test stuff to destruction, an absolute short circuit is a lot easier to manage than a long-term marginal position.
Shall I? Shan't I? Shall I? Shan't I? Shall I? Shall I? Shan't I? Shall I? Shan't I? <PUFF> Oh dear.
mhardy6647
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I think "someone" should invest in a pair of the old (late-70s/early-80s) Polk Audio "Cobra Cables" (also sold as "SoundCables" -- and maybe originally the product of another company before Polk acquired the product?). They were fairly reactive cables and, at the time, were notorious for toasting marginally stable amplifiers.
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source: https://www.stereophile.com/features/709/index.html
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Okay, I'm gonna bend on my intention not to post anything further on this thread. I will not present any new arguments/points. But I will clarify/explain/retract previous posts, for example if someone asks me a direct question, and I will ask an occasional question about someone else's post.
If I may, I'd like to start by clarifying a general point that relates to Amir's exasperated questions in the post to which I'm replying. I often say "you" as shorthand for ASR more broadly -- for example, opinions that I've seen expressed by many people on ASR. I think this kind of shorthand is pretty common in conversational discourse such as internet posts. It may not be as precise as a phrase like "many ASR posters," but it’s also less clunky.
Thus, I wrote this: "You think Devialet is trying to silence you." That sentence uses shorthand to say "Many ASR members think Devialet is trying to silence the views widely held by ASR members." That's a god-awfully wordy way to get across what I assumed was a fairly innocuous point about ASR members' very frequently expressed view of themselves as feisty "outsiders" challenging sloppy subjectivism. I'm leaving aside the other innocuous point, which is about the widespread perception that subjectivists like Devialet hope no one in their market demo will hear ASR's voice.
But when Amir read this, he thought I was ascribing to him, personally, the belief that Devialet wants to silence him, personally. I'm not sure how this could even be possible -- a hit man perhaps? A reading this tortured would get a freshman English paper marked down a grade.
On the occasions when I did intend to refer to a specific person, I tried to be reasonably careful to show that I was doing this, by using a proper name or an identifying phrase. Again, this usage is standard in natural English and quite common in internet exchanges. I would like to think it's possible to make such distinctions without resorting to legalese like "Party A."
I hope this is helpful.
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