No it auto turn off to enter standby mode and turns on when receive signal from RCA or xlr input
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"Stand/Evidenced"? They are simply subjective impressions. They neither "stand"- they can neither be proved or disproved, nor are they "evidence" of anything.
It's not about the device, it's about the implementation. Clearly Hypex and Purifi have shown that with proper implementation, silicon FET's can perform exceptionally well. If you want to follow the marketing flavor of the day and buy an amp with a better performing fet implemented in a poorer performing design such that the end result is not state of the art, well, go for it.
These graphs tell us nothing about the frequency response with variations in load impedance. Since nearly all speakers have a varying impedance with frequency, a flat frequency response is a desired performance target. This amp is almost certain to have no post filter feedback (the manufacturer first said it did, then said it didn't), meaning it will not have a flat frequency response with varying load. That issue has been solved for 20 plus years. Again, the marketing department is driving this bus. I can't imagine why anyone would have any interest in a class d amp with last century design.
Sokel
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I'm sure Amir has got this, months ago.
Except they didn't send it because of its low performance?
Thank you, you will need to discus the graphs with SMSL, won't you? as that is all we have, isn't it? We are looking forward to the ASR measurements via @amirm (if possible), aren't we?
Sokel
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SMSL sends its stuff to Amir for review regularly, he wrote once that this summer was receiving one every month.
So chances are that its already on his backlog.
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He has not received one yet. I offered one of mine for him. He said he wants to test one due to the level of interest, but is checking first with one of SMSL’s resellers to see if they’d send him one, to avoid hassle on my part (very nice of him).
So at the moment, he has every intention of testing one, but hasn’t a unit on hand yet, and will get one either from me or from a reseller, and has/will not get one from SMSL.
-Ed
@EddNog, thank you and very nice of you, thank you and very nice of @amirm. The SMSL graphs suggest that the measurements will not be the level of Hypex/Purifi/Topping B100/B200/etc, don't they? but the ASR/@amirm Test/Measurements will reveal the unknown (for an objective discussion/s with objective interpretations/impressions), won't they?
edit: note that you do not need me to be involved in the (objective) discussions (edit: without Angst is always the best Way, isn't it?) but know that I will be (eagerly) reading them :=)
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No, I don't need to discuss with SMSL. I already know the amp doesn't have post filter feedback which means the frequency response will vary with load impedance. Outdated design. No thanks.
Thank you but could it have a form of this?.... 'SMSL P200 GaN amplifier utilizes a closed-loop design with post-filter feedback'
That was their AI reply to my inquiry, which was superseded by a subsequent reply from a human who stated that no, it does not have post filter feedback.
Roland68
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It seems to me that SMSL sorts out which devices they send to Amir very well.
ASR now has a wide reach, and an amplifier review that lands in the middle or lower green area of the SINAD list could have a significant impact on sales figures. The same applies to reviews and discussions about frequency response and load impedance dependency.
Considering how many DACs SMSL, Sabaj, and Loxjie have sent Amir for review, it's striking that these companies have sent a total of two amplifiers for review in the last five years.
Two in five years out of at least 35 amplifiers, and neither of them was Infinion-based (although that makes up the majority).
I find that very noticeable.
In addition, there are six other reviews of SMSL, Sabaj, and Loxjie amplifiers, two of which were sent by dealers and four by members.
I am interested in your post,
1. what exactly are you're arguments behind your statement that the PA200 has a poorer performing design? Do you have the exact measurements?
2. what is your argument behind your statement the the end result is not 'state of the art'. Why is a GanFET without feedback not more 'state of the art' than Silicon with feedback? Who or what determines 'state of the art'. Does state of the art also imply the generation of heat (the temperature of the device) Is 'state of the art' GanFET implementation or the art of feedback? Is it the fysical size of the box compared to the output? Or do we have to conclude first which measurement ranks highest and do we need consensus about this first? Is it signal to noise ratio or the weight in kilograms of the amp?
I understand ASR has it's hierarchy in the measurements (list of 'dead time' in nanoseconds excluded) But perhaps the PA 200 starts at a lower point at z. B. the SINAD listings but pushes designs in a new direction with GaN and therefore is more 'state of the art' even thought the measurements still are less by now. State of the art doesn't always mean better.
So It's not just about following the new market flavour. It's also about looking where new implementations can bring us.
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Roland68
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I find weight in kilograms very important.
The heavier the amplifier, the lower the risk of it being stolen
.Class d amplifiers without post filter feedback have a load dependent frequency response. You don't need measurements as it is a product of the design. Load dependent frequency response was an issue with early class d amps (see Tripath). Once designers started using a post filter feedback point, this issue was resolved. See Hypex, Purifi, Orchard, etc., all using post filter feedback and as a result, all have frequency response that is flat with varying load. The problem of varying frequency response has been solved, maybe 20 or more years ago. In comparison to the performance of the above mentioned amps, class d amps without post filter feedback, like this GaN amp and others like it (see Peachtree), perform poorly in this regard. An amplifier without load dependency, all things otherwise equal, is preferable to one with load dependency. That should be obvious. In fact, most amplifiers without load dependency also typically have lower distortion as well...
An amp design is usually judged by the end result, not by what components it is made of. I consider a "state of the art" design one that most closely meets the definition of a high fidelity amplifier: it takes a small signal and makes it larger, adding or subtracting nothing. Amplifiers with load variant frequency response were superseded by a superior design- one that does not have load dependent frequency response, . Heat, form factor, weight, etc., are secondary to the primary objective of most amp designers: to creat a wire with gain. GaN is a state of the art FET but clearly, at present, simply using a GaN FET does not make an amp state of the art. It's the implementation, not the parts, that matter. Perhaps you have a different idea about what "state of the art" means. I assume something that is "state of the art" is at the pinacle, or limit, of current knowledge and capabilities, something that performs at the limit of current capacities.
Most of the amps using GaN FET's have not met the performance levels of, as I have said, state of the art class d amps using standard FETs. Most of the marketing copy has focused on their advantages (dead time, less heat, more efficiency, etc.) though as has been discussed by industry experts like Bruno Putseys and others, few if any manufacturers touting GaN FET amps have actually brought to market a GaN FET amp that actually exploits those advantages in any material way and few (any?) actually perform as well as standard FET amps by Hypex, Purifi, etc. This is why it is a "flavor of the day" marketing scam.
Thanks for your reply. It really helps me to understand the different arguments. Indeed I listened to putzeys discussion about the sub 150 volt and 10dB distortion margins etc compared to good feedback designs. But personally i was curious about this dead space time issue. Perhaps it s just a marketing issue and you are fully right. I am listening to the NAD c298 eigentakt and the PA200 now for a couple days just to figure this out for myself.
Thanks again for your reply
Thanks again for your reply
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If you do a google search you can find an interview wherein Bruno and Lars discuss GaN fet's and why they haven't felt the need to use them. There are some serious technical reasons why their advantages over silicon fets aren't easily exploited in audio amplifiers.
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