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Cheap class D amps. Andrew Robinsons take.

Mackie

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Has anyone else watched this video on cheap class D amps ? Made me think twice about purchasing one.

 

VintageFlanker

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Has anyone else watched this video on cheap class D amps ?
Why would anyone on ASR watch something from Andrew Robinson to begin with?

Made me think twice about purchasing one.
You should think twice about the YouTubers to watch instead. :p
 

fpitas

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I got lost in all the measurements and math.
 

fpitas

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But that man can certainly wave his hands. I'm convinced!
 

JSmith

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I skimmed the video... he's correct about one thing, which is these cheaper amps are advertised with way over the top power ratings. Often it's also unclear to the consumer that they may require a different power supply to get remotely close to the "rated" power.

Apart from that the rest seemed rather subjective in general, especially this part;


JSmith
 

fpitas

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I skimmed the video... he's correct about one thing, which is these cheaper amps are advertised with way over the top power ratings. Often it's also unclear to the consumer that they may require a different power supply to get remotely close to the "rated" power.

Apart from that the rest seemed rather subjective in general, especially this part;



JSmith
Yes, many do need a bigger supply to generate continuous rated output. I wonder whether you will still get the peak output with the included power supply. That really would be good enough for listening to most music.
 

Sokel

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Yes, many do need a bigger supply to generate continuous rated output. I wonder whether you will still get the peak output with the included power supply. That really would be good enough for listening to most music.
They would need bigger case and heatshinks for continuous.
I know you know it I just highlight it cause some folks may think that the PSU will all they would need for higher continuous output.
 

fpitas

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They would need bigger case and heatshinks for continuous.
I know you know it I just highlight it cause some folks may think that the PSU will all they would need for higher continuous output.
You are most likely correct, but then the vast majority will never use it anywhere near the maximum continuous output. Still, I suppose it is shady marketing.
 

tomtoo

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Absolutly clear listening at 75dB in 4m distance is much less harmfull like listening to 75dB at 80cm!! HeHe.

All this is so boring useless. If a measured 100w amp has less umpf then a measured 25W amp. He should look at the output voltage of his source.
 
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Sokel

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You are most likely correct, but then the vast majority will never use it anywhere near the maximum continuous output. Still, I suppose it is shady marketing.
Imagine if I have put that in a small case (my installers wouldn't let me anyway) :

heat.PNG
 

Rick Sykora

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Despite the click bait title, this video seems to be about admitting that he may have been mistaken in recommending many of these amps in the past. There is no explanation of why he failed to hear the alleged “high frequency skew” previously. If I had followed his advice in the past, would either be upset that he failed to identify these alleged shortcomings sooner or question his motivation for his sudden change of heart. Was also not clear that he had any better recommendation than to save up and spend on something ”better”.:confused:
 

JSmith

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I wonder whether you will still get the peak output with the included power supply.
Well when Amir tested Fosi for example, even with the larger 48V PSU, it still didn't get anywhere near the 300W x 2 @4R that they advertise. I'm not singling them out here though, it's common for all those that use the TI chip amps;

index.php


That said this is decent power... but I just wish those companies would be a little more transparent in describing max output power (plus not at 10% THD+N). There is no need to mislead with decent measurements and power output, but of course this is often not uncommon in general across the whole industry.


JSmith
 

tomtoo

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Well when Amir tested Fosi for example, even with the larger 48V PSU, it still didn't get anywhere near the 300W x 2 @4R that they advertise. I'm not singling them out here though, it's common for all those that use the TI chip amps;

index.php


That said this is decent power... but I just wish those companies would be a little more transparent in describing max output power (plus not at 10% THD+N). There is no need to mislead with decent measurements and power output, but of course this is often not uncommon in general across the whole industry.


JSmith

Yes its not nice. The good thing is we have measurements. Yes they just take what TI tells.
 
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Talisman

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Has anyone else watched this video on cheap class D amps ? Made me think twice about purchasing one.

The real added value of a site like ASR is that it doesn't tell you what to buy, it teaches you to read all the measurements and make your choice in an informed way.
I bought things not recommended by Amir and refused things recommended.
This is the best testament to the work Amir has done with this site. He doesn't need to feed us, he taught us to cultivate the land.

Here we don't need a reviewer to tell us what to buy and why, we need accurate measurements to determine for ourselves if that product is right for us
 

fpitas

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Well when Amir tested Fosi for example, even with the larger 48V PSU, it still didn't get anywhere near the 300W x 2 @4R that they advertise. I'm not singling them out here though, it's common for all those that use the TI chip amps;

index.php


That said this is decent power... but I just wish those companies would be a little more transparent in describing max output power (plus not at 10% THD+N). There is no need to mislead with decent measurements and power output, but of course this is often not uncommon in general across the whole industry.


JSmith
Agreed they do shade the truth. Maybe a lot. If I was on a budget though, I think I'd still be happy with that.
 

diablo

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I've run my lounge floorstanders with a Yamaha R-N803, Aiyima A07 with standard PSU and currently an SMSL A300.

I ran some REW tests where I just swapped out the amps, leaving the microphone in an identical place - there was no difference in the output graphs, either in frequency response, impulse, distortion etc.

At my maximum listening level the A300 draws about 15 watts - and five of that is used with no input. My speakers are 85dB efficiency and I sit approx 11 feet away. The A07 was similar, though drew less at idle. So unless I want my neighbours to hear what I'm playing then the A300 desktop amp is more than adequate. :)

I reckon he doesn't want to stop manufacturers sending him expensive gear - if he's going to say that the cheapo stuff is just as good. :D
 

fpitas

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