Hello @muduceHi 3eaudio
You recommend here and distribute (ALIEXPRESS) LOF350-20B48-C and LOF500-20B48-C power supplies.
Can you provide us with measurements concerning the noise of these, a bit like those made by LESTER (SYLPH AUDIO) on AUDIO SCIENCE REVIEW
(thread "JL ELectronics Sylph-D200 Amplifier Module Review", post #193) ?
This would allow us to have a better view of the quality of these power supplies and would indirectly impact your sales
Thank you in advance
Cordially.
i did a fast test as here,this power supply not same as the one you mentioned.
Attachments
Hi 3eaudio,
nice to 'meet' you
I thank you about your answer
Can you use the same scales like AMIRM on ASR ->
It is not easy for everyone to convert µVrms to dBrA of your measurements : it would be better understood by all readers
( original link -> https://www.audiosciencereview.com/...ics-sylph-d200-amplifier-module-review.25295/ )
Thank you in advance
IMPORTANT:
has the relay noise problem encountered on the SABAJ A20a amplifier (which has the same type of power supply) been solved ?
Indeed, users had to remove this power supply to replace it with a MEANWELL SMPS...
nice to 'meet' you
I thank you about your answer
Can you use the same scales like AMIRM on ASR ->
It is not easy for everyone to convert µVrms to dBrA of your measurements : it would be better understood by all readers
( original link -> https://www.audiosciencereview.com/...ics-sylph-d200-amplifier-module-review.25295/ )
Thank you in advance
IMPORTANT:
has the relay noise problem encountered on the SABAJ A20a amplifier (which has the same type of power supply) been solved ?
Indeed, users had to remove this power supply to replace it with a MEANWELL SMPS...
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I do not have a good/suitable measurement setup for electronics, only for speakers. Also the amps are not yet built. I am currently ordering all the necessary thru-hole chassis connnectors and placing the chassis orders with ModuShop.@ CharlieLaub
Indeed: the MEANWELL UHP-350R-48 power supply would seem to be suitable with 7.3A for a maximum of 50°C and even hotter if it is attached to the chassis according to the manufacturer's technical sheet !
Have you already made measurements with this power supply ? 👈
@ CharlieLaub,
Alright.
I wish you good luck with your project
In the meantime, I found measurements made by MEANWELL regarding the UHP-350R-48 power supply, here is the link ->
https://www.meanwell-web.com/content/files/pdfs/productPdfs/MW/UHP-350(R)/UHP-350-48-rpt.pdf
This power supply seems really very interesting in view of its characteristics
Too bad we don't have the FFT curve
If only someone had one and could perform it, unless we have the chance that MEANWELL reads this forum: you never know
Alright.
I wish you good luck with your project
In the meantime, I found measurements made by MEANWELL regarding the UHP-350R-48 power supply, here is the link ->
https://www.meanwell-web.com/content/files/pdfs/productPdfs/MW/UHP-350(R)/UHP-350-48-rpt.pdf
This power supply seems really very interesting in view of its characteristics
Too bad we don't have the FFT curve
If only someone had one and could perform it, unless we have the chance that MEANWELL reads this forum: you never know
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Hi TNT
FFT of the power unit.
The efficiency of the MEANWELL UHP-350R-48 power supply is exceptional in view of the high ambient temperatures possible in use and its low derating
Why did you say: "It seem to be a fairly average power unit? 85mV ripple/noise..."
(The MORNSUN have 200mV for exemple...)
So, can you argue by showing us better units that you have tested and measured please ?
This would be really interesting for anyone who has a DIY project with the TPA3255
FFT of the power unit.
The efficiency of the MEANWELL UHP-350R-48 power supply is exceptional in view of the high ambient temperatures possible in use and its low derating
Why did you say: "It seem to be a fairly average power unit? 85mV ripple/noise..."
(The MORNSUN have 200mV for exemple...)
So, can you argue by showing us better units that you have tested and measured please ?
This would be really interesting for anyone who has a DIY project with the TPA3255
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89mV @ 5A for your exemple (CONNEX SMPS300RE)...
... page4: "For other applications than audio, where the power supply must deliver more than 100W for long term, the SMPS300R must be fitted with a heatsink or active cooling should be used."
The continuous power available seems really lower and would be obtained with a significant heating of this power supply.
-> the MEANWELL 84.8mVp-p @ FULL LOAD
And this MEANWELL SMPS is PFC
Show page 7 too, SMPS300R can't say the same, that's for sure ('open' supply)
In addition the price difference between its two power supplies is really not huge.
I have also noticed that some users have had manufacturing and/or reliability issues with this power supply.
I am not at all convinced of the quality of this one contrary to the arguments used by the resellers...
... page4: "For other applications than audio, where the power supply must deliver more than 100W for long term, the SMPS300R must be fitted with a heatsink or active cooling should be used."
The continuous power available seems really lower and would be obtained with a significant heating of this power supply.
-> the MEANWELL 84.8mVp-p @ FULL LOAD
And this MEANWELL SMPS is PFC
Show page 7 too, SMPS300R can't say the same, that's for sure ('open' supply)
In addition the price difference between its two power supplies is really not huge.
I have also noticed that some users have had manufacturing and/or reliability issues with this power supply.
I am not at all convinced of the quality of this one contrary to the arguments used by the resellers...
It's not clear to me why one would care all that much about SMPS ripple voltage. Although class-D amplifiers do not have very high PSRR, you have to consider the frequency of the ripple. This quote is taken from a TI app note about PSRR:
https://www.ti.com/lit/an/slea049/slea049.pdf
Also, from the TPA3255 datasheet: ">65 dB PSRR" at 1kHz.
What is the problem here???
Source:
https://www.ti.com/lit/an/slea049/slea049.pdf
Also, from the TPA3255 datasheet: ">65 dB PSRR" at 1kHz.
What is the problem here???
@ CharlieLaub
Who can do more can do less
I think that just like for tube amplifiers, the role of the power supply is essential...
In addition, the harmonic distortions (the human ear, or the brain?, is very sensitive to it) generated by your power supply will inevitably end up at the output of your amplifier in a certain way, right ?
That's why I was insisting on getting the FFT from the MEANWELL power supply
We have only the MORNSUN's ->
Too bad this FFT is not identical to those produced by Audio Science Review...
Who can do more can do less
I think that just like for tube amplifiers, the role of the power supply is essential...
In addition, the harmonic distortions (the human ear, or the brain?, is very sensitive to it) generated by your power supply will inevitably end up at the output of your amplifier in a certain way, right ?
That's why I was insisting on getting the FFT from the MEANWELL power supply
We have only the MORNSUN's ->
Too bad this FFT is not identical to those produced by Audio Science Review...
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NO. Because the switching frequency of the SMPS is pretty high (a few hundred kHz) this ripple on the PVDD rail DOES go thru the amplifier chip but is filtered out by the amplifier's lowpass output filter, so it never reaches the output terminals. That was the point I was trying to make.
Linear PS ripple is all within the audio band so that WOULD come out of the amplifier at the output terminals.
Linear PS ripple is all within the audio band so that WOULD come out of the amplifier at the output terminals.
@ CharlieLaub,
OK then why in this case manufacturers like HYPEX, PURIFI, and I forget some, do not use 'dirty' (or simples) power supplies and instead try to use good ones for their assemblies ?
Is it just commercial and/or to earn as much money as possible ?
Or are these 'people' just plain stupid ?
I do not believe...
OK then why in this case manufacturers like HYPEX, PURIFI, and I forget some, do not use 'dirty' (or simples) power supplies and instead try to use good ones for their assemblies ?
Is it just commercial and/or to earn as much money as possible ?
Or are these 'people' just plain stupid ?
I do not believe...
I think that initially we are here to think about it and that they must undoubtedly be interested closely in what can be written on this type of forum.
With a bit of luck, we may have the intervention of one of them...?
3e audio has at least had the 'courage' to publish measures that may interest a certain number of us:
we can thank them and encourage them in this ('transparent') way
They just need to be more precise in their presentation and use units and scales comparable to those of Amirm by ASR, which is widely followed by manufacturers like LESTER from SYLPH AUDIO did
With a bit of luck, we may have the intervention of one of them...?
3e audio has at least had the 'courage' to publish measures that may interest a certain number of us:
we can thank them and encourage them in this ('transparent') way
They just need to be more precise in their presentation and use units and scales comparable to those of Amirm by ASR, which is widely followed by manufacturers like LESTER from SYLPH AUDIO did
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