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SMSL SA400 Review (Power Amplifier)

gasolin75

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I am using it for two weeks, and sometimes(from the first day I received it), the green VOL turns into yellow PRT. In this case, I only can hear from one side or none. Does anyone know what is the meaning of it and what happens? Is it an ordinary happening, or did I receive the broken one? View attachment 145584

WOW can't you figure that out by yourself ???????

Thats so easy, the amp is getting hot,overloaded
 
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Rottmannash

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Then what does "PRT" stand for?
 

Toku

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I am using it for two weeks, and sometimes(from the first day I received it), the green VOL turns into yellow PRT. In this case, I only can hear from one side or none. Does anyone know what is the meaning of it and what happens? Is it an ordinary happening, or did I receive the broken one? View attachment 145584
If you encounter any abnormal behavior, first reset it to the factory default settings.
I thought it was a warning of overheating of the amplifier, but the temperature is 53 ° C, which is not so high.
 
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gasolin75

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ken22

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It sometimes happens when it is about 30 °C. It seems like a protection mode, but why? It does not change to the normal mode automatically until I turn off the power. When it is in PRT mode, I cannot hear the sound of the inner cooling fan. It is why I am confusing.
KakaoTalk_Photo_2021-08-06-01-17-38.jpeg
 

gasolin75

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It sometimes happens when it is about 30 °C. It seems like a protection mode, but why? It does not change to the normal mode automatically until I turn off the power. When it is in PRT mode, I cannot hear the sound of the inner cooling fan. It is why I am confusing. View attachment 145592

Has anybody said there is a fan inside of the amp ? Ventilation holes for the fan ?
 

gasolin75

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Coludn't see any fan when i googled it
 
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gasolin75

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mabye it's only for the power supply
 

DACslut

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The SA400 for a Class D amp runs too hot and requires a fan? No thanks. I'll keep my SMSL AO200 that sounds awesome, is extremely quiet, runs cool as a cucumber, puts out gobs of clean power down to 2 Ω and costs less than 3 Franklins. The AO200 is virtually hardware identical to it's DA-9 cousin and $30 cheaper. It only lacks USB and dual SW outputs. I'd gladly send my amp to Amir for testing except I can't sacrifice being without it for any length of time. Some day "when my ship comes in" I'll get one of those flagship Purifi amps.
 
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Toku

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Has anybody said there is a fan inside of the amp ? Ventilation holes for the fan ?
See this Youtube review.
A fan is attached to the position behind the main knob on the bottom plate. (time 11:24)
However, since there is no air outlet, the effect is small. Moreover, the effect of stirring the air inside cannot be expected so much.

 

ken22

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I got an official response from SMSL.

This phenomenon is because the output is too strong and the protection function is activated. The resistance of any frequency band on the speaker is so low that if the movement of the music is too high, the protection function can be activated.
Without protection, the chip can burn, so protection is compulsory and cannot be set up separately. If you turn the SA400 off, it will work normally again.
 

Vangelo

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Just bought one of these, mainly because I already had the M400 which I am impressed with. Bought direct from HiFi-Express and they paid the VAT (UK).
I had read this review and others, and the whine/noise reported did concern me. I was coming from a DEQX/Temple Audio Supercharged Monoblocks.
Unit arrived a week later, and as soon as I plugged it in, I packed it away to return. The whine was so loud I could hear it in the hallway!
I logged onto the returns page, and HiFi Express had a 35% restocking fee. Ugh...........

Ok.....set her up again and started listening through the whine. Using the balanced connectors from the M400, the sound was immediately impressive.....clean and dynamic.

Having read about the heating issue, I set about finding the fan menu to reduce from 65C to 48C. Hmm, it was already set to 45C. With continuous operation, the temperature never rose above 42C, which is perfectly acceptable to me. Even my Temples get pretty hot in operation.

......just the whine....I could not live with this. I Googled coil whine and many people said it reduces on its own. To get to the point, in my case, this turned out to be true! I have had the unit a week, and now the coil is below fan noise level which I can live with. It actually started to reduce in volume within a couple of hours.

Playing around with the presets, I like the 'clear' setting. Need to be a bit careful because the Bass, Middle & Treble controls work with the presets, and I thought there was an issue with my speakers when the mids were missing. I subsequently discovered the mids were set to -4db! This is a very versatile amp.
SA400SM.JPG


So now, the amp is a keeper. As she opens up, things are sounding better and better. The detail she retrieves has startled me on a few occasions
and the old Mono set up sounds rather boring!
 
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OP1M.DR3M

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Just bought one of these, mainly because I already had the M400 which I am impressed with. Bought direct from HiFi-Express and they paid the VAT (UK).
I had read this review and others, and the whine/noise reported did concern me. I was coming from a DEQX/Temple Audio Supercharged Monoblocks.
Unit arrived a week later, and as soon as I plugged it in, I packed it away to return. The whine was so loud I could hear it in the hallway!
I logged onto the returns page, and HiFi Express had a 35% restocking fee. Ugh...........

Ok.....set her up again and started listening through the whine. Using the balanced connectors from the M400, the sound was immediately impressive.....clean and dynamic.

Having read about the heating issue, I set about finding the fan menu to reduce from 65C to 48C. Hmm, it was already set to 45C. With continuous operation, the temperature never rose above 42C, which is perfectly acceptable to me. Even my Temples get pretty hot in operation.

......just the whine....I could not live with this. I Googled coil whine and many people said it reduces on its own. To get to the point, in my case, this turned out to be true! I have had the unit a week, and now the coil is below fan noise level which I can live with. It actually started to reduce in volume within a couple of hours.

Playing around with the presets, I like the 'clear' setting. Need to be a bit careful because the Bass, Middle & Treble controls work with the presets, and I thought there was an issue with my speakers when the mids were missing. I subsequently discovered the mids were set to -4db! This is a very versatile amp.
View attachment 183296

So now, the amp is a keeper. As she opens up, things are sounding better and better. The detail she retrieves has startled me on a few occasions
and the old Mono set up sounds rather boring!

Is the coil noise still quiet? How's the amp holding up so far?
 

jrMes1

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Hello,

I'm interested in this amplifier that I've been following for some time :)

However I would like to connect my Earmen Tradutto dac by xlr, and the kef ls50 meta speakers and the sub SVS 1000

I'm not very knowledgeable about the graphics and others measures, I try to understand, and I've seen some opinions... but nothing right, or sometimes confusing to me.

I would like to know if the amplifier meets the requirements for the speakers and the subwoofer? This amp has quality to support?

Another issue that I noticed and read in some forums has to do with excessive heating, is it confirmed?

Thank you for helping
 

Vangelo

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Hi jr

I use amp in a similar way and works fine. Quality is excellent, and compared to my TempleAudio Monoblocks (with supercaps power supply) there is more power, dynamics and detail. Its also nice to have some control over the sound with the inbuilt DSP.

My amp was noisy at first with a whine from a power coil, but that has now settled and is below the fan noise. The fan came factory set @ 45C, and rarely gets above 42C.

The only issue I have, and this could be a problem with some speakers, is if the impedance dips below 3-4 ohms and you are playing loud, the protection circuit will activate.
 

jrMes1

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Hi jr

I use amp in a similar way and works fine. Quality is excellent, and compared to my TempleAudio Monoblocks (with supercaps power supply) there is more power, dynamics and detail. Its also nice to have some control over the sound with the inbuilt DSP.

My amp was noisy at first with a whine from a power coil, but that has now settled and is below the fan noise. The fan came factory set @ 45C, and rarely gets above 42C.

The only issue I have, and this could be a problem with some speakers, is if the impedance dips below 3-4 ohms and you are playing loud, the protection circuit will activate.
Thank you for your support.

I think this will be a good pairing with Kef Ls50 meta and SVS 1000: (I hope)

Amplifier Power (Recommended)
40-100 W
Nominal Impedance
8 Ω (min. 3,5 Ω)
 
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