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SMSL SP400 Balanced Headphone Amplifier THX AAA

leben

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Ye overall this amp is definitely not too bad, it has achieved some improvements of its own from its predecessor, sp200, but just the sheer lack of responsibility of their "output power" claim and their response when they're called out for it is just repulsive.
 

Artaois

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The S.M.S.L SP400 is designed for normal 16-300 ohm headphones. The gain design also belongs to the normal range.
If the impedance is greater than 1000 ohm headphones, needs a "special high voltage, high gain, low current" amp to drive, such as a tube special amp.
When the sound source is turned on to the maximum, the volume of SP400 is generally not very low. In a normal state.
I don't even know a headphone around 1000 ohm. If I had to guess I'd say the highest people are using is the 600 ohm Beyerdynamics. The issue is that a very easy to drive Focal Elex shouldn't be on high gain at 50 while being fed by a M400 locked to 80. If the Focal requires that then I wonder if it can can power very common headphones like Sennheiser 650.
 

SMSL-Mandy

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No, Mandy. The point is you guys have claimed sp400 will have output power of 6W@32Ohm, which would drive even susvara to 115dBSPL just fine. But it seems in reality it doesn't live up to that at all. You've already did this kinda shady claim with your SH-9, which has approx. 1.7W@32ohm but was claimed to have 3W @ 32ohm. Topping as well did this with their L30. I kinda see where sbaf guys come from...
The power curve of SP400.
 

SMSL-Mandy

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The power curve of SH-9
SH-9.jpg
 

JohnYang1997

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No, Mandy. The point is you guys have claimed sp400 will have output power of 6W@32Ohm, which would drive even susvara to 115dBSPL just fine. But it seems in reality it doesn't live up to that at all. You've already did this kinda shady claim with your SH-9, which has approx. 1.7W@32ohm but was claimed to have 3W @ 32ohm. Topping as well did this with their L30. I kinda see where sbaf guys come from...
The issue with L30 is completely different. L30 has its gain structure to be more usable as no one really needs all that gain. Have any one turned the volume all the way up and still think it's not loud enough? But that's all good you will get A30pro to blow your headphones up.

The issue here is the method of interpreting power. Conventionally it's the power at 1% distortion. And Sp400 and Sh9 do meet that. Amir however uses the initial clipping point. This is not friendly/fair for low distortion amps as higher distortion amp can ease they way up with higher distortion then finally hit the "actual" clipping point.

Don't pretend that you know better because someone else you talked to says so.
 

Veri

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The issue with L30 is completely different. L30 has its gain structure to be more usable as no one really needs all that gain. Have any one turned the volume all the way up and still think it's not loud enough? But that's all good you will get A30pro to blow your headphones up.
Lately I'm having this Windows bug, sometimes at 100% volume I need to use gain 3, while most of the time gain 2 is already painfully loud. Such a wonderful OS... right :p sigh. Or it's not a OS problem and my ears are clogged LOL

The power curve of SH-9
SH-9.jpg
SH-9 matches Amir's to a T ;) Mandy what's the input voltage for both these graphs, 4V?
 

JohnYang1997

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I don't even know a headphone around 1000 ohm. If I had to guess I'd say the highest people are using is the 600 ohm Beyerdynamics. The issue is that a very easy to drive Focal Elex shouldn't be on high gain at 50 while being fed by a M400 locked to 80. If the Focal requires that then I wonder if it can can power very common headphones like Sennheiser 650.
Don't complain unless you don't have enough level at max volume settings. 12 o'clock is merely 1/4th of level and 1/16th of max power. These better designed amplifier don't have excessive high gain so you can use the full range of the volume pot. Many high gain amplifiers clip at very low output power but you don't ever get to see it clipping you thought it would have much higher power where they don't. Sp200 was partially that.
 

Artaois

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Don't complain unless you don't have enough level at max volume settings. 12 o'clock is merely 1/4th of level and 1/16th of max power. These better designed amplifier don't have excessive high gain so you can use the full range of the volume pot. Many high gain amplifiers clip at very low output power but you don't ever get to see it clipping you thought it would have much higher power where they don't. Sp200 was partially that.
You're saying that 50 on High Gain is only 1/16 of the power for the SP400 and that the rest will come from 51-99?
I admit I'm not an expert and this is the highest end product I've owned.
 

JohnYang1997

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You're saying that 50 on High Gain is only 1/16 of the power for the SP400 and that the rest will come from 51-99?
I admit I'm not an expert and this is the highest end product I've owned.
Yep. Or probably even less. That depends on the curve they use. This is done this way(by everyone) is to let you have a better range of control. You really don't want it to be ear bleeding loud at 9 10 o'clock do you?
So all in all as long as you can get your comfortable listening level. It's fine.
 

Artaois

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Yep. Or probably even less. That depends on the curve they use. This is done this way(by everyone) is to let you have a better range of control. You really don't want it to be ear bleeding loud at 9 10 o'clock do you?
So all in all as long as you can get your comfortable listening level. It's fine.
It did seem like it would be very good for sensitive IEM's because of the wide range of volume.
 

leben

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The issue with L30 is completely different. L30 has its gain structure to be more usable as no one really needs all that gain. Have any one turned the volume all the way up and still think it's not loud enough? But that's all good you will get A30pro to blow your headphones up.

The issue here is the method of interpreting power. Conventionally it's the power at 1% distortion. And Sp400 and Sh9 do meet that. Amir however uses the initial clipping point. This is not friendly/fair for low distortion amps as higher distortion amp can ease they way up with higher distortion then finally hit the "actual" clipping point.

Don't pretend that you know better because someone else you talked to says so.
oh, yeah.. pfft. "WE DID IT FOR YOU GUYS" and your answer doesn't change the fact your specification's still misleading. you're really triggered easily, aren't you?
 

SMSL-Mandy

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No, Mandy. The point is you guys have claimed sp400 will have output power of 6W@32Ohm, which would drive even susvara to 115dBSPL just fine. But it seems in reality it doesn't live up to that at all. You've already did this kinda shady claim with your SH-9, which has approx. 1.7W@32ohm but was claimed to have 3W @ 32ohm. Topping as well did this with their L30. I kinda see where sbaf guys come from...

This should be your input voltage is not big enough.
 

SMSL-Mandy

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so then why are ppl reporting "lower volume (than sp200)" issue? can you explain what's going on more precisely?
The gain design of Sp400 and Sp200 is different, it is difficult to compare this volume in the case of high gain because it is a different gain.
 

leben

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The gain design of Sp400 and Sp200 is different, it is difficult to compare this volume in the case of high gain because it is a different gain.
mate, you've seen the post. he clarified he used M400 and used XLR input/XLR output on both cases. what's going on here?
 

leben

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Don't complain unless you don't have enough level at max volume settings. 12 o'clock is merely 1/4th of level and 1/16th of max power. These better designed amplifier don't have excessive high gain so you can use the full range of the volume pot. Many high gain amplifiers clip at very low output power but you don't ever get to see it clipping you thought it would have much higher power where they don't. Sp200 was partially that.

ye this very case is that. I was planning to buy susvara as my endgame cans but the output power of sp400 seems not to meet the manufacturer's claim. "beTteR dESIgNed"? Why do ppl set the "high gain" mode at the first place?
 
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