“This Thing Is Truly Legit”: Home Theater Hobbyist on the SMSL SA400

Note: This article is based on the video "Raw POWER!! S.M.S.L SA400 Stereo Speaker Amplifier Review" made by Cody of Home Theater Hobbyist on his YouTube channel and is printed here in partnership with Cody of Home Theater Hobbyist. The review was originally posted on October 3rd, 2022. Edits have been made for clarity and length. You can purchase the SMSL SA400 Stereo Amplifier on Apos Audio


What’s going on, everybody? This is Cody, the Home Theater Hobbyist. A few months ago, I had the opportunity to review a nice little two-channel amplifier called the SMSL DA9. I liked it a lot because it was nice and compact and had a nice, clean sound to it, and it could power most speakers. It was sent to me by Apos Audio. When I returned it to them, I told them that I liked it, and they said, “Hey, Cody, if you really like that one, you’ll love this one,” and they sent me the SMSL SA400.

This is larger than the DA9. It has a few more features, and it has a lot more power–I’m talking Tim the Tool Man Taylor-type power. This thing is truly legit. 


If you want high-res audio, you’re going to need a DAC. The SA400 does have Bluetooth, but it only supports aptX, which sounds good, but aptXHD and LDAC are going to sound better. If you’re purchasing this, honestly, you probably need to be using it for high-res music. 


Now, one of the questions that I wanted to answer with the SA400 is does it have enough power to drive a difficult-to-drive speaker at reasonable volume levels?

I wanted to test this at reasonable volume levels, so I set my sound meter at my main listening position, and I was targeting 75dB. I set the preamp volume at 100, then I began increasing the volume on the SA400 while using the Klipsch RP150M speakers. I found that at a volume of 22 on the SA400, I got 75dB at the listening position.

Now, when I listened to the Arendal Sound 1723s speakers, the volume had to increase to 30 out of a total of 80. So it had plenty of headroom.

If I listened on an 84dB efficient speaker set, I would probably have had to turn it up to 45, maybe 50. But again, I would still have had headroom, and that’s what you’re looking for.

Next, I wanted to turn the preamp volume down just a little bit, so I set it to 75, which caused me to turn the SA400 volume output to 60 for the 1723s. So you still have some headroom there, but not a ton. Somewhere between 70 and 100 preamp volume is the sweet spot.

But again, you have headroom with this amplifier. It can drive every speaker known to man. Okay, probably not, but it’s going to be able to drive a ton of them because it has headroom. 

Sound quality

This has the SMSL sound. What I mean is that it’s got a nice, clean, clear sound at pretty much all frequency ranges. And it’s kind of a direct sound. So you get nice treble, you get a nice natural mid-range, and you get tight, clean bass. It really reproduces what the artist intended.

Now, for the bulk of my testing I listened to this in the default EQ mode, which is called “Direct,” but it has several others. In that Direct EQ mode, I listened to a gospel artist named Brian Popin, who has this song that starts off with somebody singing into what sounds like a transistor radio, because it’s small and there’s these hisses and pops going on.

The SMSL SA400 played that very very well. I mean, I felt like I was listening to a transistor radio. But then the song transitions into a stage  with a band and a full choir. The sound stage really opens up quite big, and the SA400 captured that sound as well.

All of a sudden, the sound stage just opens up and you’ve got this big band playing, and this choir singing. It works realy well, But what I was really intrigued by was the transition from, let’s say, transistor sound to that big sound. It was a nice, smooth transition, as I imagine the artist intended.

I also listened to an artist that I actually just became familiar with. It’s an album called “Reach” by a jazz pianist called Jackie Harrison. This is a well-recorded album. What I like about this particular album is that, honestly, it sounds like it’s recorded in a small bedroom, because it’s a real kind of closed inside sound.

It’s clean, but it’s really closed-in sounding. Again, this played that sound without any issue whatsoever. That’s what you want from your amplifier.

I also noticed that it doesn’t seem to color the sound at all in that direct EQ mode. I compared this to my Monoprice Monolith 7-channel amplifier, and I didn’t notice any additional color. I also compared it to the Emotiva BasX A7 in two-channel mode. Again, I did not hear any additional coloration. I did notice that this does have a bit more power than that does in two-channel mode. 


This costs $660, and I think that’s actually a pretty good price. You can definitely find two-channel amplifiers that are way more expensive than this, but they may not even sound as good, plus this has a ton of nice features like EQ modes and auto-off.

So this is actually a really good deal, and I do recommend it.