Before we get started, check out Apos Audio. They are a great up-and-coming distributor with a phenomenal-looking website and excellent customer service. They also offer free shipping, the lowest price guarantee, a 2-year warranty, and a 45-day return. I do receive a kickback if you purchase from Apos, so your support is much appreciated!
Who is this Amplifier for? How does it sound? How does it compare with other amps without the THX moniker?
All of these answers and more, comin’ up in this S.M.S.L SH-9 Headphone Amplifier Review!
Greetings Bass Head and Welcome aboard. Stuart Charles here, HomeStudioBasics.com helping YOU make sound decisions leading to a beautiful audio experience that will make you fall in love with music (NOT gear), all over again, so…
Don’t forget to leave me some love and subscribe! <3
Power Supply voltage/frequency: AC100-240V, 50-60Hz
Power consumption (EN60065): 24W
Power consumption in standby mode: <0.1W
Size: 187.5 x 154 x 40 (mm)
Packing size: 282 x 232 x 79 (mm)
THX AAA-888 Headphone Amplifier with THX AAA Technology
6 Watts into 16 Ohm, 3 Watts into 32 Ohm Headphones with lowest THD+N
0.1 Hz to 500 kHz (-3dB) Frequency Response
Ultra-Compact Design, Perfect for Desktop Systems
Balanced Stereo Headphone Output
Balanced Stereo Line Input
High Precision Resistors for Temperature Stability
Pop-less Design with High-Quality Relays
High precision and low noise 256 level relay volume control
2 Positions Switchable Gain Control
Fully Protected with DC, Over-Voltage, Over-Current, Short-Circuit and Thermal Protection on Headphone Amplifier
High-Efficiency Ultra-Low-Noise Power Supply
1.9 inch LCD display
Who is the SH-9 for?
Dubbed the Smissle (by me), this Desktop Amplifier with Bluetooth capability targets the audiophile snob with its balanced XLR headphone input and balanced XLR dual inputs on the back for use with a separate DAC.
You can also use the SH-9 single-ended (unbalanced) with its RCA inputs.
On the front, we’ve got an XLR input for your balanced cables, as well as a single-ended 6.35 mm (1/4″) jack for use with unbalanced connections.
The middle contains the interface, and on the right, there’s the volume potentiometer.
Hold the volume pot in to bring up the menu. It’s a short hold. A long hold turns the unit off. For me, this is a minor nitpick. Sometimes I end up turning the unit off by accident.
Here you can cycle through your input, gain, volume mode, brightness, etc.
To back out, hold the volume pot in again.
I like the minimalist design of the amp. There are large numbers indicating what volume I’m at, an RCA switch (indicating mode), and a gain switch. These are both indicators and are for reference only, they’re not actual switches that can be ticked.
On the back, there’s an AC power jack for the supplied cable, as well as the RCA inputs, and the Balanced XLR inputs.
Build-wise, it feels incredibly robust and solid in your hands, and it’s just about the perfect size for full-time desktop use.
THX is a way to certify amplifiers that perform at a high level – by reducing distortion to almost nothing while maintaining the cleanest signal possible.
In the case of the SH-9, those qualities ring true, but, does it sound any better than a FiiO K5 Pro; an Amp/DAC that does not utilize THX? I went back and forth extensively trying to discern any differences, and I couldn’t.
Both are very clean sounding, but the K5 Pro may be a tad warmer. This is likely due to its somewhat higher output impedance at 1.2 Ohm. The SH-9 is advertised as close to 0. What is Output Impedance?
The problem for me boils down to Total Harmonic Distortion numbers. We’re talking about a potential difference that comes down to fractions of a percentage.
The S.M.S.L advertises less than 0.00006% vs. 0.004% for the K5 Pro. Looks like a big difference at first glance, but in reality, isn’t when you’re actually listening to music.
I’m bringing this up because THX’s main claim to fame is low distortion and a clean signal.
The truth is that most Amplifiers nowadays already have super low THD – it’s already entirely minuscule if we’re being honest.
The words “THX Technology” stamped on the top of the SH-9 don’t make me want to buy it over any other amp, especially when I can pay less and achieve the same effect.
Even with that said, it can be beneficial to have one simply because of the balanced feature; something I plan to invest in for myself down the road.
I like the SH-9 and it feels like it’s priced accurately; something that I think is super important especially with regard to Amps & DACS.
If you are looking for a full-time desktop unit with the THX stamp of approval and balanced functionality, I think this one fits the bill quite nicely.
It doesn’t really stand out against any other Amplifiers I’ve tried, so do keep that in mind before purchase.
Stu is determined to help you make sound decisions, and strives to deliver the best and most in depth content on the internet! In his spare time, he likes to fish, paint, play guitar, pray, rap, make beats, take photos, record videos, graphic design, and more. His sense of humour, coupled with a knack for excellence and strict attention to detail are what allow him to stand out in an crowded industry.