This is a review and detailed measurements of the SMSL SH-8S. It was kindly drop shipped to me from SMSL by ShenzhenAudio. Unfortunately I do not have price or availability. As soon as I find out, I will update the review.

I don't know how many colors the SH-8S comes in. The silver one looks fine but made it hard to read the labels:

As you will see later in the measurements, the XLR output is for convenience and does not produce more power. There are balanced inputs however which I like:

Inclusion of mains power supply is a nice touch as it eliminates desk clutter.

Good to see regulatory certification on the back.

Note that you only have low and high gains. No medium.

SMSL SH-8S Measurements
I configured my unit with XLR input and tested with both 1/4 and XLR outputs. Results were identical. Here is the XLR one:

This is exceptional performance and lands the SH-8S at the top of the chart with its competitors:

This is one quiet unit with superb dynamic range:

As such it should very much be suitable to ultra sensitive IEMs.

Frequency response is ruler flat well beyond what we need for audio:

Performance as stated is exceptional in low gain mode but high gives up a bit of that:

Still, plenty of power available at 300 ohm. To show that there is no difference between output headphone jacks, here is the comparison:

Low gain remains excellent at 32 ohm but high gain slides a bit more competitively:

There is essentially no load dependency other than drop in output voltage as impedance get lower:

Channel balance is excellent for an analog volume control but the unit you buy may be very different:

SMSL SH-8S Headphone Listening Tests
I will make this short: with both my Sennheiser HD-650 and Ether CX headphone, there was a ton of power available even in low gain mode. High gain had ample headroom well beyond what I would dare to play. There was no distortion I could attribute to the amplifier. Excellent performance all around.

Conclusions
We had a DAC race start a couple of years ago to get perfection. We are now well into headphone amplifier perfection gain, with one instrument grade amplifier after another. Each has a different form factor, pricing, and availability though so having options is good. Such is the story of SH-8S. Superb measured and subjective performance.

It is my pleasure to put the SMSL SH-8S on my recommended list.

Note: this is a brand new product. Some headphone amps have had teething issues when released. If you are worried about such things, let others go before you and get some data on reliability.

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