In the first part of the review, I wrote that the RSA Shadow really sounded great out of the box. However, the designer, Ray Samuels, wrote on the manual that 100 hours of burn in is required of the Shadow. I didn’t want to argue the man, so I decided to put it through some burn in, constantly monitoring if there are any changes in the sound.
During the burn in period, I kept on wondering when the battery will run out. Fully charged, it was able to run for three days straight. Ray did write that the Shadow can last up to 72 hours of play using IEMs, but my 72 hours was done using the Shure SRH-840 full size headphone, at a moderately high volume level. Very impressive indeed.
After 200 hours of burn in, the only change I noticed was that the sound got smoother roughly after the first 24 hours. I honestly don’t see anything that needs to be changed, as it was already great out of the box.
In my initial impression of the Shadow, I wrote that the amp sounds great without any obvious coloration. The presence of capacitors, no matter how boutique your capacitors are, will add color to the sound. Ray claimed that his design is the only one with no input or output capacitor in the signal path — hence the neutrality of the Shadow. Another thing that impressed me was the instrument separation. Ray Samuels explained that left to right channel balance is critical to proper positioning and staging and I have to agree with him. I compared the Shadow and the Corda 3Move again today, and my impression still stands. The Corda 3Move is a very good performing amp, but compared to the newer generation of digital volume controls and stepped attenuator equipped portables, I am not sure if the older analog-pot amps can still compete.
With the digital volume control of the Shadow, not only do you get great instrument separation, but the annoying channel imbalance at lower volumes become a thing of the past. From dead quiet, the volume smoothly increase without any imbalances or any obvious jumps in volume level. The volume control on the Shadow is a joy to use. Being accustomed to knobs for volume control, I did find the volume toggle lever unnatural to use at first. However, after one week with the Shadow, I’m now loving the toggle mechanism!
The Shadow has a superb build quality that is typical of Ray Samuel amps. Even at a minuscule size, the volume lever, the LEDs, in/out and USB jacks, and the on-off switch all are precisely aligned to the casing. I also love the small details that Ray designed into the amp, such as the on/off switch that doubles as an on/off led indicator. Please don’t mistake the USB connector at the back as an input for a DAC, as the Shadow doesn’t have a DAC. The USB is used for charging the Shadow from a USB port or from the supplied charger.
As the quality of IEMs get better by the day (JH13Pro, and now the upcoming JH16), more and more people are using IEMs for their portable gear. Ray Samuels obviously see this trend and he designed the RSA Shadow mainly as an IEM amplifier. We all know that most IEMs sound good straight out of a DAP. But I’d still want to use an amp, to add that little juice that makes your IEM from sounding good to great. The Shadow has a fixed gain of three. Its perfect for an IEM, but it still has enough gain for driving a full-size like the Shure SRH-840 (44 Ohms) and the Sennheiser HD25-1 (75 Ohms).
The closest portable amplifiers that compete with the Shadow in terms of size is the Fiio E5, the Ibasso T4, and Ray’s own P-51 Mustang. The Fiio E5 is a few leagues behind so I won’t talk about it. The Ibasso T4 is a great small amp for under $100, but compared to the Shadow, it’s still inferior, both in sound and build quality. Ray’s own P-51 Mustang may be the Shadow’s closest competitor, and I will write an update article comparing the Shadow to the P-51.
Of course when you go to a bigger sized amp like the 3Move or the TTVJ Stepped Attenuator, you get a much fuller sound and a bigger punch than you do with the Shadow. There is no comparison. The point in the Shadow, however, is real world portability. Where carrying an Ipod Classic with a regular sized amp feels like having a small brick in your pocket, the Shadow with an Ipod Nano feels very light on your pocket, roughly the weight of a Blackberry smartphone. If you don’t see the need to get a line out signal from your DAP, you can go even smaller with a Sansa Clip+. Then, you can either hook up an IEM and have a fairly “invisible” killer portable, or walk around with a small closed cans like the HD25-1 and still enjoy great sounding music. In the old days, a small set up like this means compromised music. Not more today. The RSA Shadow truly marks a new generation of portable amps. Great sound out without the hassle and the weight of past amps.