Before I begin my long tale about my listening to the KamaBay Amp and measuring its characteristics, I want to tell you first what you should not do with this amplifier. When I took the device out of its box I really wanted to install it into a 5-inch bay of my system case and forget about the included power adapter. But I soon had to give up that idea. When the computer had booted Windows up, I bravely pressed the Power button on the amplifier and the whole computer just shut down instantly. A sudden surge in the current consumed for loading the amplifier’s capacitors triggered protection in my Rosewill Turbo Series RT550-135-BK, which is quite a sturdy 550W power supply. Of course, there are no problems if you turn the amplifier on beforehand, but I don’t think it reasonable to risk shutting down your computer by pressing a single button. Therefore I used the amplifier only with its external power adapter. Moreover, when the amplifier was connected to the PC’s power supply, there was too much extra noise in the headphones among which I could easily identify the moments of activity of my hard drives and other devices populating my system case.
So I began my tests by listening to the amplifier in headphones. Like in my previous reviews, I used Grado SR 325i headphones and a C.E.C. HD53R-80 amplifier. This amplifier is a good choice for making a comparison with the KamaBay Amp because it allows connecting both headphones and speakers, too. Of course, these two devices come from different categories, the KamaBay being more than 10 times cheaper, yet it is better to compare sound quality with an etalon, and the C.E.C. amplifier can serve as such well enough. The sound source was an ASUS Xonar D2 sound card that had proved its overall superiority over the Creative X-Fi Elite Pro and Auzen X-Fi Prelude 7.1 in our comparative tests. I used various test materials that had one common property: every recording was ripped from a CD and saved either in uncompressed WAV format or in compressed lossless format (Monkey’s Audio). I reproduced them with foobar2000 version 0.9 with 24-bit precision Kernel Streaming output.
Quite expectedly, the Scythe KamaBay Amp lost the first round of the comparison. It was considerably inferior to the more expensive opponent (from amplification class A). The most notable difference was that it reproduced dry and muddy high frequencies, resembling the notorious “digital” sound compact-discs had been criticized for. I could also note it to have a worse attack, less rich timbres of vocals and instruments. It lacked the minor details of live recordings that created the effect of your being present in the concert hall. This can be characterized as the reduction of transparency and resolution. The sound stage is flat and the sound is unexciting overall. Connecting the headphones directly to the line output of the sound card (which has an additional buffer with dual general-purpose opamps) proved to be preferable. I even could not decide what sound I liked better: with the C.E.C. amplifier or without any amplifier at all.
After making a number of comparisons using various kinds of audio materials, I found out that when the headphones were connected to the ASUS Xonar D2’s line output, I could hear more of smaller details and the sound was livelier overall, but the sound card would lose its ground on intensive passages, not coping with the reproduction of all the nuances of the performance. The C.E.C. showed its best where maximum dynamics was needed. It maintained the purity of timbres and excellent resolution in any situation. With powerful bass and delicate drive, the C.E.C. did especially well with classic musical compositions. For example, the ASUS Xonar D2 would occasionally produce slack and clamorous sound even in calm places (those without much polyphony) of Rimsky-Korsakov’s Scheherazade.
The KamaBay Amp should be given credit for passing the Scheherazade test successfully. I was quite carried away with the composition when listening to it via that amplifier. The difference from the C.E.C. amplifier was in the lack of the concert hall feeling, poor echeloning, unexpressive medium frequencies and muddy high ones (like in the ringing of the triangle). This impaired my experience from the suite somewhat, but it was even less fun to listen to it without the amplifier.