SilverStone EB03 Amplifier Specifications
When comparing the merits of different headphone amplifiers, it is common practice to look at the audio specifications of the competing devices and draw conclusions based on the published performance of the amplifiers.
SilverStone has done something interesting with the audio specifications for the EB03 headphone amplifier; they have not provided any. Instead, they list the audio ICs used in the design of the amplifier, and leave it to the user to further research the performance of those ICs.
This is an interesting approach, as it provides the technically inclined customer enough information to determine the expected performance of the headphone amplifier. On the other hand, it does not provide the customer with a guarantee of minimum audio quality for the EB03 amplifier design, but rather implies that the amplifier will have performance typical of the design recommended by the IC manufacturer.
The SilverStone EB03 uses the 1646W16-U and 1512S14-U audio ICs from THAT Corporation. THAT is a US headquartered company that has been designing professional audio components for about 25 years. The company was formed by engineers and managers from dbx Inc., whose noise reduction technology has been used in professional audio for decades.
Frequency Response and Noise
The EB03 design consists of two channels of the THAT 1512 preamplifier and 1646 audio driver ICs. Specifications provided in the datasheet for these components predict that:
- The EB03 amplifier should have a flat frequency response out past 20 kHz.
- The total amount of harmonic distortion at high listening volume should be less than 0.005 % or about 86 dB below the signal.
- The noise added by the amplifier should be difficult to measure without specialized measuring equipment.
Essentially, this amplifier should have a flat audio frequency response and should not introduce any noise or distortion that can be perceived by the casual listener.
The typical output impedance of the THAT audio driver is 50 ohms.
Headphone amplifier output impedance can be a confusing topic. Headphones range in impedance from less than 32 ohms to over 600 ohms. A good headphone amplifier should be capable of providing enough current to drive a low impedance headphone while being able to provide enough voltage to drive a high impedance headphone to a satisfactory listening level.