As implied by its name, the Baby Amplifier is quite small, 18cm wide, 23cm deep, and 13cm high (7in x 9in x 5in), and weighs about 7kg (15 lbs). The Baby Amp is rated at 10 watts per channel with distortion listed as less than 1% at full rated power. More important than distortion ratings, the specifications claim the frequency response of the Baby Amplifier to be an astounding 6Hz to 80KHz at ±3dB (12Hz to 45KHz at ±0 dB) and a signal to noise ratio of -95dB. These specifications are achieved using a Class A, push-pull circuit with output tubes wired in pentode mode and using minimal, global negative feedback. Solid state diodes take care of power rectification. Nominal speaker impedance should be 8 ohms.
The back panel contains the RCA input pair, the IEC power connector, and four speaker binding posts. The upgraded, high-end Sophia Electric speaker binding posts on the sample were gold plated and covered with protective clear plastic. Such a design would make accidental shorting by improperly secured speaker cables far less likely. The standard binding posts are simpler, gold-plated units. The binding posts were laid out in a line with the positive posts in the middle flanked by the negative posts.
How Does It Sound?
The sound quality of the Baby Amplifier is at once clean and clear, with quick transient response and potent immediacy. It is more aggressive sounding than most SET amps, but without the harshness or added grit of most solid state offerings, especially those in the same price range. The Sophia Electric Baby amp has greater impact and slam to the sound combined with more power for increased dynamic range, again, compared to typical, flea-powered SET amps.
The rated frequency response is phenomenal, listed by Sophia Electric as 6Hz to 80KHz at ±3dB. No measurements were taken, but the Baby Amplifier delivered everything within the audible range with clarity and strength. The little Sophia has strong, deep bass within the limits of all suitable speaker systems tried. Highs were clean and crisp, with no trace of grit, harshness, or odd, sibilant artifacts. Too often with inexpensive amplifiers, bells and chimes aren't recognizable, they simply don't sound like what they are. This is not a problem with the Sophia Electric Baby Amp - bells, triangles, and other high-frequency tones are easily recognizable (provided the recording is of decent quality!). Mid-range is clear and smooth. I have owned this little amp for 2 years.