Сабвуферы — Pro-Ject Sub Box 50 E

The Sub Box 50 E is a compact active subwoofer from Pro-Ject, the Vienna-based maker of turntables and compact hi-fi electronics. It uses a sealed cabinet with a down-firing driver and is priced at EUR 299 including VAT according to the maker's 2024 data sheet. A version without the E suffix, the Sub Box 50, also exists in the range.

Key specs that matter

The driver is a 130 mm woofer facing the floor. The built-in amplifier delivers 50 W RMS, with a peak rating of 100 W, and has a signal to noise ratio of 72 dB and THD+N of 0.015% at 1 W. Frequency response runs from 38 Hz to 160 Hz at -3 dB. The crossover can be set continuously between 65 Hz and 150 Hz, and a switch inverts the phase. Inputs are stereo or mono RCA at line level with 140 mV sensitivity, and stereo or mono speaker-level terminals with 3.5 V sensitivity. Power draw is 0.4 W in standby, 10 W with no signal and 101 W at full output. The cabinet measures 205 x 280 x 205 mm, weighs 6 kg and comes in high-gloss black or white.

Engineering and use context

A sealed enclosure has no port, so the woofer works against the trapped air inside the box, which acts as a spring and controls cone movement. The cabinet is made from non-resonating MDF, and a metal back plate carries the amplifier and controls. With the driver facing the floor, the cone stays out of sight and the floor reinforces its output, and the small square footprint fits under a desk or beside a sideboard. The variable crossover lets the subwoofer take over below the natural limit of the main speakers, whether they are small satellites that roll off high or larger bookshelf models that reach lower. The phase switch aligns the output of the subwoofer with that of the main speakers when the two are placed at different distances from the listener. Two power modes are provided. In always-on mode the amplifier stays active, while in auto-on mode it switches on when a signal arrives and returns to standby after 10 minutes without one. The high-level terminals accept speaker cable directly from an amplifier's outputs, which allows the subwoofer to be added to systems whose amplifiers have no dedicated subwoofer output.

Pairing

The RCA input connects to the subwoofer output of Pro-Ject Box Design amplifiers and to any preamplifier or receiver with a line-level output. With amplifiers that lack such an output, the speaker-level input takes the signal in parallel with the main speakers. It suits desktop systems and rooms of up to about 20 m2.

Alternatives

The Pro-Ject Sub Box 200 is a larger subwoofer from the same Box Design range.