Short answer: the Audioengine A2+. It ranks #19 of 48 powered bookshelf speakers by sound quality (rated 3.4/5) at $299 and is still sold new; the Monacor SOUND-4BT ranks #22 (rated 3.3/5) and is discontinued, so it is only an option used.
The Monacor SOUND-4BT is the more accurate pick. A compact powered pair with Bluetooth, optical and analog inputs, a remote and a subwoofer output. Its measured preference score, a predictor of how neutral it sounds, is 3.58 against 2.78 for the Audioengine A2+. Watch for: Predicted in-room response remains uneven despite the modest midrange span.
Why pick the Audioengine A2+: Tiny desktop speakers with Bluetooth, USB and analog inputs and a variable RCA output. The catch: The 2.78 standalone score and roughly 106Hz measured -3dB point reveal how much bass is missing without reinforcement or a subwoofer.
Buy the Audioengine A2+. It is rated higher for sound quality, and the Monacor SOUND-4BT is discontinued, so it is only available used.
Looking for alternatives? See the complete Powered Home rankings.
A compact powered pair with Bluetooth, optical and analog inputs, a remote and a subwoofer output.
Tiny desktop speakers with Bluetooth, USB and analog inputs and a variable RCA output.
Prices on this page were last checked October 23, 2026 at 8:27 AM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.
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Specifications Side By Side
| Monacor SOUND-4BT | Audioengine A2+ | |
|---|---|---|
| Price | $310 per pair Discontinued | $299.00 per pair |
| Ranked | #22 of 48 in Small Size Powered Bookshelf Speakers | #19 of 48 in Small Size Powered Bookshelf Speakers |
| Enclosure | 2-way powered stereo pair, bass reflex | - |
| Drivers | 1” dome tweeter, 4” woofer | 0.75” silk dome tweeter, 2.75” fiber woofer |
| Dimensions | 8.5H x 5.5W x 6.7D in | 6” x 4” x 5.2” (152 x 102 x 133 mm) |
| Weight | 11.5 lbs (5.2 kg)/pair | 3.5 lbs (1.6 kg) left / 3.1 lbs (1.4 kg) right |
| Amplifier Power | 2 x 30W RMS | 15W RMS / 30W peak per channel |
| Inputs | Bluetooth 4.0 aptX, optical, RCA, 3.5mm | RCA, 3.5mm, USB, Bluetooth 5.0 |
| Bluetooth Codecs | SBC, aptX | - |
| Spinorama Preference Score | 3.58 | 2.78 |
| Spinorama Preference Score with Perfect Sub | 6.10 | 6.10 |
| Subwoofer Output | Yes | Yes |
| Outputs | Subwoofer | RCA variable output (subwoofer) |
| XLR Input | No | No |
| RCA Input | Yes | Yes |
| TRS Input | No | No |
| Optical Input | Yes | No |
| Coaxial Input | No | No |
| USB Input | No | Yes |
| HDMI Input | No | No |
| AES Input | No | No |
| Aux Input | Yes | Yes |
| Bluetooth | Yes | Yes |
| Bluetooth Version | 4.0 | 5.0 |
| Frequency Response | 45Hz - 20kHz (Manufacturer specified) | 65Hz - 22kHz (+-2dB, Manufacturer specified) |
| Bass Extension (-3dB) | - | 105.5Hz (measured, Erin’s Audio Corner) |
| Bass Extension (-10dB) | - | 58.9Hz (measured, Erin’s Audio Corner) |
| EQ | - | No (fixed volume knob only) |
| App | - | No |
Frequency Response Compared
Both speakers’ spinorama measurements, overlaid. A flatter line is more neutral: peaks sound forward or harsh, dips sound recessed. Each curve is shifted so its average from 300 Hz to 3 kHz sits at 0 dB, so loudness differences between the two are removed and only the shape is compared. The two were measured by different sources, so small differences, especially in the bass, can come from the measurement setup rather than the speakers.
Measurement data: Monacor SOUND-4BT (measured by an independent reviewer) and Audioengine A2+ (measured by Erin’s Audio Corner), via spinorama.org.
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