The Optimal Audio Cuboid 10 ranks #3 out of 32 total Surface-Mount and Background Music Speakers for sound quality. See all PA & Live Sound rankings for every top pick.
Brand: Optimal Audio
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#3 Optimal Audio Cuboid 10: $660 each Passive eBay
Pros: A larger member of Optimal Audio’s Cuboid installation range, with a 10-inch woofer that reaches 47.5Hz at -3dB in vendor measurements, deep for an installation box, and a cabinet matching the smaller Optimal Audio Cuboid 5. Measured bass extension of 37.6Hz (-10dB).
Cons: Directivity is uneven (3.93dB variation) and the on-axis response is uneven (0.61 band deviation), so it scores 3.01 on its own and 5.08 with an ideal subwoofer. It is sold through Allen & Heath and Optimal Audio installers with no US retail listing.
| Bass Extension (-10dB) | about 37.6Hz (derived, log-interpolated between spinorama.org -9dB/-12dB points) |
|---|---|
| Bass Extension (-3dB) | 47.5Hz (measured, manufacturer data via spinorama.org) |
| Bluetooth | No |
| DIY Kit | No |
| Drivers | 10” woofer, 2-way |
| Passive | Yes |
| Spinorama Preference Score | 3.01 (spinorama.org) |
| Spinorama Preference Score with Perfect Sub | 5.08 (spinorama.org) |
- Reviews, Comparisons and Sound Samples
Frequency Response
How the Optimal Audio Cuboid 10 measures across the audible range. A flatter listening window (the sound arriving straight at you) is more neutral: peaks sound forward or harsh, dips sound recessed. The estimated in-room response adds what a typical room does, and there a gentle, even tilt down toward the treble is ideal. Both curves are shifted so their 300 Hz to 3 kHz average sits at 0 dB.
Measurement data: spinorama.org, measured by the manufacturer.
EQ for a Neutral Response
Flattens the measured listening window from the Optimal Audio Cuboid 10's own bass extension up to 16 kHz. Set a preamp of -2.6 dB, then add these filters to any parametric equalizer in the signal path: the speaker's app or DSP if it has parametric EQ, a miniDSP, Equalizer APO or Wavelet. Boosts are kept to 3 dB, and EQ cannot fix how evenly the speaker spreads sound off-axis, which is why some speakers gain more than others. Predicted preference score with this EQ: 4.0, up from 3.0 (6.2 with an ideal subwoofer, up from 5.1). Calculated by Speaker Ranking from the spinorama measurements above.
| Filter | Frequency | Gain | Q |
|---|---|---|---|
| High shelf | 8,000 Hz | -1.4 dB | 0.70 |
| Peak | 87 Hz | -4.8 dB | 0.82 |
| Peak | 260 Hz | -1.6 dB | 2.19 |
| Peak | 989 Hz | +1.6 dB | 4.00 |
| Peak | 2,991 Hz | +2.8 dB | 4.00 |
| Peak | 5,712 Hz | -2.8 dB | 2.08 |