DRIVE UNITS BY MANUFACTURER:
C158-8-085

The Accuton C158-8-085 Bass / Midrange driver is a development of the C158-6-851 with a slightly different design criteria : a revised motor system comprising of a light weight 25mm voice coil and titanium former assembly give improvements to both midrange resolution and extension plus a mild increase in sensitivity.
Designed specifically for small monitors and slim floor standing designs, this esoteric unit has a soft rubber suspension, an ultra hard 120mm ceramic (Sapphire) cone and a large 10mm maximum excursion allowing it to produce impressive volume levels from small footprint enclosures.
The spider, pole and voice coil former are fully ventilated for minimal compression. This 8 ohm unit has a power rating of 100 watts - very respectable for a domestic driver of this size.
Full datasheets can be downloaded from the bottom of this page.
Vented:
Vb: 15L, Port diameter: 50mm, Length: 190mm, Fres: 41Hz, F-3dB: 45Hz, Q: 0.58
Vb: 22L, Port diameter: 50mm, Length: 130mm, Fres: 40Hz, F-3dB: 40Hz, Q: 0.50
Vb: 12L, Port diameter: 50mm, Length: 200mm, Fres: 45Hz, F-3dB: 49Hz, Q: 0.61
Infinite baffle:
Vb: 8.5L, -11dB @ 40Hz, F-3dB: 70Hz, Q: 0.71
Vb: 22L, -8.5dB @ 40Hz, F-3dB: 70Hz, Q: 0.50
| Resonant frequency (fs) | 33Hz | DC resistance (Re) | 7.8Ω |
| Mechanical Q factor (Qms) | 4.12 | Power handling | 100W |
| Electrical Q factor (Qes) | 0.34 | Sensitivity (2.83V/1m) | 89dB |
| Total Q factor (Qts) | 0.31 | Chassis diameter | 158mm |
| Equivalent volume (Vas) | 35L | Cutout diameter | 137mm |
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