DRIVE UNITS BY MANUFACTURER:
SB15SFCR39-4
UK STOCK ITEM
The SB Acoustics SB15SFCR39-4 is a unique 5x8 inch 'racetrack' style midwoofer featuring a robust vented steel chassis and a hard paper cone. This 4 ohm drive unit has that lovely warm, fast paper cone sound with good bass weight. Ideal for tall slim cabinets. Fantastic value.
Also available in 8 ohms: SB15SFCR39-8.
A matching passive radiator is available: SB15SFCR39-0
Resonant frequency (fs) | 31.5 Hz | Nominal impedance (Zn) | 4 Ω |
Mechanical Q factor (Qms) | 7.9 |
DC resistance (Re) | 3.5 Ω |
Electrical Q factor (Qes) | 0.34 |
Max power handling | 80 W |
Total Q factor (Qts) | 0.33 |
Sensitivity (2.83V/1m) |
89.5dB |
Equivalent volume (Vas) | 47.8L | Chassis |
253 x 153mm |
Friendly technical support
40+ years in the trade
UK family run business
Excellent customer service
Quick dispatch
Been looking for a supplier of replacement drivers for some years.
Willy's HiFi had just the parts at a good price and they arrived in a couple of days.
Excellent service. Even a personal thank you hand written on the invoice.
A quick delivery and the tweeters are perfect on my mission 753 freedom speakers. Easy to fit . Highly recommend.
I’m no expert when it comes to speakers, but after some research (and a strong recommendation from ChatGPT), I went with the SB Acoustics SB65WBAC25-4 as a reference full-range speaker in this size range.
Having now tested them, I can confidently say they’re probably the best speakers I’ve ever owned. The clarity is outstanding—every detail comes through with incredible precision. The bass is surprisingly full and punchy for a speaker this size, and they handle power impressively well. For anyone looking for a high-performance compact full-range driver, these are hard to beat.
Item as described and arrived quickly - and did the job. However, I suggested that anyone replacing speaker foam makes sure they have a very large pair of sharp dressmaking scissors as it was not easy cutting to size without producing a ragged edge (which I managed to hide short of a close inspection)!