JBL 4315 (1975)
A compact 4-way studio monitor, the smallest in JBL's professional line.
Overview
The JBL 4315 is a 4-way, 4-speaker bass reflex studio monitor introduced in 1975. It was the most compact model in JBL's Studio Monitor series. The mid-woofer gets its own enclosure to keep the drivers from interfering with each other. The front panel has level controls for mid-low, mid-high, and high frequencies. It came in gray or walnut. JBL marketed it for professional and high-end consumer use and issued a brochure in 1974, ahead of the release.
Specifications
| Playback frequency band | 35 Hz to 20 kHz ± 3 dB |
| Crossover frequency | 400 Hz, 2 kHz, 8 kHz |
| Impedance | 8 Ω |
| Output sound pressure level | 89 db (New JIS) |
| Allowable input | 60W (continuous program) |
| Enclosure volume | 73.8 liters |
| Mid-Woofer enclosure volume | 2.8L |
| External dimensions | Width 520x Height 850x Depth 280 mm |
| Weight | 41kg |
| Unit Low Band | 30 cm Cone Type (2203A) |
| For Medium Low Band | 20 cm Cone Type (2108) |
| For Middle and High Areas | 13 cm Cone Type (2105) |
| For High Pass | Horn Type (2405) |
Design
The 4315 is a bass reflex design with an internal mid-woofer chamber, which keeps interference between the drivers down. Front-panel level controls cover the mid-low, mid-high, and high-frequency sections, so you can fine-tune the sound. It is a 4-way, 4-speaker system in a bookshelf-type form factor, offered in gray or walnut.
Context
JBL built the 4315 as the smallest model in its Studio Monitor lineup. It was positioned for professional monitoring and high-fidelity home use. The product brochure came out in 1974, and the speaker reached the market in 1975.
Market
A 1994 classified ad listed a pair of JBL 4315 speakers in walnut/BO finish for $750. That puts them on the secondhand market over a decade after release.
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