Overview

The Coral Beta-10 is a 25cm (10-inch) double cone full-range speaker driver manufactured by Coral Audio Corporation of Japan between 1970-1985. Part of the Beta series, it features a unique skybar edge and star-shaped diffuser with ALNICO magnet technology. Despite its legendary status among vintage audio enthusiasts, the Beta-10 suffers from significant technical limitations including a severe 2.1kHz resonance peak. Coral Audio Corporation went bankrupt in the mid-1980s, making this a discontinued vintage product with no manufacturer support.

Scientific Validity

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The Beta-10 demonstrates problematic measured performance that falls well below modern transparency standards. Frequency response spans 32Hz-20kHz with official sensitivity rated at 97dB, though user measurements show variation (94.96dB in one example) [2][6]. The driver includes a documented severe resonance at 2.1kHz requiring notch filtering [1]. Measured Thiele/Small parameters from user testing show Fs: 37.01Hz, Qts: 0.496 [2]. No published THD, SNR, or IMD measurements are available from third-party sources. The significant mid-frequency resonance issue places this driver at the problematic level according to measurement criteria, requiring active filtering to achieve acceptable linearity.

Technology Level

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The Beta-10 represents solid 1970s engineering with some innovative features for its era. The double cone design with bullet center cap enabled full-range operation, while Coral’s proprietary skybar edge and star-shaped diffuser expanded directivity [3]. The diaphragm uses pulp mixed with chemical fibers to reduce density variations, and the voice coil employs copper-coated aluminum wire combining material advantages. However, this represents purely analog/mechanical technology from 50 years ago without modern digital integration or contemporary materials science advancements.

Cost-Performance

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Current market pricing for the Beta-10 ranges from 275-4,200 USD with typical good condition pairs around 1,200 USD. The Tang Band W8-1772 offers equivalent-or-better performance with 97dB sensitivity, 42Hz-20kHz response, 60W power handling, and modern neodymium magnets at approximately 400 USD per pair [4]. Equipped with comparable full-range functionality, the W8-1772’s frequency response and power handling are equivalent-or-better without documented resonance issues. CP = 400 USD ÷ 1,200 USD = 0.33.

Reliability & Support

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As a vintage product from Coral Audio Corporation (bankrupt since mid-1980s), no manufacturer warranty or official support exists. Repair services are limited to third-party vintage audio specialists with typical 2-3 week turnaround times and 60-day guarantees [5]. Replacement parts availability is extremely limited due to the discontinued status and company closure. While the simple mechanical design provides inherent durability, aging components and lack of manufacturer backing create significant reliability concerns for practical use.

Rationality of Design Philosophy

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The Beta-10 represents 1970s analog design philosophy emphasizing subjective sound qualities over measurable performance metrics. While the white diaphragm was specifically chosen “to avoid coloring” and demonstrated attention to acoustic principles, the design lacks scientific measurement-based optimization [6]. The approach was innovative for its timeframe but conflicts with modern transparency-focused methodologies. The severe 2.1kHz resonance indicates design compromises that prioritize other factors over flat frequency response.

Advice

The Coral Beta-10 should be avoided for serious audio applications due to fundamental technical limitations and poor cost-performance. The documented 2.1kHz resonance requires additional filtering components, negating the simplicity advantage of full-range designs. Modern alternatives like the Tang Band W8-1772 provide superior performance at significantly lower cost without vintage reliability concerns. Only consider if specifically seeking a vintage collector’s item for historical interest rather than optimal audio reproduction.

References

1. hifi-selbstbau.de, Coral Beta 10B, https://hifi-selbstbau.de/index.php/hsb-datenblaetter/historische-chassis/coral-beta-10b, accessed 2025-09-04
2. diyAudio, cab options for coral beta 10, https://www.diyaudio.com/community/threads/cab-options-for-coral-beta-10.340441/, accessed 2025-09-04
3. hifi-wiki.com, Coral Beta-10, https://hifi-wiki.com/index.php/Coral_Beta-10, accessed 2025-09-04
4. Parts Express, Tang Band W8-1772 8” Neodymium Full Range Driver, https://www.parts-express.com/Tang-Band-W8-1772-8-Neodymium-Full-Range-Driver-264-893, accessed 2025-09-04
5. dBm Pro Audio, Pro Audio Repair Equipment, https://www.dbmproaudio.com/, accessed 2025-09-04
6. audio-database.com, CORAL BETA-10 specifications, https://audio-database.com/CORAL/unit/beta-10.html, accessed 2025-09-04

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