In this blog post I test a brand new TAD TD-2002 1" compression driver. The driver is a top tier unit which retails for $3,295.00 USD each! (Pro Audio Design.com)
Introduction to the TAD TD‑2002 Compression Driver
Historical Context
The TAD TD‑2002 is a compact yet sophisticated compression driver designed by Pioneer’s Technical Audio Devices (TAD) brand—a high-end pro‑audio division originally established in 1979 and widely adopted in recording studios worldwide (Pioneer Global). Launched in April 1997, the TD‑2002 entered the market alongside its sibling, the TD‑4003, as part of TAD’s “Exclusive” professional speaker lineup (Pioneer Global).
Design & Construction Highlights
Diaphragm & Material Science
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The TD‑2002 features a 4.8 cm (roughly 2‑inch) beryllium diaphragm, produced using a precision vacuum‑deposition technique—this renders it both extremely lightweight and impressively rigid. The result: resonances pushed well beyond the audible band, enabling a flatter frequency response, enhanced resolution, and superior transient performance (Audio Database, Pioneer Global).
Magnetic Circuit & Motor
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Powering the diaphragm is an Alnico 5 magnet, coupled with an internal geometry (pure iron poles, top plates, ductile‑iron yokes) that yields high linearity and broad bandwidth reproduction. This setup achieves a magnetic flux density of 1.95 T and a total flux of around 7.42 × 10⁻⁴ Wb (Audio Database, Technical Audio Devices, Pioneer Global).
Phasing Plug & Direct Power Coupling
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The driver employs a rear‑type, three‑slit phasing plug that is precisely shaped to maintain phase integrity across a wide frequency range—delivering a clean and well‑defined high‑frequency response (Audio Database, Pioneer Global).
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Additionally, it incorporates Direct Power Coupling technology, enabling direct wiring from the input terminals to the diaphragm. This minimizes unwanted resonances from AC interference and enhances clarity (Technical Audio Devices, Professional Audio Design, Inc).
Technical Specifications
| Specification | Value |
|---|---|
| Impedance | 8 Ω |
| Frequency Range | 800 Hz – 20 kHz |
| Sensitivity | 111 dB SPL (1 W @ 1 m) |
| Rated / Max Input Power | 10 W / 40 W |
| Crossover Frequency | ≥ 800 Hz (recommended) |
| Voice Coil Diameter | 48 mm |
| Throat Size (Hole Diameter) | 25.4 mm (1") |
| Mounting Options | 57.2 mm (3-holes), 76.2 mm (4-holes) |
| Dimensions | 141 mm × 137 mm (dia × depth) |
| Weight | ~6.9 kg |
| Diaphragm Repair Part | SXV‑1005 |
| (Audio Database, Professional Audio Design, Inc) |
Custom Horn No.2994
I decided to design a custom horn dedicated to the TAD TD-2001/2 because of the narrow driver exit angle unique to these drivers. The driver uses a 3.5° half angle (7.0° included).
Horn No.2994 is a modified version of the ES-600 Biradial Horn No.1978. The exit angle for the standard ES-600 Biradial (No.1978) is 10° half angle (20° included). The throat is also reduced from 1.40" diameter to 1.00".
In order to maintain the mathematical ES curvature, the physical width of the horn had to be reduced from 416mm to 345mm.
Measurements
Frequency Response and Impedance
1/24 dB Smoothed response Gated, spliced at 2kHz (ungated and smoothed below 2kHz)
Raw DFT unsmoothed response (Gated 2.38ms)
Horizontal Off-Axis Polar Map 20kHz Contoured, 1/12 smoothing
Time Domain
Burst Decay (25dB vertical scale)
Burst Decay (35dB vertical scale)
Spectral Decay (25 dB vertical scale)
Spectral Decay (35 dB vertical scale)
Distortion
SMPTE IMD using F1 1kHz F2 10kHz (4:1 power ratio), resulting in 1.15% total IMD for 85dB test signal measured at 1m. H2 and H3 are equal, IMD1 at -42dB. (referenced from F2)
Same as above except 95dB test signal. SMPTE raises to 3.08%, IMD1 at -32dB.
Conclusion
The TAD TD‑2002 is a meticulously engineered, 1‑inch compression driver that combines a beryllium diaphragm, high‑flux Alnico motor, precision phasing plug, and Direct Power Coupling—resulting in superb clarity, high sensitivity, and reliable durability. Whether used in pro‑audio monitoring or audiophile DIY systems, it remains a benchmark for performance.