Triangle Antal 40th Anniversary Loudspeaker Lab Report

Lab Report

Rated at a high 92dB sensitivity, the 40th Anniversary edition of Triangle's Antal floorstander achieves a not inconsiderable 89dB/1kHz and 90dB/500Hz-8kHz, the latter figure boosted by the resonant 'bumps' in its response [see Graph 1] where it's most uneven from 800Hz-5kHz. Here the peak and dip at 3-3.6kHz (just below the notional 3.9kHz crossover) is as likely a mistermination between the mid cone/stiff surround as any resonance associated with the horn. It's especially obvious on the CSD waterfall [Graph 2] but relatively narrowband and arguably of reduced subjective significance bearing in mind the typically low <0.2% midband THD (re. 90dB SPL). At least the resonances were consistent in our samples, ensuring a tight 1.3dB pair matching up to 7kHz with some relaxation to 1.5dB up to 20kHz where there's a 4-5dB lift in high treble. The output of the HF unit is sufficient to extend the responses to 24.8kHz and 30.9kHz [–6dB re. 10kHz; pink shaded area, Graph 1] while the magnetically-attached grille has a broadly attenuating effect above 2kHz [blue trace, Graph 1].

Bass [green shaded area, Graph 1], courtesy of the 56-350Hz/–6dB bandwidth of the woofers and substantive 38Hz output of the reflex port, extends to 35Hz (–6dB re. 200Hz) rolling away steeply below 40Hz. Meanwhile, as expected, the speaker's high sensitivity comes at the expense of a tough load as Triangle's nominal 8ohm rating is rendered moot by its 3ohm minimum spec. In practice the nominal load is 3ohm and the minimum a punishing 2.5ohm/136Hz with a sub-4ohm from 80-400Hz where the impedance phase swings through –53° to +34°. PM


Response inc. nearfield summed drivers/port [green], freefield corrected to 1m at 2.83V [yellow], ultrasonic [pink]. Left, black; right, red; w grille, blue


While HF horn modes seem well suppressed the two 1.2kHz/3kHz driver resonances are obvious

Sensitivity (SPL/1m/2.83V – 1kHz/Mean/IEC) 89.4dB / 90.2dB / 88.0dB
Impedance modulus: minimum & maximum (20Hz–20kHz) 2.53ohm @ 136Hz, 18.2ohm @ 25Hz
Impedance phase: minimum & maximum (20Hz–20kHz) –57° @ 72Hz, +44° @ 665Hz
Pair matching/Resp. error (200Hz–20kHz) 1.5dB/ ±3.3dB/±3.1dB
LF/HF extension (–6dB ref 200Hz/10kHz) 35Hz / 30.9kHz/24.8kHz
THD 100Hz/1kHz/10kHz (for 90dB SPL/1m) 0.35% / 0.15% / 1.1%
Dimensions (HWD) / Weight (each) 1128x118x169mm / 27kg
Price £3000

Triangle Distribution France
Bordeaux, France
Supplied by: SCV Electronics Ltd, Herts
03301 222500