Does the Drop THX AAA 789 drive the Beyerdynamic DT 990 Pro?

Computed from measured specifications · target SPL 110 dB · load 300 Ω

Adequate

The Drop THX AAA 789 adequately drives the Beyerdynamic DT 990 Pro with limited margin (~6.4 dB headroom at 300 ohms; needs ~46.2 mW, delivers 200 mW).

Headroom
6.4 dB
Required (110 dB SPL)
46.2 mW
Delivered (@ 300 Ω)
200 mW
Required voltage
3.52 Vrms

Power Headroom

Headroom: 6.4 dB 0 · target 6.4 dB below target marginal adequate ample -14 dB +10 +20 +36 dB

Scale shows dB headroom above the 46.2 mW required to reach 110 dB SPL. Amp delivers 200 mW at 300 Ω (+6.4 dB above target).

Beyerdynamic DT 990 Pro Dynamic · over-ear
Impedance (rated) 250 Ω
Impedance (measured) Source: reference-audio-analyzer.pro/en/r… 267.6 Ω measured
Sensitivity (rated) 96.0 dB/mW
Sensitivity (measured) 93.35 dB/mW measured
Driver Dynamic
Spec basis Measured
Measured by Reference Audio Analyzer (https://reference-audio-analyzer.pro/en/report/hp/beyerdynamic-dt-990-pro-250.php) · Source ↗
Drop THX AAA 789 Desktop Ss · Single Ended
Output impedance manufacturer 0.1 Ω
Power @ 16 Ω 3000 mW
Power @ 32 Ω 1800 mW
Power @ 300 Ω 200 mW
Power @ 600 Ω 100 mW
Power source Manufacturer
Drop product page SE figures: 3000/1800/200/100 mW at 16/32/300/600 Ω. THX AAA topology, output impedance <0.1 Ω (class spec). · Source ↗

Where to buy

Drop THX AAA 789 on Amazon ↗ Beyerdynamic DT 990 Pro on Amazon ↗

Disclosure: links above are Amazon affiliate links. As an Amazon Associate this site earns from qualifying purchases — at no extra cost to you. Affiliate commissions do not influence verdicts; all analysis is computed independently from the data.

AmplifierHeadroom
Schiit Lyr 3 Ample 12.9 dB
Schiit Valhalla 2 Ample 12.4 dB
JDS Labs Atom Amp 2 Adequate 7.9 dB
Topping L30 Adequate 7.8 dB
iFi Zen DAC V2 Insufficient -1.1 dB
Apple USB-C to 3.5mm Insufficient -11.5 dB

See all amplifiers for the Beyerdynamic DT 990 Pro →

HeadphoneHeadroom
Koss Porta Pro Ample 28.2 dB
Grado SR80x Ample 27.9 dB
HiFiMan Arya Ample 17.5 dB
AKG K702 Ample 16.9 dB
Audio-Technica ATH-R70x Adequate 8.0 dB
Beyerdynamic DT 770 Pro 250 Adequate 7.5 dB

See all headphones for the Drop THX AAA 789 →