T+A P 3100 HV Preamplifier Lab Report

Lab Report

If the technical prowess of T+A's flagship preamplifier was never in doubt [HFN Sep '14] then this latest P 3100 HV iteration pushes and polishes the performance still further. Once again, it offers a maximum +14.3dB gain (balanced) with a custom volume control that acts in 1dB steps over a 60dB range with ±0.1dB overall accuracy, over an 80dB range with ±0.2dB accuracy and 90dB with just ±0.3dB variance – this is a very tight tolerance indeed and matched by very few other preamplifiers. Distortion, meanwhile, inches downwards further still from a minuscule 0.00007-0.00025% to 0.00005-0.00024% here [20Hz-20kHz re. 0dBV – see Graph 2, below] while maintaining its wide 102dB A-wtd S/N ratio and very low –99.1dBV (11µV) residual noise. Maximum output is a prodigious 17.5V – driving any power amp on the planet – while the input overload is >12V.

Arguably, the most significant change to the design of the 3000/3100 lies in the removal of all but one coupling capacitor while stabilising the DC performance of the preamp without recourse to a servo. So, where the output impedance of the P 3000 HV 'increased' from 45ohm (100Hz-20kHz) to 47ohm at 20Hz, the P 3100 HV's source impedance remains flat to within ±0.1dB from 20Hz-100kHz. Moreover

while the HF response of both preamps extends to –0.02dB/20kHz the 3000's 'dip' in low frequency response to –0.5dB/1Hz is absent in the P 3100 HV which is flat to below 1Hz [see Graph 1, below]. While this adaption in frequency response will not be audible per se, the elimination of DC-blocking caps and absence of a DC servo may well exert some subjective benefit at very high as well as very low frequencies. PM


Output impedance versus frequency (red) and frequency response (black) re. 0dBV, balanced output


Distortion versus extended frequency at 0dBV, balanced line input/output (left, black; right, red)

Maximum output/input (<1% THD) 17.5V (balanced)
Output imp. (20Hz–20kHz/100kHz) 44-45ohm / 45ohm
Frequency resp. (20Hz–20kHz/100kHz) +0.00 to –0.02dB / –0.45dB
Input sensitivity (re. 0dBV) 190mV
Input overload 12.5V (balanced)
A-wtd S/N ratio (re. 0dBV) 101.8dB
Distortion (20Hz-20kHz, 0dBV) 0.00005–0.00024%
Power consumption 49W (analogue PSU) / 5W (dig)
Dimensions (WHD) / Weight 460x170x460mm / 28kg
Price £12,690 (Phono module, £1088)

T+A elektroakustik GmbH & Co. KG
Supplied by: Kog Audio, UK
024 7722 0650