AHB2 - "This stable and load-independent behavior ... is something not often encountered"
"This stable and load-independent behavior of the output stage is something not often encountered and adds, of course, another positive point for the device."
"AHB2's output power, near its clipping limit, was measured at 108Wrms per channel into 8 Ohm loads and at 190Wrms per channel at 4 Ohm loads, easily confirming the specs given by the company itself."
"Based on this performance, the amplifier seems more than capable of driving difficult loads."
"Damping factor was estimated above 200, therefore, no system frequency response discrepancies, due to loudspeaker's impedance variability, should be expected."
"In distortion measurements, AHB2's behavior was impressive with a total harmonic distortion and noise (THD+N) figure at 0.0009% for 8 Ohm loads and 0.0012% for 4 Ohm loads (measured at 1/3 of its maximum power) and harmonic distortion at 0.0005% and 0.0009% for 8 and 4 Ohm loads respectively."
"Intermodulation distortion (SMPTE) was also low, at 0.0005% and 0.0007% (8/4 Ohm loads). This performance clearly shows that the Benchmark/THX design approach works in practice as intended (at least from the distortion point of view) and the result is a power stage with very low distortion, indeed."
"The frequency response of the amplifier (with an 8 Ohm load) was practically flat with a slight attenuation towards the high-frequency part of the spectrum which is very progressive and does not exceed 0.3dBr at 60kHz."
"The noise performance of the amplifier was, also, top-class. With a reference level corresponding to 1Wmrs/8 Ohm, the signal to noise ratio was measured at -109dBr (A) (with a 1kHz input signal) and the dynamic range at 129dB."
"In both spectrum graphs, there is an apparent absence of noise components from the power supply and their intermodulation products in the low-frequency range (the 50Hz component is hardly distinguishable), all of them being below -130dBr. This is a remarkable behavior, especially with the output stage under load conditions, which justifies the choice of a switch-mode power supply."
"Finally, the square wave response shows a very good transient behavior, without any particular problem. Slew rate was estimated at 16V/uS and rise time at 3.5mS, a value that corresponds to a conventionally calculated bandwidth of 100kHz."
- Dimitris Stamatakos, AVMENTOR.net
AHB2 - Class A Recommended Component - Fall 2018 - Power Amps
'Class A' is Stereophile's highest classification for recommended components. Very few components receive this elite classification. Stereophile defines 'Class A' as follows:
"Best attainable sound for a component of its kind, almost without practical considerations; "the least musical compromise." A Class A system is one for which you don't have to make a leap of faith to believe that you're hearing the real thing."
DAC3 HGC - Class A+ Recommended Component - Fall 2018 - Digital Processors
'Class A+' is Stereophile's highest classification for digital processors. Stereophile defines Class A and the digital processor Class A+ as follows:
"Best attainable sound for a component of its kind, almost without practical considerations; "the least musical compromise." A Class A system is one for which you don't have to make a leap of faith to believe that you're hearing the real thing. With Super Audio CD, DVD-Audio, and Hi-Rez PCM and DSD files now available, we have created a new Class, A+, for the best performance in those digital categories."
AHB2 - "Tightness, accuracy and punch"
"The most identifiable positive trait (there are many) of the AHB2, and that is low end control. Tightness, accuracy and punch."
"The AHB2 has power in spades, especially with two units running in mono mode."
"A single amp in stereo will suffice for most normal situations, and was in full control of all sonic responsibilities with every pair of loudspeakers we threw at it."
"The low end tightness and thrust is just where it should be, and pass though information is the name of the game."
"The sound of the amplifier is true to source and one that takes many queues from the production world of balance and monitoring."
"... will rock the house (or sooth the baby to sleep)."