INNOVATIVE DESIGN
Our time, effort and money have been spent developing the circuit and building the amplifier, using the highest specification components throughout. We've included useful features such as a switchable direct input and pre-out into the design, to allow you to use the Aethos in a wide variety of systems. The headphone jack has been integrated so that speaker switching is performed by the output pause relay so as not to obstruct the signal path and degrade sound quality.
Rega has taken the design concepts used for the award-winning Elex-R and Elicit-R and taken them to the next level with a 125 watt dual mono design and features such as a fully discrete FET line amplifier, polypropylene capacitors throughout amplifier, K-Power capacitors, regulated power supply for the power amplifier and a high current output stage consisting of four 160w Sanken output transistors per channel.
VOLUME CONTROL AND LINE AMPLIFIER TECHNOLOGY
Aethos uses a high performance volume control that operates in both feedback and passive mode, plus a line amplifier originally developed for the Elex-R. The Aethos volume control and line amplifier stages have been upgraded to discrete FET input op amps using the LSK389 FET system and RK27 'Blue Velvet' potentiometer. The feedback and input levels are varied to set the required volume level. The level and tracking between the two channels is set more by the closed-tolerance parts of the pre-amp circuit than by the actual pot, thus minimizing discrepancies between channels due to volume control tracking irregularities, further improving the performance of the RK27 potentiometer. This method not only reduces tracking irregularities but also reduces input overload and noise as the control 'uses' only as much gain as needed to amplify the signal. This form of volume control is normally found in professional broadcast environments where careful control of noise levels is required.
POWER AMPLIFIER TECHNOLOGY
The power amplifier used in the Aethos is an improved version of the one used in the Elicit-R and Elex-R amplifiers.
The power amplifier used in the Aethos was born after a long search by our engineers to develop a Class A emitter-follower driver stage with a low source impedance. The whole thing is based on two complementary pairs of 160W Sanken Darlington output transistors.
The technical and sonic benefits obtained by using low impedance drivers are well known, but, in any case, they can create high permanent currents in the driver stage using standard transistor configurations.
The combination of a low impedance driver with Sanken Darlington transistors, with their internal low static current thermal bias network, allows for a Class A emitter-follower driver stage with excellent thermal stability and low static currents in the driver stage.
Due to the nature of Rega power circuits we are able to use two complete output stages in parallel. This includes the output transistors, bias network and the preamp driver transistor rather than just the output transistors as usual.
This ensures that 125W output can be reached with ease.
Output power with 230/115 V power supply
125 W RMS, both channels into 8 Ω
156 W RMS, both channels into 6 Ω
NB: Continuous use at a high level at 6 Ω could cause the ambient temperature to exceed 40°C and consequently activate the thermal protection.
Headphone output
No load 12.5V
32Ω 2.7V
54 ohms 4V
300 ohms 9V
Source impedance 109 Ω
Exit Registration
Recording output 219 mV
Record Output Impedance 560 Ω
Preamplifier output
Preamplifier output 840 mV
Preamplifier output impedance 100 Ω
Input sensitivity
Inputs 1-5 and Recording input 224 mV @ 17 kΩ
Maximum input level 11.5 V (overload point of recorder output)
Direct input sensitivity 840 mV @ 50 kΩ
Power stage gain 31.6 dB
Frequency Response @ 100W into 8Ω
Inputs 1-5 and Record input 10 Hz (-0.8 dB) – 30 kHz (-0.5 dB)
Direct Input 10Hz (-0.8dB) – 50kHz (-0.5dB)
THD+Noise @ 100W, 8Ω
Direct Input (Power Stage) Typically 0.007% @ 1kHz (in the 22Hz – 30kHz band)
Line Input Typically 0.007% @ 1kHz (in the 22Hz – 30KHz band)
Consumption
Maximum output 415 W @ 230/220/115/100 V into 124 W RMS load into 8 Ω
Fuses
T3.15 AL 250V – 230V/ 50Hz and 220V / 60Hz
T6.3 AL 250V – 115V / 60Hz and 100V 50/60Hz
Dimensions
433 x 95 x 360 mm (W x H x D, including speaker terminals)
Weight
17.5Kg
