Technics SU-8080 Amplifier Review
One of the amplifiers from Technics, the SU-8080 is in the brown cabinet styling with a clear but unobtrusive front panel layout. With the exception of the front panel headphone jack socket, all connections are at the rear of the amplifier, including connections for two sets of loudspeakers and phono connectors for all signals, except for a DIN compatible connector for one of the two tape unit connections.
Input source selection is by one of the high class rotary switches which allows the choice of a tuner or auxiliary high level input and two magnetic phono cartridge inputs all of which had reasonable sensitivities and overload margins. Whilst the phono inputs have slide-switch selection of the input resistance (24k or 47k measured) and input capacitance over the range 180pF or 410pF, it is felt that the input capacitance of the high level inputs is on the high side at 350pF.
Crosstalk between input sources was virtually non-existant, and that across the tape monitor switch, which can monitor either tape unit, was to a high standard. A further rotary switch allows recordings to be made from the input source, or for either tape unit to dub to the other tape unit.
Loudspeaker outputs are selected by a further rotary switch which allows either or both loudspeakers to be connected; with the headphone jack permanently in circuit. Examination of the power output capabilities shows that the amplifier is very happy to work into either 8 ohms or 4 ohms, but that disaster strikes if the load is reduced to 2 ohms. It is therefore necessary to be careful about the choice of loudspeaker impedance in relation to frequency if either single 4 ohm loudspeakers are to be used, or pairs of 8 ohm loudspeakers.
The combined effect of the analog volume control and the 14dB muting switch offered very good control of the amplifier output into either loudspeakers of headphones, the output noise performance being very good even into headphones. Similarly, the phono input noise was outstandingly good and the noise from other sources was to a high standard with a resultingly excellent dynamic range.
The power bandwidth and all forms of distortion within the audio frequency band were to a very high standard with the high frequency intermodulation distortion at low power levels also being excellent.
Both the tone controls and the filter arrangements of the Technics SU-8080 are unusual and decidedly practical, it being clear that the manufacturer has given serious thought to the problem of what is really necessary. For instance, the eleven position bass and treble controls have their range limited to ±7dB at 100Hz and 10kHz respectively. Such a range is quite adequate for any high quality listening and any further compensation is completely unnecessary and if used, often leads to distortion. Likewise many high pass filters are ill designed, but the Technics SU-8080 includes a switchable high pass filter in the pick-up inputs where it is wanted, and furthermore it rolls off at the right frequency â€" 30Hz.
Two further filters are provided, a low pass switchable filter with a â€"3dB point at 10kHz and a sensible rate of attenuation, and also a high pass filter which operates about 2Hz and blocks the direct current path through the amplifier which is normally direct coupled.
The final controls are a very good balance control, a mono/stereo, switch, and the inevitable loudness control. Quality and operational characteristics were first class, the overall standard of construction was excellent and subjective testing offered good performance.