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Yamaha
C1000
The
largest in the Yamaha range, delivering 86W per channel (both
driven) into two switchable pairs of loudspeaker outputs, available
on spring loaded locks for ease of connection. The mains lead is 2
core, and feeds through to two switched
and two unswitched mains outlet sockets. An unusual coaxial socket
is provided for 75 ohm FM aerial connection but fortunately this is
duplicated with 75 ohm and 300ohm FM aerial terminals. (Yamaha should
change the, socket to a more normal type.) Phono sockets throughout
are used for audio connections, and inputs include pick-ups 1 and 2,
auxiliary 1 and 2, and input and output connections to two separate
tape recorders. Front panel controls allow monitoring of either
recorder or, alternatively, copying from either one to the other.
Phono break points are provided for insertion of external equipment
immediately prior to the main amplifier. Two earth terminals are
provided on the rear. Pick-up input 1 has three switched impedances
of 28k ohms, 41k ohms and 62k ohms (as measured). The receiver is
very heavy and is mounted in a large wooden case with a metal
ventilation grill, and even when pushed hard it only attained a warm
temperature. The general styling is most impressive, but the
ergonomics are highly personal and clearly many will find the
controls fascinating and helpful, whilst others will at first be
confused. All the tone controls are ganged and have 11 stepped
positions on a horizontal click stop slider arrangement, which worked
well. The loudness control was similar, allowing its effect to be
gradually increased as desired. The balance control was a centre
indented normal horizontal slider. The turnover frequencies of the
tone controls can be set at 250 or 500Hz for bass, and 2.5kHz and
5kHz for treble. The rumble filter cutting at 12dB per octave rolls
off steeply below either 20Hz or 50Hz (excellent). The treble filter
is switchable at 7kHz and 14kHz for 3dB points. A rather small rotary
volume control is provided but a separate slider microphone gain
control is also incorporated. An additional slider operates FM muting
level. A row of neat lever paddles select inputs, operate tape
functions and also mono/stereo combinations, and loudness switch.
Stereo jacks are provided for microphone and headphone connections
and adequate volume was given for the latter. The tuning mechanism is
a delight to use and the dial accuracy superb. Signal strength and
tuning meters are provided.
The
amplifier's reproduction quality was clearly good but it must be
judged by the highest standards, because of the price. Some bass
sogginess was clearly audible to all of us. The treble end was liked.
Very extensive IM sweep tests were made which confirmed the results
of the listening tests. In particular they showed a relatively poor
IM performance at the bass end. The half power bandwidth for 0.1 %
was very good, extending to at least 20kHz. Harmonics distortion and
SMPTE IM distortion measured well, but the latter began to increase
slightly at low levels. The damping factor was excellent. No DC
output problems were noted (output circuits relay protected). The
signal to noise ratios throughout were excellent. The volume control
tracked rather poorly below -30dB. The remaining controls tracked
well. The tone controls all provided excellent variation. The pick-up
input amplifier had an excellent clipping margin and its output level
was well compatible with that of the tuner. All the input and
monitoring functions are FET switched to avoid clicks. Auxiliary and
tape in/out impedances and sensitivities were very compatible (nb.but
not directly with DIN standard equipment).
The
signal to noise ratios of the tuner were superb. The distortion
measurements were in general very good, but full deviation of R-L was
rather poor. But in practice this is not too serious in this case.
The crosstalk measurements were average and adequate. The frequency
response was very good whilst the MPX filter was excellent. RF input
sensitivities were superb. Adjacent and alternate channel
selectivities, image response, IF breakthrough, capture ratio and AM
rejection measurements were excellent, RF IM ratio was good. The
limit threshold also measured well. The tuner section gave excellent
results on both the test and normal broadcast programmes. The tuning
knob when touched switches off AFC for ease of tuning.
This
is a very expensive receiver and whilst it gives a very good
quality, a few others were cheaper at a discount. Stylistically,
though, Yamaha must be strongly commended, and the electromagnetic
compatibility was remarkably good. It can be said to be fair value
for money and can be recommended if you are not concerned with price.
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This article featured in the Hi-Fi Choice 'Consumer
Guide' 1976 and was written be Angus McKenzie. We thank Hi-Fi Choice
for their kind permission to display this review.
http://www.hifichoice.co.uk/ |
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