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Nagra –
HD DAC
Burn-in period
In order to obtain optimal performance from the Nagra HD DAC, it is preferable to
leave the device switched on for about 15 minutes before use, so that the internal
components can reach their optimum operating temperature.
Like all tube electronic devices, the Nagra HD DAC needs a running-in period. It
will reach peak performance after a few hundred hours operation.
Tube ageing
Please check in the Menu to see how many hours your tube has been operating.
The HD DAC tube is a high grade military tube selected by Nagra according to
exacting criteria. Their theoretical minimum useful life is 5000 hours. Actually,
some tubes operate consistently for more than 10 000 hours.
Thus, the useful life of the tubes is somewhat unpredictable. Rather than
replacing the tubes arbitrarily after 5000 hours, we suggest that you identify the
signs of ageing:
The distortion gently increases to an audible level;
Presence of clicks (dry and short noise, like breaking dead wood);
Presence of pops, short noise in the low frequencies;
Presence of hiss, higher background noise.
As soon as one of these signs appears, please contact your Nagra dealer to order
a HD DAC replacement tube kit, reference 7055761000.
Case cleaning
Clean the HD DAC casing using a soft, non-fluffy, slightly damp cloth. Do not use
any cleaning products which could have a corrosive effect.
