Author Topic: Sansui AU111 Valve Amplifier  (Read 22593 times)

Offline King_Julian_S

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Re: Sansui AU111 Valve Amplifier
« Reply #45 on: January 10, 2014, 08:15:15 AM »
Alan designed and Jimmy build it..
I will PM you Jimmy's nr...
Non audiophile music lover...

Offline Ampdog

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Re: Sansui AU111 Valve Amplifier
« Reply #46 on: January 10, 2014, 03:38:33 PM »
When refurbishing I only exchange two electrolytic caps of rediculously high value, for polyesters.

Going back somewhat, I have been alerted in PM that I created a misunderstanding here. I did not mean that when refurbishing I replace only those two caps; I meant those are the only circuit values (per channel) that I change; values of all other components are in order.

For those interested and with access to a schematic: Phono input capacitors C1 and C2 of 5F. The input impedance of that circuit is never less than 30K, thus a 470nF capacitor only is needed to reach <10 Hz. Then C59, C60: The output impedance of that circuit is 2K at minimum, meaning that it can hardly drive anything lower than 5K satisfactorily. For that a value of 470nF is sufficient to reach <20kHz.

But as said that is not the topic here. Previous posts will give more information.

Audio must be the only branch of engineering where lack of basics' knowledge is considered a superior form of wisdom. (Anon)