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Old 18th September 2011, 11:26 AM   #11
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Join Date: May 2007
Hey SY,

, actually the sheet didnīt say anything at all. Found the awkward info in a review.

This is my idea how a cascode, if it for some reason must be, should be used:
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Old 18th September 2011, 02:51 PM   #12
DF96 is offline DF96  England
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If you want 6 or 12dB gain, you don't use a cascode.

If you want lowish output impedance, you don't use a cascode. (NB. in a preamp you will want low output impedance, unless you are incompetent).

If you are serious about valves, you don't hang them out horizontally at the back of the chassis, even with fancy roll-bars. This is asking for poor contact as the valve slowly drops out of the socket, and the risk of 'beverage contamination'.
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Old 6th July 2012, 09:34 AM   #13
Tax is offline Tax  Australia
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Location: Sydney
Quote:
Originally Posted by DF96 View Post
If you want 6 or 12dB gain, you don't use a cascode.

If you want lowish output impedance, you don't use a cascode. (NB. in a preamp you will want low output impedance, unless you are incompetent).

If you are serious about valves, you don't hang them out horizontally at the back of the chassis, even with fancy roll-bars. This is asking for poor contact as the valve slowly drops out of the socket, and the risk of 'beverage contamination'.

I have a borrowed CF-080LSX preamp in my system. Yes the valves hang horizontally at the back but they use an extremely good socket that has a GRIP on the valve that I have not experienced in any other valve amp before. It is not easy to even 'intentionally' put a valve in a take one out without a bit of brute strength.
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Old 6th July 2012, 11:34 AM   #14
DF96 is offline DF96  England
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This means risk of damage such as glass cracking around the pins. Modern valve bases often grip a bit too tightly.
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