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Old 14th December 2010, 06:58 PM   #1
lausar is offline lausar  United States
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Question Threshold NS10 Gain?

I purchased a NS10 recently and have spent a few hours reviewing all of the threads about this preamp, renewing it, modding it and cloning it, etc.
I'm going to the the 'renew' route but I really need to lower the gain. The spec for the line level section is 20dB and I want to lower it to 10dB. I'm using external -10dB bullets for now but is there something better I can do with a circuit mod?
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Old 14th December 2010, 07:21 PM   #2
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either replace 4K75 ( connected from output to emiter of input transistor) - with 2K2, or solder another 4K75 across original one
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Old 14th December 2010, 07:59 PM   #3
lausar is offline lausar  United States
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either replace 4K75 ( connected from output to emiter of input transistor) - with 2K2, or solder another 4K75 across original one
Will this lower the gain for the phono section also? Does the phono stage module go through the high level section to output?
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Old 5th January 2011, 06:48 PM   #4
lausar is offline lausar  United States
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either replace 4K75 ( connected from output to emiter of input transistor) - with 2K2, or solder another 4K75 across original one
Thanks Zen Mod. Definitely dropped the gain to my liking. I know I'm late to the party with the NS10, removing the tant's is a move in the right direct. Now I'm on to the phono boards and lastly the p/s caps.
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Old 5th January 2011, 07:25 PM   #5
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either replace 4K75 ( connected from output to emiter of input transistor) - with 2K2, or solder another 4K75 across original one

IMO It`s better to double the value of 300 Ohms feedback resistor (the one in series with two 220uF caps) `cos loading output with 2K2 is a bit of "stress"
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Old 5th January 2011, 09:07 PM   #6
lausar is offline lausar  United States
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IMO It`s better to double the value of 300 Ohms feedback resistor (the one in series with two 220uF caps) `cos loading output with 2K2 is a bit of "stress"
Can you elaborate on that "stress".
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Old 6th January 2011, 08:32 AM   #7
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Feedback network is a load for the output stage, so this way you`re driving ~ 2K5 load.
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Old 6th January 2011, 07:45 PM   #8
lausar is offline lausar  United States
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Feedback network is a load for the output stage, so this way you`re driving ~ 2K5 load.
So leave the 2.2kohm in place and double the 300ohm or go back to the original 47.5kohm and double the 300ohm?
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Old 7th January 2011, 09:52 AM   #9
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Go back to the original 47.5kohm and double the 300ohm.
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