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Question about the Sigma Project
#2
Hi makinrose

Sigma nominally has a low-z output due to the feedback around the mixing stage. You should build it as is and try it with a long cable and a short cable to hear if there's a difference. If there, the best solution is to add a BJT buffer directly to the mix stage plate. Surprisingly, this provides a better frequency response than a mosfet would.

Have fun
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Messages In This Thread
Question about the Sigma Project - by makinrose - 01-05-2019, 12:21 AM
RE: Question about the Sigma Project - by K O'Connor - 01-05-2019, 12:29 AM

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