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Hoffman Amps Forum image Author Topic: DR103 Preamp build  (Read 56 times)

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Offline hiegdk

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DR103 Preamp build
« on: November 20, 2025, 06:57:48 pm »
I'm considering building a standalone preamp based on the DR103 circuit here: https://hiwatt.org/Schematics/DR_PreLinkedInput_v1.gif

How should the Output 1, Output 2, and OT tap connections be handled? I suppose I should be ommiting V4? If the intent is to simply have an output suitable for running into a power amp what modifications should I be making? Thanks!

Offline tubeswell

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Re: DR103 Preamp build
« Reply #1 on: November 20, 2025, 09:53:17 pm »
Yes, for that particular preamp, as a stand alone preamp I agree. Just keep V1, V2 and V3 and leave out the LTP. The CF will be ideal for driving the signal cable to your power amp etc.
A bus stops at a bus station. A train stops at a train station. On my desk, I have a work station.

Offline hiegdk

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Re: DR103 Preamp build
« Reply #2 on: November 20, 2025, 11:29:43 pm »
Is it possible to retain the Presence control in that case? Would I just source the tap from pin 3 of V3?

 


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