Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: hiegdk on November 20, 2025, 06:57:48 pm

Title: DR103 Preamp build
Post by: hiegdk 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 (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!

Title: Re: DR103 Preamp build
Post by: tubeswell 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.

Title: Re: DR103 Preamp build
Post by: hiegdk 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?