• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Suggest a preamp project for me.

I built the preamp from DIYaudioprojects.com I used primarily recycled parts, all of which i sourced and soldered together into a nice little line stage. I am very happy with it and I am planning on building the RIAA phono pre from the same designer. If desired, tone controls can be added but I would build it as is and see how you like it first. It uses 12AX7A variants so tubes should be no problem to source or roll. If you are handy at all you can make these little things perform. Hope this helps.
 
The Mullard is certainly classic, but not really a preamp in the modern sense of the term. It's from the days of ceramic phono cartridges, crystal AM tuners, and a very high required sensitivity. Today a preamp, for those who still spin wax, has two parts, a phono equalizer (that brings the tiny output from a modern phono cartridge up to line levels) and a line stage (that selects between various line level sources, has gain control and sometimes tone controls, and usually has some flat gain of its own, maybe 10 or 20 dB).

For DIY and especially for a first project, these might be considered to be two separate gigs. As has already been suggested, the line stage might be made "passive", without a gain stage, just to get your feet wet, leaving room to add the gain if desired later. The MC30 has a high sensitivity, so is a good candidate for this.

A good phono stage is much more difficult to get right, so might be saved for later. Just some thoughts.

All good fortune,
Chris
 
As a starter I'm thinking of building Eli Duttmans' version of the RCA phono schematic.
Full_Tweaked_RCA_Phono_Stage10.jpg
 
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A phono preamp is not a simple project. Definitely look before you leap.

JMO, the tweaked RCA setup is good, without being highly complicated. Those folks who've built the setup are happy. ;) I've uploaded a graphic for a cost effective PSU that's quite suitable.

Contact member Jeff Yourison to obtain the benefit of his construction experience.
 

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