Building a 6x DI Box 19 inch rack - am I missing anything?

[PhilipMarlowe]

This impedance stuff is a bit confusing, to say the least, so I want to ask more knowledgable people before jumping into this DIY project.

So I want to build a DI box 19 inch rack as cheaply as possible but with quality transformers (specifically the Lundahl 1935s since they can be run passively afaik. I also listened to many comparisons and I just like Lundahl transformers the best from all other commercially available ones.

It should effectively work like the Radial JD6, only with different transformers and less features I don't need.

From what I gathered the circuit should not be a complex one, and if I see correctly it would in theory be possible without printing PCB boards.

My use case would be running instruments (guitars, bass), synths, drum machines (MPC Live and Elektron) and lastly DAW Line signals from my interface's DA (reamping) for mixing through this DI into my mixer which has mic pres on 6 of its channels. Effectively I would have a chain that goes through multiple transformers before going into the box again (fuck yeah!)
Would there be any impedance issue regarding the Lundahl 1935 that I should be aware of, since I want it to be able to handle any source I throw at it? Would I even need a pad?

Just to clarify: I have some experience building DIY equipment and modding gear.

Thanks guys!

 

[moamps]

I think your plan looks basically ok. The only thing you need to be careful not to overload the transformers (and mixer preamps) with too high signal from DAW or other devices that produce a high output signal. If you can regulate the output voltage on these devices, then you don't even need a "pad".
I'm not a fan of using passive DI-boxes for high-impedance sources (EM or piezo pickups), so I suggest you to try one transformer before buying more transformers and see if the sound you get is ok.

 

[PhilipMarlowe]

I think your plan looks basically ok. The only thing you need to be careful not to overload the transformers (and mixer preamps) with too high signal from DAW or other devices that produce a high output signal. If you can regulate the output voltage on these devices, then you don't even need a "pad".
I'm not a fan of using passive DI-boxes for high-impedance sources (EM or piezo pickups), so I suggest you to try one transformer before buying more transformers and see if the sound you get is ok.

Thanks and will do! I might hold off for now though since this shortage is screwing with my diy plans...