How to reamp into preamps (repreamp?)

[Paul W]

I'm thinking of doing some controlled experiments on preamps and it seems like it ought to be easy (in principle) to play mic-level recorded signals into preamps for very controlled experiments.

I'm familiar with reamp boxes that generate instrument-level signals for guitar amps and pedals, but I don't recall hearing about re-preamping boxes that generate mic-level signals.

Is that a thing? How would I go about that?

Related question: are there any archives or other good sources of pristine recordings of mic-level signals (presumably through high-end "clean" preamps and converters), for such experiments?

It seems like there ought to be, and it ought to be comparatively easy to compare preamps (at least relative to things like compressors), running varied standard clips through them at different gain levels to see what "color" you get (or not). (And maybe with a few different output impedance levels from the repreamp box?)

 

[pmfalcman]

A passive DI box?
They're meant to convert hi-Z line output to low-Z mic level after all, right?
Unless the hi-Z to low-Z part causes issues it should do the trick.

 

[Khron]

They're meant to convert hi-Z line output to low-Z mic level

* instrument output

(Line-to-mic, especially if galvanic isolation is not necessary and/or the line-level source is balanced, can simply be achieved with a resistive pad / attenuator)