Line into mic pre - how is it designed?

Hello, I did a futile serach for this Q, hope someone can enlighten me:

How are line inputs handled in (different designs of) preamps? Are line signals simply padded down and sent through the full path, like a mic signal, or do they skip the I/P transformer, like a DI input? Or something else? (I just became aware of DI inputs bypassing the x-former, (due to impedance issues i guess) so external DI's are needed to get the full character of the preamp).
I'm wondering if eg. running a line signal though a, say, Neve pre will give "neve character" or if something gets 'skipped'.

All comments appreciated! :sam:

Some classic designs used different transformer taps in one trafo - Calrec used a 1k2 1:3 tap for mic in and switched to a 10kohm 1:1 tap for line input on separate connectors.

Classic Neve ala 107x 108x used two transformers, one for each input and switch post trafo for the various signals. This allowed them to provide appropriate step-up/down ratios and correct impedances for each source.

-Tom

for "Cheap" read: "Less rare". :green:

keef

so external DI's are needed to get the full character of the preamp

Click to expand...

just fyi, some transformer input preamps use a buffer for the DI signal and then run that into the transformer for the full color of the preamp...

Thank you all, great info! :thumb: :sam:
Gotta look at a few schem's.

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