New pre-amp has three RCA inputs, need four

Luther's solution is nice, but if you're not in the mood to DIY and/or invest in a high-zoot switch box...

An inexpensive source selector switch is... an inexpensive solution.

For the price, you can try one, and -- if you find it too degrading of a signal put through it (relative to mainlining the same source into a preamp input), just sell it, karma it, or pitch it.

They're readily available from the usual suspects

Here's one that's actually fairly expensive and overkill (as an A/V switch, it has three analog channels, L/R/V per source):
https://www.parts-express.com/parts-express-s-video-audio-and-composite-video-selector-switch-5-in-2-out--180-938

EDIT: Here's a more... modest option, from the erstwhile MCM Electronics fine family of products (now part of Newark):
https://www.newark.com/mcm/50-6175/switch-box-four-input-source/dp/39C0728?st=audio switch box



FWIW, I use one of these (the black AZDEN box -- the silver box is a 'passive preamp' with a TVC and a three-source input selector, too), but they're not particularly easy to find on any given day.


009 by Mark Hardy, on Flickr

A similar but somewhat more sophisticated (but also still completely passive) product was offered by dBx -- these are meant primarily for input and output control/dubbing for recording (analog tape recording ) but, I think, can be repurposed as source selectors. They're cheap and plentiful -- I bought one for ca. $25 on eBAY a few years back.




Ol' Radio Shack (bless their hearts) were the go-to for stuff like analog switch boxes in olden times... heck, they might even still offer one nowadays on their website -- who knows?

No cassette deck? No eight track?



(actually, and in all seriousness, I do still have a cassette deck - dual well! - hooked up to the big-boy hifi upstairs. Just in case, you know?)



(older photo -- but you get the idea )

oh, on topic -- there's always the nuclear option when it comes to source selectors... it will require adapting some of one's patch cords interconnects and/or speaker wires cables to 1/4 inch "phone plugs", but that's a small price to pay for flexibility, right?

011 by Mark Hardy, on Flickr
014 by Mark Hardy, on Flickr

a bit, yeah

They're not hard to find, nor particularly expensive.
Switchcraft also made some less Baroque switchboxes which may be cheaper if one can find one. Heck, maybe they still do?

The old "audio comparators" much beloved of 1970s hifi stores are expensive (but quite cool).

^^^ good point. I was wonderin' whether one input position might be either balanced or unbalanced.

delkal wrote: »

mhardy6647 wrote: »

^^^ good point. I was wonderin' whether one input position might be either balanced or unbalanced.

That is usually how it is. No idea what would happen if you plugged two different inputs in both (and I wouldn't want to try)

Like crossing the streams in Ghostbusters.

sans potentiometer is probably better for an input selector. I doubt that the attenuator in the Schiit Sys provides a constant impedance.

Nothing (including the cheap switchboxes I myself recommended earlier in this thread) adds no distortion when patched into the signal chain. That Schiit thing is fine as a "passive preamp" but is probably too complicated (i.e., having an attenuator on board) for its own good just to add an additional line level, unbalanced source input (IMO, IME, YMMV, et cetera, et cetera, et cetera).