REW as electrical RTA without Mic?

[Z1500]

Sorry for the NEWB question, this might be super obvious to more experienced users but not to me.
I have a need to test some audio equipment for frequency output. But I would like to test without speakers or microphone connected. Just testing RCA's and speaker outputs off of varying devices. Finding crossover points and any peaks or dips in signals.
Any way to do this with REW? What sort of interface do I need?

 

[John Mulcahy]

Pretty much any audio interface, or your PC's headphone out and line in connections if it has them.

 

[Z1500]

Thank you for helping me.

Like the Focusrite Scarlett Solo?
Or something even more simple like a $20 audio capture USB adapter?

I'm wondering how ether of these devices will handle higher voltage input signals. They seem to be made for <1.0v microphone and headphone type signals. I'd like to hook it up to amplifier speaker outputs that are over 20v.

 

[John Mulcahy]

If you want to measure amplifiers you stand a pretty high chance of destroying your audio interface. To avoid that an attenuator would be needed at the interface inputs, usually with some zener clamps as an additional safety measure. Here is a DIYAudio thread from a few years ago that may help, this article is more recent.

 

[DanDan]

There are many very affordable passive monitor controllers on the market. The TC Level Pilot is only about 20 Bucks. For a bit more you can get balanced ones with combi input connectors.
These devices would have an input Z of say 10K, perfectly safe for your amps or other electronics.

 

[trobbins]

Z1500, your aim has been in widespread use for many years - a few google searches using REW and amp testing will identify a lot of experience and guidelines and example results that should inspire you (and there is a lot of earlier software offerings that started amp testing activity over a decade ago). I've even used $1 USB adaptors. I suggest you read widely first about benefits and pitfalls.