Will preamp manufacturers tell you if the model is phase inverse?

Thats a good question

What i never understood is if the circuit inverts polarity why doesn’t a manufacturer simply reverse the leads heading to the component’s output so that once leaving the component polarity isn’t reversed any longer.

some preamp may be easy to do like this, most may require an extra stage.

Wait.  So Rogue told you the RP1 inverts both line and phono, but JA's measurements in Stereophile showed that the phono does not invert?  Seems odd to have a manufacturer give you the wrong specs.  

I just heard back from Nick at Rogue. The RP-1 and the RP-5 Both invert phase on ALL inputs (including phono).

 

So Rogue told you the RP1 inverts both line and phono, but JA's measurements in Stereophile showed that the phono does not invert?  Seems odd to have a manufacturer give you the wrong specs.

although phono stage preserved absolute polarity and line inputs stage inverted absolute polarity, the preamp output still inverted absolute polarity!

Remember that you want to take the entire amplification chain into account. So (for example) if you have:

• Phono stage (non-inverting)
• Line stage (inverting)
• Amplifier (inverting)

Then your signal path is non-inverting.  With multiple sources, you might have one source which results in an inverted signal and another that does not.

Cheers,
Thom @ Galibier Design