Mono record sounds like stereo

So I have been playing stereo records for 40 years.  I’ve recently acquired some Verve Japanese reissues. Listening to Metronome All stars tonight and there is clearly separation. I hear horns predominantly on the left and xylophone and drums on the right.  This is on an Ortofon SPU synergy stereo cartridge. Is this normal ?  I’m sorry.  I’m new to Mono.  I bought about 50 verve and Blue notes last week and got some monos on accident.  My system is balanced and the room has extensive treatment so I’m lost !   


Yeah, that’s gonna be an interesting read because that SPU has a conical stylus I believe. So much smaller profile of my blackbird would not duplicate the problem.

Welcome to the jungle. Nowhere in audio can you find more conflicting information than on the subject of mono reproduction and mono cartridges. To begin with most modern mono cartridges are stereo cartridges that have been modified in one way or another to produce mono. Very like flipping the mono switch on your preamp.