Old reel to reel transfer

I’m wanting to get some old voice recordings off of a reel to reel tape player. The original recordings were done on a battery operated unit and the recording speed was not consistent. The playback speed in Audacity works great to compensate for that inconsistentcy, but I need to make the speed correction permanent on the digital version. Can I play on one track while recording onto another? Or some other approach?

Try the “Change Speed” effect: http://manual.audacityteam.org/o/man/change_speed.html