I grew up with my dad's Ampex tape machine and hundreds of prerecorded tapes, jazz and classical. The tapes were all 7.5 ips. Back then turntables, tonearms and cartridges were not near the quality they are today and in spite of considerable tape his the Tapes were vastly superior to LPs. Today the situation has been reversed. Modern upper level turntable playback especially with 45 rpm records recorded from uncompressed files are vastly superior (and quieter) than those old tapes. I can not speak for 15 ips modern transfers as I have no experience with them.
