Mastering during the era you are referring to was mainly different than it is for today.
First, mastering was for vinyl. LP/45's
RIAA equalization curves were rather fixed for the following reasons.
1. To get at least 22 mins out of a side of 33.33RPM
RIAA is a cut in low freqency response (other other additions to the mid highs and super highs) to keep groove modulation on the lathe from eating time out of a record. If you allow 25HZ at full modulation (30CM/Sec)on an album..you will have roughly 3.8 mins on the entire side! Reverse RIAA is incorporated in all Phono Preamplifiers for vinyl playback, be it a receivers phono stage, high fidelity preamp, or separate phono preamp to get the output of a moving magnet phono cartidge up to line level. A ceramic cartridge is at line level but the eq had to be there or the vinyl would have "no bottom". A pre-pre amp..or Moving coil pickup preamp..abbv. MC-Phono Pre, has 2 stages of amplification or one huge stage..since MC carts have around 1/50th of the output of a moving magnet. The lathe operator used high fidelity power amplifiers to drive the cutter head and had hand manipulation of the lathe cutting width. It is an art that I miss. I use to set lathes up all the time in the late 70's. 2 track masters did benefit from countour, 2 band, 3 band and even 4 band eq-ing before master tapes were used to drive the lathe..but not in every case. Mastering back then was actually operating the lathe process and monitoring the cutting. Master 4 track 1/4" consumer format at 7 1/2 was actually a great copy of a copy of another copy of the master tape. Back then the mix was it!
Hi Bill, just started reading Bobby Owsinski's book on Mastering Engineering - he covers some of the stuff you mention about vinyl, things like having two EQ's and a notebook so while one song was playing the other EQ could be set to the next set of values, etc - interesting reading. I wasn't aware that the RIAA curve was so deep, but after seeing some of the photomicrographs of cut vinyl I can understand why. What a fine line between black art and science! Can't wait to find the time to finish the book and follow some of the resources he mentions... Steve
To Bill: I noticed a few mastering houses on the net that encourage submitting mixes in 1/2" two track format.
Is that a "prefered" format as far as sonic quality? What would you say is the percentage of mastering work you receive on on 1/2" tape?
Thanks in advance