Continued from Part 1…
In our last session my client and I were in the mastering suite — now we’re in the lathe room. I’ve got my high res vinyl-centric files lined up. Now I have to ask myself a lot of questions. How loud can I get this and still fit the program on the side? Is it going to sound good all the way in to the center of the disk? No, probably not. How much high frequency stuff is going on here? — in the vocals and cymbals?
The vocal is waaaaaay back in an Aztec temple chamber — no worry about lancing ssss sibilance messing playback up. Some of the cymbal crashes are forward, but I know I have some room in terms of level so amplitude of the crash should be tamed. Usually we listeners can take a little more cymbal than vocal, so I’m in a good position to not have to use any high frequency limiting.
Next I ask myself How deep is this thing going to cut? It’s possible to cut a deep groove all the way to the metal plate sandwitched between layers of lacquer, and we DON’T want that. This music has some pretty heavy downtuned guitars in the sides, so we’re going deep, but nowhere near the real danger zone. I do note that this is going to eat through the disc at a brisk pace though.
I look at my LPI meter — it tells me how many lines per inch are going to cut on the disc based on all my current settings. With this you can estimate the total run time to figure out about how far into the disc you’re going to go. Right now it looks like we’re going all the way in, and I don’t like it.
Metal (the music, not the substance) albums don’t fare too well in the inner diameter. I have the choice to either put my elliptical filter in, or drop the level. The elliptical will sum my low end in the sides to mono — with the result that I’ll loose some of the width in the guitars. That would be detrimental to the sound, so I choose instead to lower the level another .5 dB. Now we should finish in a friendlier place.
Time to cut. This part goes quickly — it’s the prep that takes all the time — and the result looks good! Off to plating and then pressing. I won’t hear this again unless there is a problem or I have a finished LP in my hands.
In this case, there was a problem. The test pressing comes back sounding really gritty and harsh in the top end, tinny to the max. What happened? My bet is on the quality of vinyl used: the grooves still look good under the microscope, but the surrounding vinyl looks like kitty litter. I bet it’s re-grind. The disc isn’t really even black, more like dark gray. OK, let’s call up the plant and see if there is an alternate vinyl source we can use and try again. Luckily they can still use the stampers and we don’t have to go back to square one.
We wait around for a couple more weeks, and the new test pressing comes back. This round looks a lot better! And it sounds better too; quieter overall and the high end actually resembles what I put down in the first place. I’d say we’re done, run the presses!
Now for the home test…