Why is the India LP taking so long?
First, I’m sorry if this is a bit mundane. It’ll be boring to most, but maybe interesting to some.
As most who read this know, I’m in the process of re-recording all of my Early ISKCON records to digital. Part of this process includes removing all the pops, clicks and crackles that are associated with poorly cared for vinyl.
My second entry is Acyutananda Swami’s India LP. I talk quite a lot about it here. To sum up, because of the weirdness in the pressing of this particular edition of the India LP, there are tons of pops and clicks.
Most of these come not from my copy of the record, but because this edition was recorded from a very crappy quality of the first pressing of the record (rather than the original master tapes).
Because of this, the record sounds muddy (which I can’t really fix) and the pops and clicks aren’t exactly your normal pops and clicks.
After capturing the record to wav file, I “clean” up the songs using a Linux program called Gnome Wave Cleaner (GWC). The software is free and works pretty well. The process is very slow (it takes over an hour to cover about a minute of music – a 40 minute album will take around 50 hours).
But it’s worth it. I’ll show you what I do.
Here is the 7th track, Gopinatha. I’m around a minute and a half into this track. I isolate about 15 seconds of music and have the program automatically mark where the pops and clicks might be. That’s what’s marked in red.
Zooming into the 15 seconds, you’ll see that there are 238 markings. Most of these are false positives marked because of the crappy quality of the original recording. Some, however are real.
Listen to this 15 second sample before cleaning… (it’s very noticeable when you’re listening via headphones)
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From here, I’ll isolate about a three second segment and focus on that. There are many markings, but only three or four pops that can be heard.
This program offers to automatically correct these clicks and sometimes that works. However, due to the low quality of the recording, especially when Acyutananda Swami is singing, it not only removes the pop, but also a bit too much of the music, causing a weird drop out in sound.
To prevent this, I do things semi-automatically.
Below (on the left) is a small pop. A pop is very quick. Most pops last about .0005 of a second. They’re so foreign that they stick out, but really, they’re short. The amount of time in the screen caps below is .01 of a second. Often, I’ll zoom in farther to .025 of a second. On the right is the same segment without the pop.
(Click on the pictures to see what I’m talking about.)
On GWC, there’s a tool called LSAR Signal Estimation. Basically, this estimates where the waveform should be and moves it there automatically. You have to find the pop/click yourself though. Sometimes they’re easy to spot, other times, not really.
The next example shows a much louder and longer pop. It’s about double the length of the pop above. The LSAR tool takes care of it as well.
While the tool “automatically” corrects this, you have to find it yourself. Sometimes they are marked as pops, sometimes they’re not. Sometimes they’re really noticeable, other times, they’re buried.
Sometimes one pop is actually two. These pops are only .01 of a second apart. Taking care of each, one at a time, gets rid of the pop.
And sometimes you just can’t get rid of the pops. This 15 second segment is a great example because while I could get rid of most of the pops, there’s still one or two in there that were so buried it was impossible (for me) to get rid of them without damaging the music. Strangely enough, it sounded better with the pop than without. This is a rarity, but it happens.
So take a listen to the cleaned up version, see if you can spot the rogue pop or two.
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I’ll do my best to get this finished up as soon as I can. There’s about six or seven more hours of work that will have to go into it, so perhaps by this weekend or early next week we’ll see something.
I just wanted to share this fun experience. Haribol!
