If you, like me, have a sizable vinyl record collection, then at some point you may want to make digital copies of them ("vinyl rips") so you can play them out or enjoy them on your phone or computer. I've done this a fair amount of times -- probably about a hundred records -- and let me tell you: there is a lot that can go wrong and affect the quality of your transfers!

A friend of mine recently asked for some tips on vinyl ripping his own collection, so the following started as a comment on his Facebook post. However, after posting, I realized that some of this knowledge may not be very widely known, so I thought I would polish it up and make a blog post of it!

This is not a step-by-step guide for beginners; I am assuming you already have your turntable, software, and audio setup worked out. (I am also kind of assuming you are an electronic music DJ, but this advice should work for anyone.) So if you want your hand held, look elsewhere! This post is more about the little things you want to think about before you hit Record:

1. Check your pitch calibration using the dots on the side of the platter and the red light. You want to make sure that the '0' on the pitch control corresponds with exactly 33 or 45 RPM. This is especially important for accurate BPM readings, beatgridding, and beatmatching. If you don't know how to do this, here is a good guide.
   
   
2. It helps to have two turntables: one for recording (deck 1), and one for prepping the next disc you want to record (deck 2).
   
   
3. Do a quick cleaning on the disc right before you record to reduce dust. A wet cleaning would be best; I usually do this on deck 2 while deck 1 records. You can put a fan on it so it dries fast. This way all you will have to do on the disc you are recording is a quick dusting or dry clean, mainly to catch dust from the slipmat (if you use those) or the rubber mat. 
   
   
4. Use a fresh needle; worn needles will impact sound quality!
   
   
5. Use a good preamp. it will make a huge difference! The preamps on my Pioneer XDJ controller are complete ass. Preamps are usually kind of expensive, but I've had good luck with some of the cheap Chinese units you can get off Amazon. (Fosi Audio makes a pretty good hybrid tube/solid state preamp that isn't too expensive.)
   
   
6. If you're using a digital recorder, it can be annoying to match up generically-named audio files to their original disc. So, on a notepad, or in your phone's notes, write down the file name on the recorder next to the record name or Discogs ID. Then, it will be easy to match which file goes to each disc, and then you can add other metadata later. (And be sure to hit the 'track cut' button, or hit stop and then record again!)
   
   
7. For electronic music: even with the Technics direct drive, even if you calibrate it with the red light and the dots, there is very slight pitch wobble and BPM won't usually be a perfect round number. I believe this is a symptom of analog being analog both on your turntable and on the record cutter that produced the original mother that your disc is stamped from. This makes accurate BPM readings and setting up beatgrids on DJ software a much bigger pain in the ass than you might be used to with digital files. Be careful playing these out with SYNC enabled!
   
   
8. If possible, you should record in 32-bit float format. This way it is practically impossible to clip the recording! Then you can set audio levels in post and bounce the final cut to 16-bit. 32-bit float has such a wide dynamic range that clipping is never going to happen. (That said, I don't think this benefits sound quality very much if at all; but there are those who would argue that you should record in at least 24-bit. My suspicion is that this is an audiophile's old wives' tale. My own research indicates that vinyl's dynamic range is equivalent to something closer to 12-bit digital audio.)
   
   
9. Recording in anything above 44.1khz is probably overkill -- but if you want a higher sample rate do an integer multiple like 88.2khz. This way, you can minimize the chances of downsampling adding weird quantization artifacts. Again, there are those who would argue you should record in the highest sample rate you can, but in my opinion this more audiophile cargo-culting. (The exception here is if you plan on doing weird stuff to the resulting audio file, like pitching it down, sampling, or running it through an FX chain. In those cases a higher sample rate would be better.)
   
   
10. Set your needle weight to something a little higher than usual, so that you can minimize skips.
    
    
11. Make sure the needle is as close to perpendicular to the disc as possible; a slanted needle will produce stereo audio levels that are slightly higher in one channel than the other. If possible you will want to verify this with level meters before getting started.

I recently ran into the following error when adding some indices to a PostgreSQL database from within an Alembic migration:

CREATE INDEX CONCURRENTLY cannot run inside a transaction block

def upgrade():
    with op.get_context().autocommit_block():
        op.execute("ALTER TYPE mood ADD VALUE 'soso'")

my_column HSTORE DEFAULT '' NOT NULL

t.hstore :my_column, default: {}

sa.Column('my_column', HSTORE(), nullable=False, server_default=sa.text("''")),

from sqlalchemy.dialects.postgresql import HSTORE
from sqlalchemy.ext.mutable import MutableDict

class Item(db.Model):
    my_column = db.Column(MutableDict.as_mutable(HSTORE), nullable=False, default={}, server_default='')

    def __init__(self, **kwargs):
        kwargs.setdefault('my_column', {})
        super(Item, self).__init__(**kwargs)