Monday, April 12, 2010

Guide to digitising vinyl

Here's a handy guide from Soul Sides, entitled, The Cavern Productions/Soul Sides Guide to Digitising Vinyl.


Prepared by Brendan Irvine-Broque (for Cavern Productions) and Oliver Wang (for Soul-Sides.com)

Before you start to build a vinyl digitizing system, remember how sound signal chains work. Every sound, whether it’s coming from a singer’s voice or a groove from one of your LPs, has an origin, and passes through a number of different physical and electric stages before it becomes the 1s and 0s that reside on your hard drive.

This is the long version:
1) The physical grooves of a record
2) The turntable, which spins the record at a theoretically constant speed, and isolates it from any internal or external vibrations.
3) The tiny needle that follows the grooves
4) The cantilever system that acts as a suspension system for the needle as it is affected by the record’s grooves
5) The tonearm that stablizes the needle and keeps it in the grooves
6) The wiring inside the tonearm, and the wiring coming out of the turntable, which carries a very weak signal through unbalanced cables into the phono preamp.
7) The phono preamp, which uses the standardized RIAA equalization curve to boost bass frequencies that cannot be represented by grooves on a vinyl record at high amplitude.
8. The cables that connect the phono preamp to the Analog/Digital Converter (ADC)
9) The ADC itself – its dynamic range, accuracy, and clocking.
10) A computer software program that then saves that information into a sound file (AIFF, WAV, MP3, etc.)

This is the short(er) version:
1) The record itself
2) Stylus + cartridge (can be upgraded separately)
3) Turntable + tonearm (can be upgraded separately)
4) Phono preamp (either stand-alone or built into a stereo receiver or DJ mixer)
5) ADC (either stand-alone or your computer soundcard)
6) Computer software
For each part of this chain, your decisions will impact the quality of sound at the back end.

Let’s get the simplest things out of the way first: computer software.
BIB says: Audacity is the most popular by a long shot, though I find its user interface to be confusing and inefficient. I recommend the inexpensive, yet very worthwhile Peak Express, made by Bias Inc. It’s been around for over a decade, and the professional version is used in many mastering studios. At $29, it’s a steal, and will save you hours of time.
OW says: I’ve always liked Sound Studio 3 for the Mac. Simple, easy to use, but also powerful. $60.

Now here comes the more complicated parts…
The simplest way to digitize vinyl is to buy a generic audio cable as the link between your preamp and ADC. If you’re already a DJ, this likely means running a cheap (less than $5) cable from your DJ mixer to your computer soundcard. Assuming that mixer is connected to something like a 1200 that you already own, this will almost assuredly sound better than the Numark or Crosley USB turntables that seem to be popping up everywhere these days.
Note: It may be tempting to buy one of these cheap, plastic USB turntables since they combine #2-5 into a single machine. And frankly, if you just want to digitize records and you don’t care that much about how the final product sounds, this may be the way to go and you can stop reading now.

For those who want a higher level of sound quality, keep reading. The basic principal of capturing sound is to ALWAYS start at the origin and work from there. There is no need to spend any extra money on a special, high-end ADC if there’s a weak link in the chain PRIOR to getting there. That’s why the kind of cartridge, turntable, and preamp you use are relevant.

To put it another way: you can’t get gold from lead; you need to start off with gold (the record you want to digitize) and hope the rest of your chain doesn’t tarnish the sound too much.
If you want to get serious, start at the beginning.

1) Are your records clean? There are all kinds of options out there, from robust vacuum designs like the VPI 16.5 to Groov Glide, to DIY designs involving ultrasonic cleaners. This may sound excessive, but remember: most of your records are at least a decade old, if not 50, and if you bought them used, who knows where they’ve been and what they’ve been exposed to? Dirty records = dirty sound. So make sure your records are as clean as you can get them before a stylus ever gets into those grooves.

2) Stylus/cartridge. These are a matter of personal choice. There may be objective quality differences between brands and models, but ultimately, it comes down to what’s pleasing to your own ears and people will have their subjective preferences.

BIB: My personal recommendation is Ortofon Concorde style cartridges – I use the Nightclubs for archiving, and have the elliptical (E) styli for LPs and the spherical (S) styli for 45s.

OW: I would second the Nightclub E but, as BIB notes, you may want to change styli (same cart, different needle) for 45s. In my experience, a “loud” 45 played with an E stylus is prone to bad distortion. I use my Nightclub to digitize LPs but often switch to a Shure White Label for 45s (I don’t own a separate S stylus for the Nightclub).

3) Turntables.
BIB: Technics 1200s are the kings. If you’re willing to spend $200 or more, it’s absurd to buy anything else. The “warmth” that audiophiles talk about getting from other turntables is nothing but resonance that reinforces midrange frequencies in a way that pleases the ear, but isn’t accurate. Like EVERYTHING record related, the Japanese have the game on lock and Technics are no exception.
OW: I think 1200s are a perfectly good choice and if you’re a DJ, you already know this. But if you’re NOT a DJ? I think there are other options, especially if you’re willing to spend time on Craigslist or eBay or browsing thrift stores and swap meets. There’s many good medium/high-end consumer turntables made in the ‘70s and ‘80s to be found under $200. This is a great research resource.

Ultimately, if you want to take the guessing game out of it? Look for a used 1200 under $250. Can’t go wrong with that. Me though? I’m fiending for one of these.

4) Preamps.
Preamps pose a unique challenge in the digitizing realm. Professional grade, stand-alone phono preamps are practically nonexistent and instead, you’re often left with either overpriced audiophile models and cheap, high-school-electronics-class designs.
There are some wonderful phono preamps built into some home stereo receivers from the 1970s, but these come with their own problems having to do with crosstalk and voltage, because there are so many other components within an analog stereo receiver (AM/FM radio, inputs, 50 watt speaker amplifiers, etc.). Current, analog DJ mixers are likely the best choice for anyone serious – particularly because they offer XLR or TRS balanced outputs, which keeps the noise floor low and dynamic range high.

BIB: I personally use an Allen & Heath Xone 02, just for the phono section, but only because it’s the best thing I’ve found so far. I’m hoping to build out a balanced Bozak (link) phono preamp sometime this year – they were the gold standard for design in DJ mixers for discos of the 70s and 80s, and are revered for their phono preamps.

I really wish that I could give a more solid recommendation for a dedicated phono pre, but the only phono pre I’m remotely interested in is a rackmount unit that the homie Thes One had custom-built by Manley.

OW: I used to use my Rane TTM56 as a preamp and from what I’ve heard, Rane builds very good preamps into their DJ mixers. But when I decided to separate my digitizing set-up from my DJ set-up, I needed to put the Rane back and look into a stand-alone preamp. The overwhelming recommendation I got was for the Radial J33 (which Thes One also uses when he’s not running sound through his custom Manley pre).

I’ve been happy with it so far and what’s nice is that you can plug headphones into it and you’re likely to get better sound from that than a stock computer soundcard (you can’t adjust volume though). I’ve had some people recommend the Rolls V29; it’s inexpensive but I’ve never test-driven one.

4.5) Cables.
Remember that your sound signal chain has to travel down wiring and the quality of wire matters as much as every other part of the chain.
BIB: My absolute highest recommendation goes to Redco Audio, who lets you design your own cables at very affordable prices, down to the length, connector style, and cable quality. I probably have over 50 cables from them, and know many studios who count on them regularly.

5) ADC.
Unlike preamp choices, the consumer options here may seem staggering but don’t be fooled. The vast majority of ADCs on the market are not worth your $200. Why? Because even though they most often have the exact same chipset that’s used in Protools HD systems, most are fraught with the exact same problems that plague your laptop’s soundcard – unstable and insufficient voltage rails, interference, and shoddy manufacturing. Avoid M-Audio, Tascam, MOTU, or others unless you plan on having it modded.

BIB: There are two companies making quality, affordable audio interfaces that sound great – Apogee Digital and Echo Audio. I personally use the Duet, and it’s wonderful, stable, and is truly the best you can find for less than a grand (at which point I’d start looking at RME, Lynx, and other Apogee products).

OW: I bought a Duet, partially on BIB’s recommendation, and have been very happy with it. The versatility is excellent – you have multiple ways to cable it (XLR, 1/4”) and the jog wheel lets you adjust both input levels and headphone volume. They’re not cheap – even used, expect to shell out around $250-350 – but if you’re serious about stepping up your ADC, it’s worth the added cost.

In conclusion:
The cost-differences here are dramatic depending on how you want to play it. An all-in-one USB turntable will run you about $100 or less. The set-ups both of us use will set you back at least $700-1000+. If you are going to trick it out, just remember: the strength of the digitizing chain is a linear process. You have to make sure your starting components are strong before worrying about the end; investing in a Duet or Echo would be one of your last purchases, not your first.

2 comments:

deleted said...

Random Question - but whats wrong with using a decent turntable, plugged into a Serato SL3, and pressing record.

Seems like the simplest method of doing while still using decent equipment. Cuts out the need for a preamp (as the SL3 has one in it etc). and is decent quality hardware (made by rane). Is there a downside to this?

Then just tidy up the recording (.aiff) in a editing programme and save as 320kb mp3?

Peter McLennan said...

fair comment - if you've got Serato, sound like a good way to do it. I suspect this is written for non-Serato users, ie music collectors as opposed to DJs.