Mastering for commercial releases (EQ and all that)

I assume I can use whatever sounds good on online services such as Spotify, but what if I want to burn my music a CD, or even go as far as sending it to a vinyl pressing plant? How do I need to prepare my tracks for such formats, if needed? I would prefer if you could separate each answer from each other, and if possible, give a step for step guide. Thanks in advance!

I know you’re expecting a list of filters and effects, but without question the first thing you need is a good sound system so you can hear what you’re doing. Or good headphones. Without one of those (or both) you really are just doing busy-work. “It sounds OK on my computer speakers” doesn’t take you far when your audience explodes.

If you’ve done a good job recording in a quiet, echo-free environment then the easy part is done. The difference between commercial releases and home recording is likely to be loudness. You’ll find immediately that you can’t crank up the volume without the high peaks becoming damaged, and unless you crank up the volume, you don’t sound anything like the other similar performers. The trick is gently squeezing the peaks and high volume points so there’s room for everything else to come up. This is what volume limiters and compressors do (not to be confused with data compression like in MP3).

This is a picture of the blue waves I took starting with a plain performance capture and applying two increasingly stiff compressions. Note everything gets bigger (louder) and more even.

That was Chris’s Compressor.

Audacity has building block compressor and limiters.
And other custom tools.

Some classical performances don’t do that. They just lay the opera down as it’s sung. But if you’re a pop artist, that’s probably not going to fly. Anyone who pulls down your work on iTunes is going to expect it to compete with all the other tunes on their Personal Listening Device.

And we warn people constantly, Never do production in MP3. Use WAV until you get your masters, then make MP3 if you want. You can always go down to a lesser quality, but you can’t come back up.


Here they are:

Effect > Hard Limiter
Effect > Leveler

For each of those Effects, you need to apply the effect and critically listen to what happened. It’s not “Push This Button for a Master.”

When you start punching up your volume you may find that your formerly quiet, well-behaved recording isn’t so quiet and well-behaved any more. If you have any echo or background noise in your show, it will come right up and say hello. This kills home recordists way before anything else.

Did you post any of your work-in-progress anywhere we can listen to it? We can make a lot more accurate recommendations if we know what we’re dealing with. If possible post the work with no effects or filters. You can’t get much more than two seconds on the forum, so you’ll need one of the file posting services.

Or your web site if you have one.


I assume I can use whatever sounds good…

That’s basically it! The main goal is to have someone with “fresh ears” or “different ears” take over from the mixing engineer for any final touches to the sound, and to make sure all of the songs on an album sound good when played together in sequence.

And generally, you are going to use the same best-sounding master you can make no matter what the distribution format. You might be able to do some tweaks so that a low-bitrate streaming MP3 sounds a little better, but it’s the job of the compression algorithm to make the best of what you feed it. And, you want to put your effort into the good-sounding stuff, not the stuff that’s going to sound like crap anyway.

There may also be format requirements or recommendations. (i.e. CDs should be 44.1kHz/16-bit, and iTunes should be AAC, etc.). But, you really have to check with wherever you are sending it. Most download services will do a conversion if you upload a format that’s not standard for them, so it shouldn’t be too critical. But, but in any case, you should use a high-quality format (or high bitrate, if compressed) since they may transcode and degrade it.

A CD pressing plant may require a DDP file. The DDP file has everything the pressing house needs. If you are having CDs burned, an ISO file should be acceptable, and a master CD might even be acceptable.

I have no idea if there are any standards for vinyl. It’s a “specialty item” and the pressing house is is likely willing to use whatever format you give them. (Of course, you are going to get more respect if you send them a high-resolution format.) You’d probably have to give them instructions for what goes on each side, and you might have to ask about their time-limit for each side.

There is also a trend in to make your recording “louder than everybody else” by using tons of compression & limiting. ([u]Loudness War[/u]) “Loudness” is the responsibility of the mastering engineer. Achieving the loudness you find on commercial CDs is difficult for amateurs to do at home without introducing unacceptable amounts of distortion. And, sometimes the pros go-ahead and introduce distortion (clipping).

iTunes Radio is countering the loudness wars by volume-adjusting everything before streaming. So for iTunes Radio, you’d be destroying all of the dynamics for nothing.

A vinyl or high-resolution version may be less dynamically compressed, but that’s up to you (or the producer)… There’s no technical reason for using more dynamic compression on a CD or MP3. It’s just a matter of marketing and the loudness wars. In fact vinyl has less dynamic range than CDs or MP3s, but again for marketing reasons you might want to have a different more dynamic master.

I have some good links on mastering -
[u]What’s This Mastering Business Anyway?[/u] (Moulton Labs).
[u]Tips & Tricks For Mastering[/u] (Moulton Labs).
[u]Mastering With Ozone[/u] (Izotope).
[u]Mastered For iTunes[/u] (Apple).
[u]Details of a particular mastering job[/u] (REAPER forum).

iTunes Radio is countering the loudness wars by volume-adjusting everything before streaming.

Taking a page from Broadcast Radio.


Still wouldn’t mind hearing some of the work…


Sort-of, but better! Radio stations use dynamic compression, again to make it constantly loud. iTunes Radio uses [u]SoundCheck[/u], or something similar to SoundCheck or ReplayGain, to adjust the volume of the entire file equally, which preserves the dynamic range.

On average, SoundCheck and ReplayGain tend make loud songs quieter. That’s because most music is normalized, so you can’t boost the loudness linearly without distortion. Since that’s also true of quiet-sounding songs, the only way to match the loudness of a bunch of songs it to reduce the volume of the loud-sounding songs. The advantage is that dynamic music remains dynamic (the loud parts of a song remain loud and the quiet parts remain quiet), and no further damage is done to dynamically compressed songs.

I would not have thought Apple would allow the clients to make their own AAC files, but I guess it makes perfect sense. If you created your own AAC posting, you can’t complain about it. Or you can, but everybody will laugh at you.

A friend of mine just had his second album post on iTunes. I need to ask how they did it. He gave me physical CDs, so I never went up and looked. He had a very good producer, so maybe she plowed through all the technology.

I’m not a fan of SoundCheck. Because of its throttling nature, it makes talk shows even harder to hear when I’m walking around traffic. I look down and the iPod speaker volume thermometer is cranked all the way up.

“I need more Zot! (technical term)”


Not my original song, though!

Terrific. Thanks for point to the posting. Whose song is it originally?


His name is David Nelson, from Inverness, Scotland. Not very famous, but he’s done some pretty nice music.
I found him on Youtube where he demonstrated a pretty elaborate home-made record lathe. His Youtube and Soundcloud account names are both “pentlandsound”.

I don’t undestand where is the interest is in doing a vinyl from a digital sound capture :frowning:

You’d be surprised - there’s several companies doing that (given the current renaissance of vinyl among the young) :sunglasses:

I don’t see the point either, as I don’t believe in “vinyl warmth” (which mostly comes from distortion from the cart and the pre-amp imvho) - but if that’s what folks want … :confused:


And they’re right :smiley: