Seeking advice - making background music

Support & discussion regarding DAWs and MIDI sequencers.

Moderators: khz, MattKingUSA

Post Reply
User avatar
lintlicker
Established Member
Posts: 59
Joined: Sat Dec 03, 2011 7:51 pm

Seeking advice - making background music

Post by lintlicker »

Hi all. I am looking for some advice for a project. I am a music teacher in an elementary school. I've recently been given the green light to play music over the school's PA as the children arrive in the morning. I am able to plug in directly to the speaker system for the school. I have been plugging my cell phone into the system via 3.5mm jack and this has been working ok..... I have to keep the music at a very low volume, which means that quiet parts are inaudible.

I think the answer to my problem is that I have to compress the crap out of my tracks, but I'm not quite sure what I'm doing. Ideally, I would like all the music to be exactly the same volume, and be able to reliably know exactly how loud the output will be. If I'm too loud/obnoxious I will get my permission revoked. I hope to setup my own little "radio station" using a raspberry pi and something like audacity to prepare the music.

TL:DR - how do I use a compressor to destroy beautiful music and make it all one volume?

pepper.mitten
Established Member
Posts: 5
Joined: Fri Jan 01, 2016 8:06 pm

Re: Seeking advice - making background music

Post by pepper.mitten »

sounds like you need a player that can load a normalizer plugin. i have had mixed results with these, but i can't suggest one atm. however there are linux and android players that can do this. hopefully others have a more concrete suggestion for normalizing playlists., but when i have time i may look into it more.

gimmeapill
Established Member
Posts: 546
Joined: Thu Mar 12, 2015 8:41 am

Re: Seeking advice - making background music

Post by gimmeapill »

Hard to tell, as it really depends on your music. If you want to get all dynamic range out, and the subjective volume to be predictable you'll need more than a compressor. A limiter and/or loudness maximizer is what you should look at, like the calf multiband limiter for example. That one is best used for mastering, but you should ideally compress first per track.
Or the lazy way: upload to Youtube, Soundcloud, whatever online sharing stuff and record back - they compress the hell of everything.
Here's another online service that claims doing miracles: https://www.landr.com

User avatar
bluebell
Established Member
Posts: 1464
Joined: Sat Sep 15, 2012 11:44 am
Location: Saarland & Frankfurt, Germany

Re: Seeking advice - making background music

Post by bluebell »

CALF multiband limiter: just turn the big knob left until it's loud enough but not yet only noise.
Linux – MOTU UltraLite AVB – Qtractor – https://soundcloud.com/suedwestlicht

User avatar
Markus
Established Member
Posts: 82
Joined: Tue Jul 21, 2015 9:29 am

Re: Seeking advice - making background music

Post by Markus »

The first device should be a noise gate set to a very low threshold (~-60 to -70dB). The attack should be quite fast, release a bit slower. I expect some voice recordings and announces and the like which would result in heavy noise between words and sentences after the following compression war.

My guess is that the sound system in the school lacks of subwoofers. So you should remove everything below ~40-80Hz since this frequency range isn't audible but covers the most energy of the signal. Otherwise tracks or parts with a lot of bass would simply be quieter than others afterwards. Use the high pass of an equalizer or filter for that task with a high steepness, e.g. 36dB/octave.

I don't know anything about the audio system but most likely it will not replicate any stereo image. So I would reduce the stereo width about a half. This way hard panning of instruments will be audible in spots only fed by one channel.

Afterwards I would compensate the overall loudness changes with a quite slow broadband compressor, e.g. ~200-500ms attack and ~500-1000ms release with a ratio of ~1.5-2:1 and a threshold set to an average level so very high signals are compressed while low signals are left untouched. Don't overdo this since it might result in quite audible slow volume ramps.

After the broadband compressor use a multi band compressor with much faster timings (e.g. an attack of ~100ms in the lowest and ~30ms in the highest band and slightly slower release) at a little higher ratio to do the main compression of the signal. If you hear some "pumping" play with the timings - I would start with raising them. The thresholds would be set a bit harder than an average level like the broadband compressor so that quiet signals (like an acoustic intro compared to a death metal refrain) are just close to being left untouched.

The last step in this setup would be a lookahead multi band limiter with a lookahead of ~2-4ms and a release of ~5-10ms depending on the band (lower values for higher bands). Turn the threshold down so that it acts on mid to high signals only.

This should result in a very loud audio stream without any dynamics left. Listen carefully to every kind of audio and play with the timings in case of ugly pumping. Every dynamic-reducing device should do only part of the compression.

Good luck ^^

Edit: You should make the multi band filters fit to your signal. For example after removing the sub bass from the stream the low bands upper frequency should be raised.

User avatar
lintlicker
Established Member
Posts: 59
Joined: Sat Dec 03, 2011 7:51 pm

Re: Seeking advice - making background music

Post by lintlicker »

Thank you all so much for the help!

Post Reply