How to record Skype audio.
Sound Studio is a great, easy tool for recording your Skype audio live and editing your recordings on the spot. In this tutorial you'll learn how to get Sound Studio and Skype working together to record your conversations using two simple audio routing tools, Soundflower and LineIn, and you'll learn about some of the editing tools in Sound Studio to help you clean up and finalize your audio recording.
- Mac computer with built-in microphone and speakers
- USB headset or regular headphones
- Sound Studio application (we use version 4.2 in this tutorial)
- Skype application (we use version 5.3 in this tutorial)
- Soundflower application from Cycling74 (free)
- LineIn application from Rogue Amoeba (free)
Step 1: Routing both sides of a conversation in Skype to Sound Studio.
To record a Skype conversation means that you'll want to record both yourself talking into your mic and the person you're having a conversation with through Skype. You'll need two audio routing extensions, one to tell Sound Studio to record audio output directly from Skype and the other to tell Sound Studio to record output from your mic.
Step 2: Setting up input/output preferences to pass Skype audio to Sound Studio.
After downloading Soundflower and LineIn, you'll want to set up your sound input and output preferences in each of your applications to appropriately route audio from Skype to Sound Studio.
First, plug in your headphones or USB headset (if you don't use headphones or a headset, you're likely to get feedback with this setup). Follow these steps for each application:
Launch Soundflowerbed, which is the app that installs on your computer when you download Soundflower. Soundflowerbed appears as a flower icon in the Finder menu bar on your desktop. Click on the flower icon and under Soundflower (2ch), choose Built-in Output. Make sure that you have None (OFF) chosen under Soundflower (16ch) or you'll get some painful feedback.
Soundflower can be used as a 2-channel (2ch) or 16-channel (16ch) device. For most simple audio routing projects and particularly for this tutorial, the Soundflower (2ch) device works fine.
Go to Soundflower (2ch) > Buffer Size and choose 64, the smallest buffer size. Reducing the buffer size will reduce the amount of audio lag, which sounds like an echo, between what you say into your mic and what you hear through your headphones.
Sound Studio settings
Here you'll configure your sound preferences in Sound Studio to record input from Soundflower:
- Launch Sound Studio, then go to Sound Studio > Preferences.
- For Input, choose Soundflower (2ch).
- For Output, choose Built-in Output.
Make sure "Playthrough in to out" is not checked.
Next, you'll configure your settings in Skype to route Skype output to Soundflower:
- Launch Skype, then go to Skype > Preferences > Audio/Video.
- For Microphone, choose Soundflower (2ch).
- For Speakers, choose Soundflower (2ch).
Then, you'll configure your settings in LineIn to route your side of the Skype call to Soundflower, which in turn routes it to Sound Studio:
- Launch LineIn.
- For Input, select Built-in Input.
- For Output, select Soundflower (2ch).
When you're ready to record your call, make sure your headphones or USB headset is plugged in and then click on the "Pass Thru" button in LineIn. When you're done, turn off Pass Thru by clicking the button again.
Remember: Pass Thru on when recording, and Pass Thru off during playback, or you might get some painful feedback.
Step 3: Testing audio levels in Skype and Sound Studio.
It's always a good idea to make a test recording to check your audio levels and make sure everything is set up correctly. You can call a friend on Skype to do a test recording or use Skype's test call function that allows you to call an automated system. It'll be listed as "Skype test call" in your Skype Contacts list. If you run into any problems trying to find or use Skype test call, check out the Skype support page on making a test call.
Make your test call in Skype, then while you're on the line, switch to Sound Studio and record several seconds of conversation. Make sure you can hear yourself and the person you're talking to on Skype, and make sure Sound Studio picks up both of your voices. You'll want to speak into your mic at a normal volume and speak off-axis, or slightly to the side of your mic, so that you reduce the amount of unwanted noise.
While recording, adjust the input levels at the bottom left of the Sound Studio window to make sure they stay mostly in the green and yellow, and never go into the red.
If you start to hear stuttering or dropouts during recording, try increasing the buffer size in the Soundflowerbed application under Soundflower (2ch) > Buffer Size.
Aim for a high quality, clean recording, so that you have less editing to do later in Sound Studio.
Step 4: Editing your recording.
When you're done recording, turn off Pass Thru in the LineIn application, and then play back the file.
Sound Studio has several filters that can help you adjust overall volume levels or the volume level of a specific section of your file. If the volume levels need to be higher, use Amplify/Volume under the Filter menu to increase the gain. If you have a wide dynamic range and you want to reduce the volume difference between the louder and quieter sections, use the Dynamics Compressor. Most filters in Sound Studio provide an option to preview your edits before applying them to your audio file, so don't be afraid to try out the different filters.
About the Dynamics Compressor. The Dynamics Compressor reduces the audio level when it exceeds a certain decibel (dB) threshold. A lower threshold means more of the audio will be reduced. Peak and RMS refer to the type of compression. Peak sensing compression refers to applying compression based on peak audio levels, which may mean faster changes in gain reduction and the potential for distortion. RMS sensing compression refers to applying compression based on the average level of audio, which more closely follows your perception of loudness of the audio. The Compression Ratio is the amount of gain reduction to be applied over the threshold. The higher the ratio, the more you reduce your audio levels. Attack and Release refer to how quickly your audio levels determined by the Compression Ratio are reached.
After working on volume levels, delete any unwanted silence at the beginning of the recording and at the end by highlighting those sections and hitting the delete key.
When you're done editing the file, use the Normalize command (click on the Normalize icon in the toolbar or go to Filter > Normalize) to adjust the entire audio file to the appropriate target volume level. Set the levels to 0 dB, choose "Peak level" and calculate the amplification "Together for all tracks".
About Normalization. Peak normalization adjusts the signal level throughout the file by the same amount until the peaks reach a specified level. RMS normalization adjusts the signal level throughout the file by the same amount until the average amplitude reaches a specified level. You should use peak normalization set to 0 dB because it will adjust the audio to be as loud as possible without clipping. Clipping happens when the signal level goes beyond maximum capacity and "clips" at the peaks. You could still end up with clipping if you use RMS normalization because it adjusts the average amplitude and not the peaks, and therefore would not guarantee that all peaks will not go above the average level.
Once you're satisfied with the volume and overall sound of your recording, save your file in your desired format.
Checklist and Notes
Summary checklist for recording a Skype conversation
- Equipment you'll need: Mac computer with built-in microphone and speakers. USB headset or regular headphones. Sound Studio 4, Skype, Soundflower, and LineIn applications.
- Set up preferences in all applications to correctly route input and output.
Soundflower: 2-channel, Built-in Output, Buffer Size 64.
Sound Studio: Set Input to Soundflower (2ch) and Output to Built-in Output.
Skype: Microphone and Speakers both should be Soundflower (2ch).
LineIn: Set Input to Built-in Input and Output to Soundflower (2ch).
- Record a test call first in Sound Studio. Don't forget to turn on Pass Thru in LineIn before you record.
- In LineIn, turn off Pass Thru to play back recording. Edit recording as needed using Amplify/Volume and Dynamics Compressor filters. Use Peak Normalization with levels set to 0, calculating the amplification together for all tracks.
- Ask the person you're calling for permission to record your conversation. It's courteous, but it's also a law in some states.
- If you're having problems with the sound quality on Skype, check out this Skype support page on call quality.