Regardless of whether you think playing back audio at 96kHz sounds better than 44.1kHz, recording at 96kHz can improve some amp sims’ sound—specifically, those without an oversampling option. This is because the harmonics generated by distortion can interact with a digital system’s clock frequency and create audible artifacts that usually add a “wooliness” to the sound. Higher sampling rates, however, can produce a clearer sound.
But recording at a higher sample rate isn’t always practical, because it stresses your computer more. This can cause reduced track counts, or less stable operation. Fortunately, the workaround may be simple. Some amp sims have an internal oversampling option. Essentially, the sim itself runs at a higher sample rate than the project hosting it. So check the sim’s preferences for an Oversampling, High Resolution, or Higher CPU Consumption setting. (Avoid power-saving “eco” options. For more information, see “Checked Your Sim Preferences Lately?” in the July 2014 Guitar Player).
Fig. 1—The site src.infinitewave.ca shows sample rate conversion quality for all major programs. Closer to a single curved line is better (Apple QuickTime Pro 7.6.6).
If your sim doesn’t have these options, there’s a workaround.
• Record your guitar track as you normally would in the 44.1kHz project, using your amp sim and preset of choice.
• After recording your part, save the amp sim preset.
• Regardless of where you started recording your guitar part, extend its beginning—even if it’s silence—to the project start. This may require dragging the clip start to the beginning, or inserting silence.
• Export the dry guitar track without processing by the sim at 96kHz, assuming your host program has quality sample-rate conversion (Fig. 1). Otherwise, export at 44.1 kHz.
• Open a new project set to 96kHz, and import your guitar part starting at the project beginning. If you couldn’t export at 96kHz, some hosts will convert when importing. Otherwise, do sample-rate conversion in a separate program (such as Audacity) prior to importing.
• Load the amp sim and its preset.
• Render (bounce) the file with the amp sim sound, and then export the processed file at 44.1kHz.
Now, you have a 44.1kHz file to import into your 44.1kHz project, starting at the project beginning. It’s counterintuitive that you’ll retain the 96kHz project’s higher quality at 44.1kHz, but you’ve “freezedried” the higher-quality sound as audio that can be reproduced at a 44.1kHz sample rate. You’re no longer using an amp sim to create the audio.
Please note that I’m not a “cork-sniffer” audio guy who insists on cables made from unobtainium. Depending on the amp sim, the effect will be sufficiently obvious that anyone will notice it. It’s not subtle.
So, at least when recording, higher sample rates can be useful (this same technique can also apply to virtual instruments and some dynamics processors). But do they make a difference on playback? I’ll let others argue about that one...
Craig Anderton has played on or produced more than 20 major label releases, mastered hundreds of tracks, and written dozens of books. Check out some of his latest music at youtube.com/thecraiganderton.