You are granted a broad royalty-free license for every sample that you download from Splice Sounds. This means you can use, reuse, remix, and otherwise modify downloaded samples for use in any of your productions, including commercial projects.
The following is from our terms of service:
c. License. Samples are licensed, not sold, to you. Subject to Section 7(d) below, you are granted a non-exclusive, non-transferable, perpetual right to use Samples you access through Splice Sounds in combination with other sounds in music productions to create derivative works. This means that, subject to Section 7.d, you may modify, reproduce, publicly perform, distribute, transmit, communicate to the public and otherwise use Samples, including for commercial purposes.
d. License Restrictions. You may not (i) use the Samples in isolation as sound effects or as loops, (ii) use Samples in a manner competitive to Company or its licensors, or (iii), sell, loan, share, lend, broadcast, rent, lease, assign, distribute, or transfer all of the Samples to a third party except as incorporated into a derivative music production.
For a detailed description of the license terms, click here.