Downloading Warbler 1.2 for Mac from the developer's website was possible when we last checked. We cannot confirm if there is a free download of this app available. We recommend checking the downloaded files with any free antivirus. Warbler for Mac lies within Audio & Video Tools, more precisely Editors & Converters. This Mac application is an intellectual property of Expert Sleepers. The most popular version among the program users is 1.1.
From the developer:
Warbler is at heart a vibrato effect, with additional controls that allow chorus/flange/delay type effects, as well as quite unusual hybrid sounds that aren't easily categorised. The vibrato depth ranges from subtle modulations to extreme pitch effects. The vibrato LFO (low frequency oscillator) can be set from 0Hz to 5kHz and is controlled by 3 knobs to allow accurate control over the whole range.
You may want to check out more software for Mac, such as WAVManager or Aiseesoft FLV Converter Suite for Mac, which might be similar to Warbler.