Andreas, I want to thank you for bringing this up. This is very important work. Interest in open-source audio is going to grow DRAMATICALLY within the pro audio industry in the next year or so, and it will be quickly squelched if basic principles ( like smooth gain adjustments given a wide range of inputs ) are ignored. Personally I find many of the plugins, particularly the filters and compressor/gates, to be nearly unusable and certainly not in the same class as commercial offerings. Why should this be true? Commercial developers have the advantages of full-time development, years of focused experience, and expensive test equipment. Open-source developers have the advantage of peer review. I hope that your study is just the first in a series of highly critical looks at the open-source offerings, and that it results in a definition and refinement of the "best practices" that are already known by professional developers. For our part, Harrison has taken an interest in Ardour and has actively guided development towards professional needs for the last 6 months or so. You can expect to see more industry involvement as the benefits of "Free sofware" become obvious to the pro audio world. 10 years of proprietary development has resulted in the stagnation of our industry. For example, there are certain limitations: bit depth, file compatibility, and inter-app communication, that cannot be lifted given the current audio software business environment. These limitations are NOT imposed by Free software like Ardour. Open Source and/or Free software is the only avenue open for true innovation and improvement in sound quality. Please continue to look critically at the available plugins, and continue to raise these issues before there is an influx of professional interest. Open-source plugins may never sound as good as the best commercial offerings ( *cough* Harrison *cough* ), but they shouldn't be allowed to sound BAD, given the wealth of knowledge available in the LAD group. -Ben Loftis www.harrisonconsoles.com