Trilogy was introduced in 2002 by Spectrasonics and, since then, it has become the tool of choice of many musicians when it comes to sampled bass guitars. I first found it in 2010 and since then I have been unable to find any other tool that gives me as many choices and possibilities and Trilogy does. I have never found compatibility issues, and that's a lot to say since I've used trilogy on six different hardware setups and for many different endeavors. There are no unnecessary steps when it comes to installation: you just place th 3gb samples file wherever you choose and run the software. The only issue is that the program comes, originally, in a set of CDs, so installation may take a while. The simple interface and ready-to-go general quality of the software makes up for it, though.
The software is really stable, and to be fair the only crashes I experienced while working with Trilogy were due to issues with Nuendo or overloading my sound card. As said before, I've been using it for four years and I've never had the need to look for other solution when it comes to sampled bass. Trilogy provides you with an incredible amount of patches to choose from, broken down into easily identifiable categories (that mostly rely on style, so that makes choices even faster). As it usually happens with this type of software, there is an overabundance of preset synth instruments, and that makes it a little harder to find the correct sound when working with certain types of electronic music.
As instruments are subcategorized by articulation or general dynamic range, you will usually have to load more than one instance of Trilogy, and eventually that hinders performance.
I particularly like the straightforward and visual appeal of Trilogy. You can easily create your own sound, either from scratch (though that's not what the program is designed for so that may be a little hard to pull off) or basing it on one of the thousands that the systems comes with by default. The presets include different types of bass (electric, standard acoustic, upright, synth) and it features an organization system with categories such as ''Old school'', ''Modern'', etc. that make it really easy to focus your search according to the type of music you are working with. The preset usually come in two different sound schemes, caled A and B, and you can adjust them individually.
The versatility of Trilogy is also an important point. I've worked in heavy metal, soft rock, jazz, and multiple other projects, using Trilogy for sketches as well as for final versions, always with excellent results.
Spectrasonics Trilogy is a VST software plugin instrument that is a total solution for all bass sounds, both realistic and synth. It includes thousands of professional bass patches, with easily modifiable settings and parameters. For realistic basses, it includes multiple bass guitars (including upright bass), multiple articulations and modes (including slides, gliss, hammer-on's, harmonics, trills, and noises), and much more. Originally, this software is installed from a set of cd's (not even DVD's), so it can take awhile to set up. It comes in VST and RTAS format, but it does not come in a DirectX plugin format (which is what I prefer when working in Cakewalk SONAR). It includes gigabytes of high-quality, professional sounds, and for being a relatively pricey produce (over $300), the quality certainly shows, even though the simplistic interface.
Trilogy excels in simplicity, flexibility, and all of the sounds are generally great. With a massive patch system, you can easily browse and find any bass sound that you are looking for, whether it be a real bass or a synth bass. It also lets you edit the major parameters of the sound, such as envelope, filters, LFO, velocity curves, slide/porto, and much more. Most of the patches come in the form of two main sounds, A and B, and you can adjust the parameters and volume of the two sounds individually, or you can adjust them simultaneously.
It is very easy to quickly find a great sound, and then simply fine tune some of the parameters (mainly envelope) to your personal needs. It is possible to make new sounds from scratch, using the Trilogy sound library, but this is not necessary and for the most part, I never do this. If you want a synth where you can create sounds from scratch, this isn't the best tool for that job.
Overall, the Trilogy is a wonderful solution for all bass needs. It may be a legacy product now, but this is a product worth finding!