If you're not familiar with Softube's Modular plug-in, it's worth reading our review from June of last year. In the time since, Softube has made some modest improvements to the software. They've added free utility modules, streamlined the installation and activation workflow and—crucially—fixed an issue with iLok that was crashing Ableton Live. By and large though, Modular is basically the same plug-in now as it was back then. There's no preset management menu, moving modules is still a bit fiddly (although the addition of drag and drop helped) and screen real estate management continues to be an issue.
However, the area where Modular excels is perhaps the most important: the sound. The recreation of the Buchla 259e is no exception to this rule. In fact, it may be Softube's most realistic-sounding module yet. This is thanks in part to their clinically accurate development process. They ported the original 259e's digital components line-by-line, added the original byte-accurate wavetables from the hardware and used their analogue-modeling prowess to recreate the rest. The result is an extremely accurate reproduction. But it comes with the downside of significant CPU use. Anyone who has used Modular is familiar with this aspect of the product and likely already has a powerful computer, but the 259e expands on the processor requirements by a good margin. Some of Softube's 259e presets (especially those that incorporate multiple instances of the module) were simply too much for my i7-4770K system to handle without audio dropouts. One has to wonder what kind of supercomputer the folks at Softube are working with!
As long as I limited myself to one instance of the 259e in a given patch, I found things ran more or less smoothly. With the incredibly deep sound-sculpting capabilities provided by Buchla's original design, one instance was often more than enough. The 259e has two oscillators—one modulation oscillator with three classic waveforms and a principal oscillator that uses a combination of wavetables and a sine wavefolder to produce an immense variety of timbres. The principal oscillator allows you to choose two wavetable shapes from a list of eight choices (1-5 and A-C), which you can crossfade between using the Morph knob. The A-C wavetables are one of the trademark inventive features of the 259e as they use the internal operating system code as waveforms. When one of these is selected, the FM controls of the oscillators are repurposed as scanners that sample a portion of the 259e's memory to generate an unpredictable waveform. The result can range from digital noise to surprisingly warm synthesiser timbres. One of my favourite things to do with the 259e was to use the FM control voltage input to create rhythmic sequences that sounded like they required a team of modules to produce.
The modulation oscillator brings an additional level of depth to the module. It can be assigned to modulate any combination of pitch, waveform morph or the level of wavefolding in the principal oscillator. This can be used either as an LFO (using the low range) or an audio-rate oscillator with fixed frequency or pitch tracking options. If you're interested in oscillator sync, the 259e provides three different sync modes for the modulation oscillator: soft sync, hard sync and MIDI note sync. When you combine this with the fact that there are CV ins for every control on the module, the amount of sound design power here is pretty staggering.
The real-world Buchla 259e was able to store presets, which is a rare feature for synth modules. In conjunction with a Buchla preset manager module, this was achieved with the Remote Enable button. On the plug-in, this has been repurposed to enable incoming MIDI to act on the 259e module directly without the need for a MIDI-to-CV module. This is a nice convenience that eliminates the need for at least one patch cable (you'll still need to route a gate signal). When enabled, the principal oscillator's coarse tuning knob is recalibrated by each incoming MIDI note, which might throw some users off at first. Softube made some other smart adjustments to the original design, the most important of which allows audio and CV to be freely patched to each other.
The last thing to consider about Softube's Buchla 259e is the $99 price tag. This makes it the most expensive add-on for Modular to date, outpacing the options from Intellijel and 4ms by more than a factor of two. I can imagine that some potential customers would be hesitant to make this investment, considering that the base Modular package actually costs less. However, when you consider the Buchla licensing fees and the astronomical cost of the original, it could be considered a pretty great deal for anyone who has lusted after the Buchla sound. If you have a computer fast enough to handle it and are OK with the limitations (and somewhat slow evolution) of the Modular platform, this add-on is well worth the money.
Ease of use: 4.0