Main St Audio Labs releases PR ’64 amp sim and free 6V6 Trem
Two new guitar-software releases pair a paid Princeton Reverb-inspired amp simulation with a free bias-tremolo plugin.
Main St Audio Labs has released two guitar-focused software products: Main St PR ’64, a paid amplifier simulation with a 30-day trial, and Main St 6V6 Trem, a free tremolo effect.
The developer’s GitHub release records put PR ’64’s publication at October 23, 2026, at 22:53 UTC, and 6V6 Trem v1.0.0 at October 24 at 15:27 UTC. Both fell on October 24 in Stockholm.
PR ’64: an amp, reverb and tremolo package
Main St describes PR ’64 as a component-level simulation of a 1964 blackface Princeton Reverb. Its feature list combines amplifier modelling, spring reverb, bias tremolo and a cabinet section, alongside a tuner and presets.
The licence costs US$14 as a one-time payment. The developer offers 30 days with all features available; a licence is required to keep the amp working after that trial. Main St is an independent developer, not affiliated with Fender.
6V6 Trem: a separate free effect
Main St 6V6 Trem takes the bias-tremolo concept into a dedicated effect with Smooth and Deep modes. All functions are available free, without a time limit. An optional support key removes the brief welcome window; it is not required to unlock the effect.
Both products offer VST3 for Windows, macOS and Linux, plus AU on macOS. PR ’64 also includes standalone applications; 6V6 Trem requires a compatible host and has no standalone version.
The stated minimums are 64-bit Windows 10, macOS 10.13 with Intel or Apple Silicon support, and x86_64 Linux with glibc 2.35. These are the developer’s specifications, not results from a GuitarGangsters installation or listening test.
For the hardware background, explore our Fender Princeton Reverb guide.
Original AI-assisted conceptual illustration for GuitarGangsters. The abstract waveform is decorative, not measured audio data; this is not a product-interface screenshot.