Get Serious with the G-Storm Electro SH5-VCF: An Eurorack Adaptation of the Roland SH-5 Dual Filter and Mixer

The G-Storm Electro SH5-VCF is an analog Eurorack module that has been adapted from the Roland SH-5 mixer and dual filter. Unlike filters built with chips, the SH5-VCF uses all discrete components and op-amps to provide a unique filter experience. The module features a voltage-controlled filter with a separate bandpass filter that has a proprietary voltage-controlled feedback path. It also comes with a four-channel mixer that has individual fader pots and filter routing switches.

The SH5-VCF's voltage-controlled filter is composed of one high pass and one low pass circuit in series. It allows the user to choose a high pass, low pass, or bandpass configuration using the VCF Select switch. The low pass circuit's resonance can self-oscillate, but the v/oct keyboard tracking is only about three octaves at its best due to the lack of temperature compensation.

The SH5-VCF also features a dedicated bandpass filter that has a discrete circuit that is separate from the VCF. It has a buffered output jack that is not available on the original design. The BPF Level attenuator only affects the main output.

The four-channel mixer has individual fader pots and filter routing switches that allow each audio line to be sent to either the VCF, BPF, or both VCF and BPF. The mixer is an excellent tool for those who prefer to perform live with their modular synth setups.

The SH5-VCF comes with three CV modulation options, each with different behavior. CV1 has inverting and non-inverting behavior, CV2 has non-inverting behavior for both filters, and inverting behavior available to VCF only, and KB is a non-inverting V/OCT Keyboard Tracking control available to both the VCF and BPF. It is important to note that the module requires startup voltages on the low end to avoid audible thump, which may lead to sub-frequency audio seepage. To achieve the best filter experience, it is recommended to follow the filter with a VCA and use a post-filter VCA to gate the filter.

However, the SH5-VCF is currently unavailable due to parts shortage, and interested buyers may have to wait until 2024 to acquire the module. Overall, the SH5-VCF is an excellent choice for those who are looking for a unique analog filter experience.

Example Usage

If you're new to eurorack and looking for a filter module that offers a lot of versatility, the G-Storm Electro SH5-VCF is a great option. With its four audio signal inputs and individual fader pots, this module is easy to use and allows you to experiment with different filter routings. Plus, the addition of CV inputs for each filter frequency cutoff allows you to modulate the sound in interesting ways. Just keep in mind that this module should be followed by a VCA to avoid any audible thumping and sub-frequency audio seepage. If you're looking for a recommendation, the G-Storm Electro 2xVCA is a great choice!

An intermediate-level usage example for the G-Storm Electro SH5-VCF would be to use it to create a complex filter sweep. To do this, you could patch an LFO into the CV1 input and set it to a slow rate. Then, take a sawtooth wave from your oscillator and send it to the first audio input fader. Set the filter routing switch to send this signal to both the VCF and BPF, and adjust the fader rates and resonance levels to create interesting harmonics. Finally, you could use another LFO or envelope generator to modulate the BPF Level attenuator, creating an animated and evolving sound. This setup would push the limits of the SH5-VCF's flexibility while also showcasing its unique tonal character.

Further Thoughts

The G-Storm Electro SH5-VCF provides a powerful mixing and filtering solution for Eurorack enthusiasts. For example, it can be used to create complex multi-layered soundscapes by sending each audio input to different filter routings, such as VCF, BPF, or both. Additionally, the CV modulations offer a wide range of possible sound variations, which can be combined with external signals such as a keyboard voltage to create unique and expressive sounds. To achieve the best audio quality and avoid audible thump, it is recommended to combine the SH5-VCF with a post-filter VCA, such as the G-Storm Electro 2xVCA.