It only gets better…
Available with the active XR Spectra configuration, the Tone Block is a small passive second-order (two-pole) resonant RLC filter with variable frequency and Q (resonance). It is specifically designed as a post filter for the XR Spectra pickups, giving you the freedom to change each pickup’s character on the fly.
With this update, the tone block is given its own buffer to isolate the input. What this means is that you can now connect one or more tone blocks in series or parallel, to allow multiple voicings. In addition, the new tone block version will also have a bypass switch. The bypass switch will give you quick access to two voicings per tone block.
You can have one tone block per XR Spectra pickup as originally suggested, or alternatively, for example, you can simply have two tone blocks placed before the volume control. Such an arrangement can actually be more versatile. Two tone blocks (in series or parallel) will give you four (4) voicings, multiplied by the number of switch settings (typically 2 or 5 way).
Oh and I should mention that the addition of a buffer makes the tone block general purpose. You can use them with any pickup, even piezo. For passive pickups, however, the downside is that you need to power it with a battery. But this can be a simple means to make a passive system active.