The Ares Vintage Preamp is a reproduction of the Echoplex EP-3 tape echo unit in bypass mode. The EP-3 was originally released in 1970 as a solid-state update to the previous tube-based versions. It became legendary not only for its tape delay effect, but also for the coloration that its preamp would add even with the echo turned off. It’s a pretty simple JFET gain stage, but it does something special with the phase response of the signal.
The Ares is more directly based on the ClinchFX EP-Pre, originally traced by Aion FX in 2015. It uses a charge pump to get 18 or 24v from a 9 or 12 volt source, which compares to the 20V supply of the original. There is also an output buffer added to the end so that it interacts more consistently with pedals that follow.
There were two versions of the EP-3: the early version which was brighter and the late version which was a little darker and fatter. The difference is a single capacitor that was added to the first JFET stage in the later version. The Ares has a toggle switch that allows you to switch between these two versions, as well as a third mode with another capacitor that thickens the tone even more.
Note that, like the original Echoplex preamp, there is very little overall gain available. With Volume at maximum, it only gets about 6dB above unity. Despite being called a preamp, this is not a boost pedal, but more of a tone enhancer or conditioner.