The ISA One microphone preamplifier delivers Focusrite's prestigious ISA transformer-based preamp in a rugged and portable chassis. ISA One features the classic vintage microphone preamplifier topology from the original ISA110 module, including the Lundahl L1538 transformer and bespoke zobel network. The preamp is complemented by a line input and an independent D.I. channel, complete with dedicated gain control, active or passive impedance switch, a TRS Jack output for routing to an amp and an independent XLR output on the rear panel. This flexible, independent D.I. makes the ISA One ideal both for engineers wishing to blend a D.I.’d guitar signal with a mic’d guitar cabinet, and for demanding performers who require a single classic solution for both guitar and vocals.