Description

Introduction: A generation of legendary classics - Marantz 7 (M7) vacuum tube preamp, sound quality is known for its mellow, medium frequency sweet and natural, vacuum tube rich taste! The circuit of this work is derived from the classic M7 circuit, and the necessary modifications and adjustments are made according to the characteristics of modern components (mainly coupling capacitors) and old antique capacitors. Vocal, natural, delicate, smooth strings, stretch, positioning and imagery. The high and low frequencies extend into place, and the low frequency dive is deep and powerful without lack of flexibility. Reasonable layout and connection, multi-level grounding, this product has no annoying noise, very quiet. High voltage: AC 200---220V, Not less 15mA Filament voltage: AC 12---14V, Not less 0.8A(This version uses DC filament power supply. (If the filament supply voltage is too high, the heat sink will be very hot.) Recommended use of the tube: 12AX7 and its compatible tube PCB Size：177mm * 152mm NOTE : ◆ PCB ---- Bare board PCB without any parts.