A set with an LED matrix. The brightness is adjustable, and you can also turn off the display. By eliminating any active electronics, a very clear and open sound is maintained. The design uses high quality Fujitsu FTR-B4CB4.5Z bistable relays, as well as mil-grade audio grade resistors RN55D, RLR07, CMF55 from Vishay-Dale, which have an excellent reputation in the audio field.
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