speakers (1970s) rotary sound amplifiers which produce Leslie speaker effects by rotating a series of speaker units instead of horns. also featuring Yamaha Natural Sound Speaker units CSY-2 (1975) R-60 (a combination of dual 3way normal speakers and dual 2way rotary speakers) RA-50 (1970s, single rotary + woofer) RA-70R RA-100 (1970s, dual rotary + woofer) RA-200R (1970s, triple rotary + woofer) — David Gilmour (Pink Floyd) used it along with Hiwatt amp between 1976 and 1983. TA series (late 1960s) wedge-shaped flat amplifiers, featuring Yamaha Natural Sound Speaker units TA-20 TA-30 (c. 1968, 30 W RMS/ 50 W music power) TA-60 (c. 1968, 60 W RMS/100 W music power) TA-90 (PE100 head + TS90 cabinet, 90 W RMS) VR series (1989–1991) VR-3000 (50 W @ 8Ω, 1x12" speaker, dual channel, 1 parametric EQ per channel, reverb) VR-4000 (stereo 2×25 W @ 8Ω, 2x10" speakers, dual channel, 1 parametric EQ per channel, reverb, chorus) VR-5000 (100 W @ 8Ω, 1x12" speaker, dual channel, 2 parametric EQ per channel, reverb) VR-6000 (stereo 2×50 W @ 8Ω, 2x12" speakers, dual channel, 2 parametric EQ per channel, reverb, chorus) VR-75B (75 W 15-inch bass amp) VR-150B (150 W 15-inch bass amp) VX series (red logo) VX10 (10 W combo) VX15 (10 W combo) VX25 (20 W combo) VX35 (30 W combo) VX25B (30 W combo bass amp) VX35B (30 W combo bass amp) VX55B (50 W combo bass amp) YTA series (1970s, blue line) YTA-15A YTA-95 (100 W 2×12-inch) YTA-110A B series bass amps Series I Series II 1982 Series III 1985 B50-115 (50 W bass combo) B100 (100 W head, successor to the J-100B) B100-115 I/II/III (100 W bass combo, 15-inch) B100-115SE (100 W bass combo, 15-inch smaller and lighter than the numbered series, 790mm tall and 44kg, vs 950mm and 52kg) S115 (15-inch bass cabinet to match B100 head) S215 (2×15-inch bass cabinet to match B100 head) BBT series digital bass amps BBT500H (head, 500 W@2Ω) BBT210S (cabinet, 2×10-inch) BBT410S (cabinet, 4×10-inch) BBT500-115 (combo, 500 W 15-inch) YBA series (1970s, blue line) YBA-45 Power amplifiers P/PC series power amplifiers P2500S P7000S PC-1002 Keyboard amplifiers MS101 / MS101-3 (powered monitor, 10 W 4-inch) SKS50 Percussion instruments Timpani All of the Timpani Models (except 9000) are balanced action. TP-3100 (Portable Aluminum Series) TP-4200 (Concert Series. Fiberglass) TP-6200 (Symphonic Series: Smooth Copper) TP-7200 (Hammered Symphonic. 4 mm Suspension Ring for Accurate Tuning) TP-9000 (Grand Concert