Roger Waters

During most of the 70s Roger's rig consisted of Hiwatt Custom 100 DR103s and WEM Super Starfinder 200 (4x12) cabinets. This setup would last utnil about 1978 when Phil Taylor built him a new Phase Linear 700 amplified bass rig.

"Waters uses an Ampeg SVT-6 Pro, with one spare, through three 4x10 cabs rewired to 8 ohms (two running with one spare). The same system is used throughout the Dark Side of the Moon and The Wall tours," according to this Premier Guitar Rig Rundown.

"We have three 4x10s which Ampeg has rewired the cabinets for use, to run 8 ohms instead of 4 ohms," says Waters' guitar tech, at 4:20 in this rig rundown video.

"Back in the 70s I used a Strat with a Fender Twin..."

It is stated in the linked article that Waters was seen in the studio and on stage with his IC100 throughout the 1970s. The article also gives the example of studio use together with a Binson Echorec delay unit to produce the tremolo effect on One of These Days track, 2:00 - 2:30.

You can see Roger's stack behind Gilmour's arm, intercut throughout "the funk section" of Echoes on Pompeii, starting at 6:53. https://youtu.be/b6uA02ggGD0?t=413

Roger Waters, alongside David Gilmour, utilized the WEM Super Starfinder 200 Cabinets extensively throughout their career with Pink Floyd, as detailed on Watersish.com.

Roger played through the Hiwatt Custom 200 bas amp DR201, during the 2017 - 2018 Us + Them World Tour.

Roger played through the Hiwatt Full Range SE41115 Bass Cabinet, during the 2017 - 2018 Us + Them World Tour.

Roger's rig for the Wall recording sessions at Britannia Row (1979) included Fender Bassman 50 amp with a matching 2x15" speaker cabinet (while for the Los Angeles sessions he used an early '60s Ampeg B18N blue Portaflex with 18" bass driver). [...] The Bassman 50 model with silverface piggyback head that Roger Waters had during the Wall sessions in London, was manufactured by Fender between 1972 - 1977. It featured 50-watt RMS power with 110-watt peak music power, dual channels with separate control on each, "deep" switch in bass channel and "bright" switch in normal channel.