Documented extensively by Kit Rae in part 2 of his "David Gilmour Tone Building" subpage "Amplifiers and Speakers".

David's WEM speaker cabinets are typically loaded with Fane Crescendo 100w 12" speakers. They are a perfect speaker to blend with the Hiwatt sound, and out of all of David's gear, the Hiwatt/Crescendo combo could be said to define the core foundational tone heard in most Gilmour performances. The Crescendos have a distinct bright tone that accents the upper mid range. The sound is very detailed and cuts straight through in a band mix. The bright mid range is almost too bright with certain amps, like Marshalls, but works well with a Hiwatt and most Fender amps. It is perfect with mid-scooped pedals like the Big Muff and B.K. Butler Tube Driver.

"One of the first jobs I did in the band was to go out and buy him (Gilmour) some new Hiwatt amplifiers. I went down to Hi-Watt in Kingston (in 1974) and saw Dave Reeves and bought two 100 watt heads which are still in Dave's rack today. He had WEM 4x12 cabinets with Fane Crescendo speakers in, identical to the ones he uses now…" - Phil Taylor, Guitarist Magazine Jan 1995

"I have two new 100-watt Fender Twin Reverb heads running to two 4xl2 cabinets each-two WEM cabinets with Fane Crescendo speakers and two Marshall cabinets with Celestions." - David Gilmour, Guitar Player, Nov 1984

Fane Crescendo speakers were made by the legendary British loudspeaker company Fane throughout in the 1960s, '70s, and '80s. In the 1970s Fane made speakers for Selmer, Watkins (WEM), Simms-Watts, and Dave Reeves of Sound City and Hiwatt fame, which is likely where Pink Floyd was first introduced to them. Fane produced a massive number of speaker models with many different options, so there is not one "Fane" sound, and the Crescendos sounded very different to other Fanes. There were also several different Fane Crescendo models with various speaker frame designs and labels. The original Crescendos were 12" 100w, 15" 100w, and 18" 150w models, all available in both 8 ohm and 15-16ohm. Two common types of 12" Crescendos were made in the 1970s - type 'A' general purpose speakers, with aluminum dust caps, and type 'B' or 'B/L' for bass and organs, with plastic treated linen dust caps.

The type of 12" Crescendos David Gilmour has used since the early 1970s are type 'A', with the identification code 122326 ink stamped on the speaker frame. These had large ceramic (anisotrophic ferrite) magnets, 20,000 gauss flux density, 2" voice coils with fiberglass formers, and 3" diameter aluminum dust caps with a round, felt diffuser mounted in the center. Aluminum caps were popular with many speaker manufactureres in the 1970s. They accented more of the upper mid range than paper or cloth dust caps, adding a unique, jangly top end to the Crescendo sound. They brought out much more detail in the top end than paper or cloth, but some found the sound too harsh. They work very well with the Hiwatt frequency range however. These silver dust caps can be seen through the grille cloth in David's 1994, 2006, and 2015/16 tour speaker cabinets. It is not clear if David has always used type A Crescendos with silver dust caps, but they can be seen in several of his WEM cab photos from 1973 and 1974, so he has probably always favored this speaker. Little is known about the speakers in David's combo amplifiers, but Phil Taylor revealed in a 2015 interview (Feb 2015 Guitarist Magzine) that David also uses Fane Crescendos in his Hiwatt SA212 combo studio amp.

That Hiwatt SA212 (and, therefore, the Fane Crescendo) was also used on The Endless River, as mentioned by Phil Taylor in this February 10, 2015 Music Radar interview about the contents of Astoria and Medina.

Left to right: 1958 FENDER Tweed Twin, 1976 Yamaha RA200 Rotary speaker with Alembic preamp, 1970s Hiwatt SA212, Alessandro Redbone Special, Leslie Model G27 cab

“These were David’s main amps on The Endless River,” comments phil Taylor on the beautiful array of vintage and modern amps in the studio’s live room. “He also used the Leslie Studio 12 cab with the Allesandro Redbone Special 55-watt model.”

(...) The Hiwatt SA212 combo is a staple of Gilmour’s recording rig. powered by a brace of el34s, it is fitted with Fane crescendo drivers.