Are old fashion photomultipliers used in LHC experiments? Are any photomultipliers used in any of LHC detectors? Or are only semiconductor devices used?
If yes, then where?
 A: Yes, photomultipliers are in use in calorimeters which use Cerenkov light to detect the passage of particles. An example is in this preprint of the Castor detector at CMS in LHC.

Charged particles penetrating the CASTOR calorimeter will generate showers in the tungsten absorber plates.
  These particle showers are sampled by using the Cherenkov effect. Quartz plates are the active medium to generate
  the Cherenkov light. They are in the form of thin plates inclined by 45± with respect to the beam axis in order
  to maximize the Cherenkov light. Cherenkov light generated by the charged particles carries the particle-related
  information. In the CASTOR calorimeter the R5380Q PMT series of Hamamatsu will be used to read out the
  Cherenkov light (see Table 1 for CASTOR PMT specifications). The Cherenkov light produced in the quartz
  plates will be transmitted to the PMTs by the mediation of the air filled light guides.

If you go to the document search page of CERN and search for photomultipliers and CMS you will find many references, though most behind paywalls. This is how I got the preprint above.
