Q: How similar is live sound equipment to recording equipment?
There are a lot of similarities between the equipment that is used in recording and that used in live sound.
Starting with microphones, vocal mics tend to be either that good old favorite, the Shure SM58, or specialized live sound vocal mics. Many mics that work well in the studio are not practical for live use.
In the studio, all that is important is sound quality. In live sound, it is even more important that a mic should be resistant to feedback. It doesn't matter how good the vocal is if the speakers are howling. Live sound vocal mics tend to be handled more roughly, whereas in the studio you can handle a vocal mic with cotton gloves if you want. Toughness is a virtue for live sound.
For sound sources other than vocals, any microphones that are sufficiently robust can be used. It also helps if they are not too troubled by wind noise, for outdoor work.
Moving to microphone preamplifiers. Some live sound engineers insist on using their favorite preamps. However, 'exotic' preamps are used far less in live sound than they are in the studio. Live sound works to a much faster pace and it is important to have equipment that 'just works' rather than provides a subtle benefit that few in the crowd would probably hear. For most purposes, the preamps in the mixing console are absolutely fine.
Many studio recording engineers don't use a mixing console any more, preferring to connect their microphone preamplifiers directly to the audio interface of a digital audio workstation.
Although it is possible to use a suitably-specified DAW for live work, it is much more practical to use a purpose-designed mixing console. All the controls are easy to use and you don't have to stare at a screen looking for that tiny mouse pointer.
Although analog consoles are still used, digital consoles are popular because of their instant resettability. You can change over from one group of performers to another in a second, whereas with analog consoles it takes much longer.
Many types of hardware equipment are the same in recording and live sound. Compressors are the same, gates are the same, equalizers are the same. What suits one area of sound suits the other too. It's worth noting that graphic equalizers are more popular in live sound than in the studio.
In live sound, clearly the loudspeakers are very much bigger. There is a whole realm of knowledge and experience to be gained that you just wouldn't come across in the studio. Instead of one power amplifier, there's a whole rack. You will also find active crossover units and loudspeaker management units that are seldom seen in studios.
In summary, there are so many similarities between the equipment used in recording and live sound that an experienced recordist should be able to make the transfer quite quickly. There is a lot more hardware than software, but techniques learned using, for example, a DAW compressor, can easily be transferred to a compressor used in live sound, whether hardware or software.
Live sound techniques also have many similarities with recording, but that is a topic we will cover on another occasion.