One of the hardest questions to answer is which brand should you choose.
There are hundreds of brands on the market, each catering for a specific need and price bracket. Unfortunately there are not a great many resources providing feedback regarding tried and tested equipment. Every equipment producer will always promote their product with a bias towards making a sale (which is only natural), however your aim is to purchase equipment which fits your requirements exactly. I would recommend watching acts at different sized venues and listening to the quality of sound. Choose acts which have the same number of band members as your own, to ensure the equipment setup is feasible for your own purpose. You may hear a great sound from a five piece band, however the likelihood is that there would be a lot of equipment used that would not be necessary for a smaller setup.
Don't be afraid to approach the artistes with a few questions, as many people are only too willing to provide honest feedback on equipment they are currently using, and equipment they have previously purchased, and now avoid. These are the best people to provide advice as they are not trying to sell the equipment, and have also had the opportunity to put the equipment through it's paces.
Once you watch a vocalist or band, try and focus on the sound, this is not necessarily the quality of the music, more importantly it is the depth and clarity of sound coming from the speakers. Try and listen to the bass notes (are they deep but still smooth), the high notes (are they clear, but not uncomfortable), and the vocals (do they add richness to the singer's voice, without being uncomfortable to the ear). If the answers to these questions are yes, the chances are that you are listening to good equipment, which has been set up correctly. Take a note of the brands of equipment used, and use this as a basis from which you can now look around with a view to purchasing.
You may not find that everything falls into place immediately, as the equipment may be too expensive, or difficult to locate, however the main thing is that you have now listened to equipment in it's natural setting, and have gained some knowledge about which equipment sounds good, and which to avoid. You will undoubtedly find that you start to see the same brands and models of speakers/amplifiers/microphones appearing on stage time and time again. This is always a good sign that the equipment is preferred by the majority.
Some typical well-established brands are:
Mackie, EV (Electro-Voice), RCF (purchased by Mackie in the mid-90's), Crown, Nexo, Dynacord, QSC, Crest, Roland, JBL, Boss, Alesis, Tascam (Teac Professional Division), Studiomaster, Peavey, Sennheiser, Shure, Lexicon, Soundtech, Beyerdynamic, Chevin, Cerwin-Vega, AKG, Audio-Technica, Soundcraft, Yamaha, Beyerdynamic, Bose, DAS, Allen & Heath and Marshall.
Although there are hundreds of brands to choose from, it is important to remember that although a product may carry a brand name, there are always low-budget pieces of equipment produced by these companies, which may not sound anywhere near as good as the mid to higher range of equipment. As the saying goes; 'Rome wasn't built in a day' therefore it is worth realising that you may not immediately purchase the setup of your preference, due to available budget or availability of product. In this case, the lower end branded product or higher-end non branded product may suffice.
Big Is Not Always Better
A common mistake made by many people is to purchase an incompatible system. This is the equivalent of throwing money down the drain. Regarding sound quality, your system can be split approximately into two halves (50% of quality comes from the speakers, the other 50% comes from the amplifier/mixer/microphone and effects). One doesn't perform to it's potential without the other. For example, due to available budget, purchase may be made of a set of expensive high output professional speakers, however only a small amplifier can be afforded.
The problem here is that although the speakers can handle 10 times the power that your amplifier can produce, they will never sound as good as intended, and probably only sound as good as a low-budget speaker. A speaker needs to be 'driven' to a certain volume before it displays the characteristics that makes it a good speaker. If the power is too low, or the speaker cannot be used at a high enough level (perhaps due to the size of venues that are being played), then it will not perform to it's potential. Similarly if you purchase a huge expensive amplifier but can only afford lower quality/output speakers, the same rule applies.
Speakers/amplifiers only running at a small portion of their intended capacity will only produce a small portion of their intended quality. The general rule of thumb is to decide on your budget, and then purchase compatible speakers and amplifiers. They do not need to be of the same brand (and in many cases are not), however the size of venues and handling capacity needs careful consideration.
A Word Of Caution
Please resist the temptation to try and gig with a TV/Video surround-sound system. There have been a few people who have purchased a large surround-sound system thinking that the sound quality in their home lounge will be replicated in a pub or club environment. There is always huge disappointment when it becomes clear that the sound has little chance of carrying past the first twenty feet or so. A dedicated PA amp/speaker set-up is the only cost-effective way to offer a professional experience to the public.
Product Worth A Mention
Although we appreciate that artists will always have a preference, every once in a while a product is produced which stands the test of time regarding performance and durability. One of the products we feel we must give a mention to is the Shure SM58 microphone. Still used by seasoned pro's today, if you want a durable first microphone and are on a limited budget, you can't go far wrong using one of these. Over a number of years the SM58 became the vocal industry standard for consistent performance and durability that very few other microphones have been able to emulate.
To avoid worry about compatibility and technicalities, the safest route as a beginner is to follow paragraph one, and listen to the various products in their natural surrounding. After all, you know what you like to hear - and if it sounds good to you when listening as a member of the audience, you won't go far wrong with a similar setup.