Studio monitors are a playback device in the signal chain. They are the final link in the chain that takes all of the digital data and makes it analog, so our ears can here hear it. Studio monitors must be revealing of every sound in the recording. Each sound from a vocal or instrument must be heard over and over again time after time. They are designed to be painfully honest. They achieve this honesty with a flat frequency response.
Flat Frequency Response
A flat frequency response will not add any coloration to the sound or signal. It is not their job to sound real musical. It is their job to reveal the actual signal as it exists in the recording. Contrast this approach with that of a hi-fi speaker. A playback hi-fi speaker will have a frequency response curve that represents what the designer intended for a certain sound quality. This sound designed into the speaker can take into consideration the room’s response. A studio monitor does not figure any room response into their sound. In fact, most are designed to be listened to in a near field environment which minimizes room sound.
Studio monitors are designed with the full knowledge that they are a tool. A tool that will be listened to over and over. They must be able to pass this time test period without causing listener fatigue. Clarity of signal is critical. It is the distortion that is created when the signal is amplified and poorly processed. It is distortion that causes listening fatigue, not the time spent listening. Higher sound pressure levels will produce higher levels of distortion. If the engineer’s ears are tired, he will make decisions for the mix that he would not have made if he wasn’t fatigued.
Power requirements differ for each speaker type and studio monitors are no exception. If we look at hi-fi speakers, we know that that they are similar to monitors in that they are detailed and accurate. However, in exchange for all this sonic detail, they can not be played at the high pressure levels “demanded” by today’s professional engineering community. A hi-fi speaker can be easily damaged with too much gain from the amplifier. Sound reinforcement speakers must play loud. They must reinforce the existing sound with more sound. Quality of the sound produced is important but their main design goals are to play loud over extended time periods.
Active And Passive
Studio monitors come in two different classes depending on how they choose to process the energy the amplifier sends them. The technical terms used are directed at the crossover which is the gate keeper for sound energy from the amplifier. With studio monitors we can have active and passive crossovers. All multiple driver speakers have a crossover to decide how the sound from the amplifier will be distributed. With a passive crossover, it is usually positioned inside the speaker and the speaker designer presets the crossover frequencies to achieve the sound he wants for the speaker design.
In an active crossover, the speakers also become active speakers. Active speakers have a line level input similar to a power amplifier. Our source signal is sent to the crossover and then to the power amplifier before going to the speakers. When our source signal hits the active crossover, high frequencies can be directed to one power amplifier to cover the middle and high frequencies. The low frequencies can then be sent to another amplifier. This ability to process if you will our signal in this manner allows us to match the amplifiers to the speakers.
Studio monitors are a type of hybrid speaker with features and benefits borrowed from both hi-fi and sound reinforcement speakers. Accuracy and detail is incredibly important because we want everything in the recording revealed to the engineer’s ears. Hi-fi speakers do a good job with this. High sound pressure output over extended periods of time is also a requirement. Clients want to hear how their music sounds with regular, medium, and high volumes. In some current musical genres, it is mostly how does it sound loud. Loud is not viewed as a negative.
It also allows for better transient coverage. When a bass note is played at the same time a guitar note is played, the amplifier will have to send more energy to reproduce the bass note. The guitar note will be short changed because the bass note took more energy from the amplifier. With the ability to have bass notes reproduced with their own amplifier behind them and the mids and highs having their own amplifier, there will be plenty of energy for the mids and highs to be heard.
Studio monitors are a blend of other speaker types. They take the detail and accuracy from their hi-fi brothers and their ability to play loud from their sound reinforcement cousins. Studio monitors speak only one language and that is honesty and faith to the recording. They achieve this sonic goal showing a flat frequency response. They are designed to reveal and revel in the music at any pressure level, especially loud. They like to be heard over and over again.