When browsing audio equipment catalogs or websites, you're confronted with a barrage of technical specifications that can seem like a foreign language if you're not an audio engineer. Yet these specifications contain crucial information that helps determine whether a particular piece of equipment is suitable for your needs.
This guide aims to demystify common audio specifications, explaining what they mean in practical terms and how they affect your real-world experience with the equipment.
Speaker Specifications
Let's start with speakers, which come with some of the most important specifications to understand:
Frequency Response
Frequency response describes the range of frequencies a speaker can reproduce and how evenly it reproduces them. It's typically expressed as a range (e.g., "45Hz-20kHz") and sometimes includes a tolerance figure (e.g., "45Hz-20kHz ±3dB").
What It Means in Practice:
- Lower number: How deep the bass response goes (lower is better for full-range sound)
- Higher number: Maximum treble frequency (20kHz is standard, as it's the theoretical upper limit of human hearing)
- Tolerance (±dB): How evenly the speaker reproduces frequencies across its range (smaller number means more consistent reproduction)
For speech reinforcement, a frequency range of around 100Hz-12kHz is often sufficient. For music reproduction, particularly genres with significant bass content, look for systems that extend down to at least 40-50Hz (or pair speakers with subwoofers that handle the lowest frequencies).
Sensitivity
Sensitivity indicates how efficiently a speaker converts power into sound. It's measured in decibels (dB) produced at a distance of 1 meter when powered with 1 watt of input.
What It Means in Practice:
Higher sensitivity means the speaker produces more volume with less power. For example:
- A speaker with 90dB sensitivity will produce 90dB at 1 meter when powered with 1 watt
- A speaker with 96dB sensitivity will produce 96dB at 1 meter with the same 1 watt
This 6dB difference is significant – the higher sensitivity speaker would require only 1/4 the power to achieve the same volume level.
Higher sensitivity speakers are particularly valuable for battery-powered systems or situations where power is limited. However, they may sacrifice other qualities to achieve this efficiency.
Power Handling
Power handling indicates how much electrical power a speaker can safely handle. It's typically expressed in watts and may include several different ratings:
- Continuous/RMS Power: The amount of power the speaker can handle continuously (most conservative and reliable specification)
- Program/Music Power: Typically twice the continuous rating, accounting for the dynamic nature of music
- Peak Power: The maximum power the speaker can handle for very brief periods (often a marketing figure with limited practical value)
What It Means in Practice:
Higher power handling does NOT necessarily mean louder speakers – sensitivity is more important for efficiency. Power handling indicates durability and headroom.
Always use the continuous/RMS rating when comparing speakers or matching them with amplifiers.
Maximum SPL
Maximum Sound Pressure Level (Max SPL) indicates the loudest sound level a speaker can produce before distortion becomes unacceptable. It's measured in decibels (dB).
What It Means in Practice:
This specification combines sensitivity and power handling to tell you how loud a speaker can get. For reference:
- 90-100 dB: Suitable for speech in quiet environments
- 100-110 dB: Adequate for background music or small gatherings
- 110-120 dB: Appropriate for live music or larger events
- 120+ dB: Necessary for concerts and large venues
Remember that SPL decreases with distance – typically by 6dB each time you double the distance from the speaker. This means a speaker producing 100dB at 1 meter will produce approximately 94dB at 2 meters, 88dB at 4 meters, and so on.
Coverage Pattern/Dispersion
This specification indicates the angle at which sound spreads out from the speaker, typically expressed as two numbers representing horizontal and vertical coverage (e.g., "90° H × 60° V").
What It Means in Practice:
Coverage pattern helps you determine:
- How many speakers you need to cover your audience area
- How to position speakers for optimal coverage
- Whether a speaker is designed for wide coverage or more focused sound projection
Wide dispersion (e.g., 90° or more) is ideal for situations where the audience is spread out. Narrow dispersion can be beneficial for focusing sound in specific areas or minimizing reflections in challenging acoustic environments.
Amplifier Specifications
For systems with separate amplifiers and speakers, understanding amplifier specifications is crucial:
Power Output
Power output indicates how much power an amplifier can deliver to speakers. It's measured in watts and should be specified along with:
- The impedance at which it was measured (typically 4, 8, or 16 ohms)
- Whether it's continuous/RMS, program, or peak power
- The conditions under which it was measured (e.g., frequency range, distortion level)
What It Means in Practice:
When matching amplifiers to speakers:
- The amplifier's continuous/RMS power output should be roughly equal to or slightly greater than the speaker's continuous/RMS power handling
- Underpowered amplifiers can be more dangerous to speakers than overpowered ones (as they're more likely to clip/distort)
- Power output at the speaker's specific impedance is what matters (e.g., if you have 8-ohm speakers, look at the amplifier's output at 8 ohms)
Damping Factor
Damping factor indicates an amplifier's ability to control speaker movement, particularly in low-frequency reproduction. It's a ratio calculated by dividing the speaker impedance by the amplifier's output impedance.
What It Means in Practice:
Higher damping factors (typically >200) generally provide:
- Tighter bass response
- Better control of speaker movement
- Reduced distortion, particularly at lower frequencies
Damping factor becomes less significant with longer speaker cables, so keep cable runs as short as practical for optimal performance.
Signal-to-Noise Ratio (SNR)
Signal-to-Noise Ratio indicates how much louder the intended audio signal is compared to the amplifier's background noise. It's measured in decibels (dB).
What It Means in Practice:
- Higher numbers are better (e.g., 100dB is better than 90dB)
- For professional applications, look for SNR of at least 95dB
- This specification is particularly important for quieter environments or applications requiring high fidelity
Mixer Specifications
Mixing consoles come with their own set of important specifications:
Channel Count
Channel count indicates how many separate audio sources the mixer can accommodate. This may be broken down into various input types:
- Microphone inputs (XLR)
- Line inputs (TRS/TS)
- Stereo inputs
- Digital inputs
What It Means in Practice:
When selecting a mixer, consider:
- The total number of sources you need to mix simultaneously
- The specific types of inputs required
- Future expansion needs (add 20-30% more channels than currently required)
Buses and Auxiliary Sends
Buses are internal signal paths that allow you to route multiple channels to a single output. Auxiliary sends enable you to create separate mixes for monitors, effects, or recording.
What It Means in Practice:
- Main Mix Bus: The primary output that goes to your audience
- Group Buses: Allow you to control multiple related channels together (e.g., all drums)
- Auxiliary Sends: Create independent mixes for stage monitors, effects processors, or recording feeds
More complex events require more buses and auxiliary sends. For simple presentations, 1-2 auxiliary sends may be sufficient. For band performances with multiple monitor mixes, 4-6 auxiliaries are often needed.
EQ and Processing
This specification describes the equalizers and other processors included on each channel or bus.
Common EQ Configurations:
- 2-Band EQ: Basic high/low adjustment (limited flexibility)
- 3-Band EQ: High, mid, low adjustment (adequate for simple applications)
- 4-Band EQ: High, high-mid, low-mid, low adjustment (good flexibility)
- Parametric EQ: Allows adjustment of frequency, bandwidth, and level (most flexible)
Digital mixers often include additional processing like compression, gates, effects, and automatic feedback suppression. These features can eliminate the need for external processors, saving space and simplifying setup.
Microphone Specifications
Microphones have several key specifications that affect their performance:
Polar Pattern
The polar pattern describes a microphone's sensitivity to sound from different directions:
- Cardioid: Heart-shaped pattern that captures sound primarily from the front
- Supercardioid/Hypercardioid: Tighter patterns with some rear sensitivity
- Omnidirectional: Captures sound equally from all directions
- Figure-8/Bidirectional: Captures from front and back, rejects sides
What It Means in Practice:
- Cardioid: Best for isolating a single source, reducing background noise or feedback (ideal for most live applications)
- Supercardioid: Better isolation but requires careful monitor placement (good for noisy environments)
- Omnidirectional: Natural sound but susceptible to feedback (good for recording or capturing room ambience)
- Figure-8: Useful for interviewing or capturing two sources face-to-face
Frequency Response
Like speakers, microphones have a frequency response specification indicating the range of frequencies they can capture and how evenly they capture them.
What It Means in Practice:
- Flatter responses (without peaks or dips) generally provide more natural sound reproduction
- Some microphones are deliberately designed with frequency response characteristics that complement specific applications (e.g., vocal mics often have a presence boost around 3-5kHz)
- The shape of the frequency response curve is often more important than the absolute range
Sensitivity
Microphone sensitivity indicates how effectively the microphone converts acoustic pressure into electrical signal. It's typically measured in millivolts per pascal (mV/Pa) or decibels relative to 1 volt per pascal (dBV/Pa).
What It Means in Practice:
- Higher sensitivity (larger mV/Pa number or less negative dBV number) means the microphone produces a stronger output signal for a given sound pressure
- Higher sensitivity microphones require less preamplifier gain but may be more prone to overloading
- Lower sensitivity microphones may be better for very loud sources
Digital Audio Specifications
For digital audio equipment, these specifications are important to understand:
Sample Rate
Sample rate indicates how many times per second the audio is measured (sampled) in the digital conversion process. It's measured in Hertz (Hz) or kilohertz (kHz).
What It Means in Practice:
- 44.1kHz: CD-quality audio (adequate for most applications)
- 48kHz: Standard for professional audio and video production
- 96kHz/192kHz: Higher sample rates used in high-resolution audio production
Higher sample rates can capture higher frequencies, but the differences are often inaudible in live sound applications. For most events, 48kHz is the optimal balance of quality and processing efficiency.
Bit Depth
Bit depth determines the number of possible amplitude values in digital audio, affecting dynamic range and noise floor. Common values are 16, 24, and 32 bits.
What It Means in Practice:
- 16-bit: CD-quality audio with approximately 96dB dynamic range
- 24-bit: Professional standard with approximately 144dB theoretical dynamic range
- 32-bit float: Offers virtually unlimited headroom for internal processing
For live sound, 24-bit is the standard for optimal quality. The theoretical dynamic range exceeds what's practically usable in most live environments.
Latency
Latency refers to the delay introduced when audio passes through digital systems. It's measured in milliseconds (ms) or samples.
What It Means in Practice:
- Below 10ms: Generally imperceptible
- 10-20ms: May be noticeable in monitoring situations
- Above 20ms: Can cause monitoring problems and coordination issues for performers
Lower latency is particularly important for in-ear monitoring and live digital processing. Some digital equipment offers low-latency monitoring paths specifically for performers.
Making Sense of Specifications in Real-World Applications
Now that we've covered individual specifications, here's how to apply this knowledge when selecting equipment for specific applications:
Speech Reinforcement (Corporate Events, Presentations)
Priority specifications:
- Speakers: Clear midrange response (for vocal intelligibility), moderate SPL capability, wide and even coverage
- Microphones: Cardioid pattern, speech-optimized frequency response, good off-axis rejection
- Mixers: Clean preamps, feedback suppression capabilities, simple operation
Live Music (Bands, Concerts)
Priority specifications:
- Speakers: Full frequency range, high maximum SPL, controlled dispersion
- Amplifiers: Sufficient headroom, low distortion, good damping factor
- Mixers: Multiple auxiliary sends for monitors, comprehensive EQ, adequate input count
- Microphones: Application-specific models with appropriate polar patterns and frequency response characteristics
DJ Performance
Priority specifications:
- Speakers: Extended low-frequency response, high maximum SPL, good transient response
- Subwoofers: Low frequency extension, high power handling, controlled dispersion
- Amplifiers: Substantial power output, thermal stability for continuous operation
- Mixers: Low noise, good headphone monitoring options, flexible routing
Conclusion: Beyond the Numbers
While understanding specifications is valuable, remember that numbers alone don't tell the complete story. Factors like build quality, reliability, ease of use, and subjective sound character also play crucial roles in equipment selection.
The best approach is to use specifications as a starting point to identify equipment that's potentially suitable for your needs, then make final decisions based on:
- Listening tests whenever possible
- Reviews and recommendations from trusted sources
- Consultation with audio professionals familiar with your specific requirements
At PiratSwapr, our team of audio specialists can help you navigate these technical specifications and select the ideal equipment for your specific event needs. We believe in matching the right tools to the job rather than simply providing the most expensive or feature-laden options.
Whether you're planning a corporate presentation, wedding reception, concert, or festival across the Czech Republic, contact us for expert guidance on creating the perfect sound system for your event.
