- The One-Glance Exam Snapshot
- The CETa Prerequisite Rule
- All Eight Domains at a Glance
- Acoustics and Microphones: Core Facts
- Speakers, Sound and Measurements
- Wiring and 70-Volt Systems
- Troubleshooting, Safety, Codes and Standards
- Test-Day Mechanics
- After You Pass: Maintenance
- Sequencing Your Review by Domain
- FAQ
- The CAT exam is 100 questions in two hours, and you need 75% to pass.
- CAT is not stand-alone: Associate CETa certification must be acquired first.
- The $80 exam fee includes one free retake within one year of your first session.
- Eight competency categories are listed, but no percentage weighting is published for any of them.
The One-Glance Exam Snapshot
This page condenses what a Commercial Audio Technician (CAT) candidate needs to keep in front of them: the numbers, the structure and the technical topics that recur across the official competency list. CAT is administered by ETA International and is classified as a Journeyman-level credential covering the design, installation and troubleshooting of speech and music sound systems in commercial and institutional environments. Think conference rooms, houses of worship, school auditoriums, retail spaces and similar installed-sound venues.
| Item | CAT Fact |
|---|---|
| Governing body | ETA International |
| Classification | Journeyman |
| Exam fee | $80 USD |
| Questions | 100 |
| Time allowed | Two hours |
| Passing score | 75% |
| Hands-on assessment | Not required |
| Certification term | Four years |
| Retake | One free retake within one year of the first session |
| Prerequisite | Associate CETa certification first |
A 75% cut on 100 questions works out to 75 correct answers, which is a useful mental target when you take timed practice sets. For a deeper look at how that threshold plays out, see our breakdown of the CAT passing score.
The CETa Prerequisite Rule
The single most overlooked line on any CAT cheat sheet is the prerequisite. ETA's CAT-specific competency document states that this is not a stand-alone credential: Associate Certified Electronics Technician (CETa) certification must be acquired first. In practice, that means your plan needs two exams in sequence, not one.
If you have not yet earned CETa, start there. If you already hold it, your CAT preparation can focus entirely on audio-specific content.
All Eight Domains at a Glance
ETA's competency document organizes the exam into eight major categories. Important caveat: the published scope document lists the competencies but does not publish a percentage allocation per category. Do not assume any one domain is the heaviest, and do not assume they are weighted equally. Prepare for all eight. The document linked by ETA also carries a 2013 copyright, which is simply the date on the document and not evidence of a 2026 exam revision.
- Acoustics
- Microphones
- Speakers
- Sound & Measurements
- Wiring
- 70-Volt Systems
- Troubleshooting
- Safety, Codes and Standards
For a category-by-category walkthrough, our complete guide to all 8 CAT content areas expands on each one. The sections below give you the quick-reference version.
Acoustics and Microphones: Core Facts
Domain 1: Acoustics
Acoustics is the physics layer that every installed sound system sits on top of. Expect questions that connect room behavior to system design decisions.
- How sound travels, reflects, absorbs and diffuses in commercial rooms
- Reverberation and its effect on speech intelligibility
- Frequency, wavelength and how they relate to speaker and room interaction
- Why hard-surfaced venues (gyms, lobbies, sanctuaries) are harder to cover clearly than treated rooms
Domain 2: Microphones
Microphone questions tend to be applied: pick the right type and pattern for a scenario, and understand what goes wrong when you do not.
- Transducer types and their typical use cases in speech reinforcement
- Polar (pickup) patterns and where each one rejects sound
- Placement and its relationship to gain-before-feedback
- Balanced versus unbalanced connections and why installed systems favor balanced lines
Speakers, Sound and Measurements
Domain 3: Speakers
Speakers are where electrical power becomes acoustic coverage, so expect both electrical and placement questions.
- Loudspeaker components and how they split the frequency range
- Impedance and how it affects what an amplifier can safely drive
- Coverage patterns and aiming for even distribution
- Series versus parallel connection effects on total load
Domain 4: Sound & Measurements
This category rewards candidates who are comfortable with decibels and basic electrical measurements. Practice the math until it is automatic.
- Decibel concepts: what a change in dB means in practical terms
- Sound pressure level and how it falls off with distance
- Basic Ohm's law and power relationships used throughout audio work
- Using test and measurement tools appropriately
Because a nonprogrammable scientific calculator is permitted under ETA's general examination rules, drill the dB and Ohm's-law calculations on the same kind of calculator you will bring to the session.
Wiring and 70-Volt Systems
Domain 5: Wiring
Wiring questions reflect real installation practice: choosing cable, making clean connections and keeping signal paths quiet.
- Cable types and their appropriate applications
- Connector types and proper termination
- Grounding and shielding practices that limit hum and noise
- Signal-level distinctions (microphone, line and speaker level) and why they must not be mixed up
Domain 6: 70-Volt Systems
Constant-voltage distribution is a signature topic for commercial audio and a reliable source of exam questions. If your background is in consumer or live-sound audio, give this domain extra time.
- Why distributed-line systems exist: long cable runs and many speakers on one amplifier channel
- Transformer taps on speakers and how tap selection sets each speaker's power draw
- Totaling connected speaker wattage and keeping it within amplifier capacity
- Comparing constant-voltage and low-impedance (direct) distribution
Key Takeaway
For 70-volt problems, the core habit is simple: add up the tap wattages, compare the total to the amplifier's rating, and confirm every speaker is on the intended tap. Run several practice problems until you can do this without hesitation.
Troubleshooting, Safety, Codes and Standards
Domain 7: Troubleshooting
Troubleshooting questions are scenario-driven. They describe a symptom and ask for the most logical cause or next step.
- Following the signal path from source to speaker to isolate a fault
- Recognizing common symptoms: hum, buzz, distortion, no output, low output, feedback
- Separating source problems from wiring problems from amplifier or speaker problems
- Making one change at a time and verifying the result
Domain 8: Safety, Codes and Standards
Installed systems sit inside buildings, so electrical safety and code compliance are part of the job and part of the exam.
- Electrical safety practices when working around power and amplifiers
- Code considerations for wiring methods in commercial buildings
- Cable placement and routing concerns, including separation of power and signal
- Safe practices for equipment mounting and overhead speaker installation
Candidates often underestimate this last domain because it feels less technical than 70-volt math. Since no weighting is published, treat it as fully testable.
Test-Day Mechanics
ETA tests through a proctored process. Per ETA's administration details, testing is delivered through an ETA Certification Administrator using either Trapeza online testing or paper and pencil. The standard Trapeza route requires an onsite administrator, and ETA also offers a distinct remote-proctoring route through ExamRoom.AI.
- Photo identification is required.
- Scratch paper and a nonprogrammable scientific calculator are permitted under ETA's general rules; used scratch paper is surrendered afterward.
- Format: 100 questions in two hours, which averages to roughly 72 seconds per question. Flag the slow calculation questions and return to them after clearing the quick recall items.
- No hands-on component: the credential is earned through the written exam alone.
Scheduling depends on your administrator, so check availability early. Our guide to CAT exam dates and scheduling explains how to plan around that.
After You Pass: Maintenance
CAT carries a four-year certification term and follows ETA's general Maintenance track (not Maintenance with Hands-On). To keep the credential active, you submit the maintenance form and satisfy both of the following:
| Requirement | Annual | Over Four Years |
|---|---|---|
| Continuing education | 10 hours per year | 40 hours total |
| Maintenance fee | $25 per year | $100 total |
As an alternative to the continuing-education hours, ETA accepts qualifying supervisor-completed employer verification. The fee still applies. If you are weighing whether the ongoing commitment pays off, read our CAT ROI analysis, and for career context see the CAT salary guide.
Sequencing Your Review by Domain
If you only use one structured plan, tie it to the technical dependencies between domains. Foundational concepts first, applied problems last:
Acoustics and Microphones
- Lock in sound behavior, reverberation and pickup patterns
- Connect feedback causes across rooms and microphones
Speakers and Sound & Measurements
- Practice impedance, series/parallel and dB calculations daily
- Use your exam-approved calculator throughout
Wiring and 70-Volt Systems
- Work tap-wattage totals until they are routine
- Review cable, connector and grounding practices
Troubleshooting, Safety, Codes and Standards
- Walk signal paths through scenario questions
- Take full timed 100-question practice sets and review misses by domain
Troubleshooting comes last because it draws on everything before it. For a fuller plan, see the CAT study guide, and when you are ready to test yourself under timed conditions, try the CAT practice tests.
FAQ
The exam has 100 questions with a two-hour limit, and you need 75% to pass. That means answering 75 questions correctly. There is no hands-on portion.
Yes. ETA's CAT competency document states that CAT is not a stand-alone credential and that Associate Certified Electronics Technician (CETa) certification must be acquired first. See the CAT requirements guide for details.
ETA publishes the eight competency categories but no percentage allocation, so no domain can be called the largest. Study all eight: Acoustics, Microphones, Speakers, Sound & Measurements, Wiring, 70-Volt Systems, Troubleshooting, and Safety, Codes and Standards.
ETA offers one free retake within one year of your first examination session. Use your first attempt's weak areas to focus your retake preparation, and consider our CAT difficulty guide for expectations.
Maintenance requires the maintenance form, either 10 continuing-education hours per year (40 over four years) or qualifying supervisor-completed employer verification, plus $25 per year, totaling $100 across the four-year term.