How Loud Can a Speaker Go? Max SPL and Cone Excursion
A speaker's bass SPL ceiling is cone area times excursion: the closed form, required excursion by size, and why an octave down costs four times more.
Why Do My Left and Right Speakers Measure Differently?
Left and right speakers rarely measure the same, and the cause is usually placement, not unit variation. Measure one side at a time, then swap them to prove it.
Speaker or Room? Separate Them With Two Measurements
Is that dip your speaker or your room? Measure the same speaker at two distances, overlay the curves, and read where they diverge. Boundary: 250-300 Hz.
Speaker Measurement Apps Compared: What Each One Measures
Which apps measure a speaker's frequency response? REW, SignalScope, AudioTools and Sonir compared on impulse response, channel gaps and repeatability.
How to Measure Speaker Frequency Response with a Phone
Measure a speaker's frequency response with your phone, and read the result correctly. Why the curve is always speaker plus room, how to weight it toward the gear, and how to measure left and right separately.
Five Steps to Check If a Hi-Res File Is Real
How to check whether a hi-res file is genuine from its spectrum: let the declared sample rate pick the yardstick, then read effective bandwidth, roll-off, and the confidence value, with the cases where the verdict misses.
Why an A/B comparison is worthless without level matching
Half a decibel is enough to make the louder side sound better. Here's why loudness matching decides the verdict, and how to match with LUFS rather than peak values.
What are standing waves? Why your room's bass misbehaves
Standing waves are room resonances set by wall-to-wall distance: 172 ÷ L in metres. They put ±10 dB peaks and dips in the low end, and the dips can't be filled with EQ.
How do you export PEQ to REW or Equalizer APO?
Sonir's auto PEQ leaves as one REW Filter Settings text file. REW reads it directly, and the Preamp and Filter lines drop into Equalizer APO's config.txt.
How to Read a Waterfall Plot: Finding the Band That Rings
A waterfall (CSD) plot maps frequency, time and level. How to read it, why a single slow band means ringing, and where the resolution runs out in the bass.
Where Should You Put the Mic for Room Measurements?
Mic placement for acoustic measurement starts at the seat you actually listen from, at ear height. Put it on a tripod, keep it off walls and desks, and use 2-3 m for the room, ~1 m for the gear.
EDT, C50 and C80: How They Differ from RT60
EDT reads the first 10 dB of the decay, C50 and C80 compare early energy against late. Here's what each metric measures, how they differ from RT60, and when to read which.
Measurement Apps With Calibration File Support Compared
Which measurement apps read a calibration mic's .txt file? SignalScope, AudioTools, REW and Sonir compared on how far the correction reaches.
How much of the room ends up in an air recording?
How much room lands in an air recording comes down to mic distance and band. Past the critical distance the room wins, plus how to still tell gear apart.
Built-in vs USB mic: how much does it change?
A built-in mic and a USB mic differ in four places for air recording: band edges, noise floor, automatic gain and imaging. Plus what calibration unlocks.
Do you need more than a smartphone for air recording?
Air recording starts with a smartphone and nothing else. Here is what the built-in mic covers, and the order to add a tripod, a USB mic and calibration.
How to Spot Fake Hi-Res Audio in the Spectrum
How to spot fake hi-res audio. Read the upper band limit and the shape of the roll-off to tell a genuine high-resolution file from a CD or lossy source that was upconverted.
Why Does the Same Speaker Sound Different Every Take?
Recordings of the same speaker drift because of four things: the source, the level, distance and mic position, and the room, and how to pin all four down.
How to Compare Speakers A/B Fairly: 3 Things to Match
A fair speaker A/B comes down to three things kept identical: mic position, stimulus, and playback level. Then read the difference curve A−B, not your ears.
Can You Trust Frequency Response Without a Calibration Mic?
Frequency response without a calibration mic: big low-frequency room peaks and same-mic A/B hold up; absolute SPL and treble detail need a calibration file.
Which frequencies should you fix first with room EQ?
Room EQ belongs in 20–300 Hz, where room modes dominate. Above that, response is position-dependent and point corrections make it worse. Cut peaks.
What dBFS should you record at for measurement?
Set your measurement recording peak to -6 to -12 dBFS: high enough to clear the noise floor, low enough to leave headroom before clipping breaks the IR. Gain SNR from sweep length, not volume.
Sweep vs clap: which IR measurement is more accurate?
Sweep vs clap for impulse response (IR) measurement: why a log sweep wins on SNR, low-end coverage and distortion rejection, and when a hand clap is still good enough for RT60.
Why Is RT60 Too Long? Usually the Recording, Not the Room
An RT60 reading too long is usually the recording clipping, not the room. How a crushed decay curve flattens the slope, and the fix that keeps the peak at -6 to -12 dBFS.
How Much RT60 Is Good for a Listening Room?
A good RT60 for a listening room is roughly 0.3–0.5 s mid-band. Targets by use, plus the symptoms of a room that's too live or too dead.
Decibel X Alternatives: One-Time Purchase Options
A Decibel X alternative without a subscription? Compare it with AudioTools, REW and Sonir by pricing model, measurement depth and recording comparison.
Measuring Frequency Response and Room EQ on a Phone
Measure frequency response on a smartphone and apply room EQ: read the measured FR, auto-generate PEQ from the target difference, and export to REW / APO.
How Do You Measure RT60 With a Smartphone? 5 Steps
Measure RT60 with a smartphone in 5 steps: set the input peak to -6 to -12 dBFS, earn SNR from sweep length, build the IR, and read the decay curve so values hold up.
REW Alternative on Mobile: What a Phone Can Measure
A REW alternative on your phone: how desktop REW compares with mobile measurement (Sonir) on RT60, frequency response, room EQ, and distortion, and where a phone falls short.
Best RT60 measurement apps: which one to choose
Most phone audio apps are SPL meters; few actually compute RT60. We compare Decibel X, AudioTools, SignalScope, REW and Sonir by features and use case.
Record and Compare Your Gear Under the Same Conditions
Record and compare your audio gear under identical conditions. Fix level, distance, room, and mic, then read the recording score and overlay measurements on your phone.
Measuring Room Acoustics with a Smartphone: A Full Guide
Measuring room acoustics with a smartphone: how far a built-in mic gets you, from SPL and RTA to sweep-to-IR for RT60, frequency response and waterfall.
How to Measure RT60 with a Smartphone: A Full Guide
RT60 (reverberation time) on a smartphone: the definition, sweep-to-IR Schroeder integration, and the recording level and SNR that keep values reliable.