Reference · Tiles
TILEEVERY ENCLOSUREDBSPL (dB)
How loud each design plays at each frequency, at its set power and EQ and your listening distance. It is the tile to judge bass extension and response shape on, and to shape with EQ.
- Shows
- Sound pressure level in dB at each frequency for every visible enclosure, at its power and EQ, the radiation space and the listening distance.
- Healthy when
- The curve is smooth through the band you want, and F3 sits where you need the bass to reach.
- If it is not
- Change the box or tuning for extension and EQ for shape, then check the limits at the power you will use.
The tile#
SPL (dB)
dB
- Vented example, 1 Wloudest octave 88.1 dB
The vented example plays 88.1 dB averaged over its loudest octave at 1 W. The level is 3 dB below that at 30.3 Hz (F3) and 10 dB below at 24.9 Hz (F10).
- Open this example in the simulator and switch on F3 in the tile header for the markers. Hover the curve for the level at a frequency, or click the chart to hold the readout there.
- Each visible enclosure draws its own curve and its own markers, in its colour.
- A multiple-entry horn also draws a dashed line for each amplifier channel beside its solid total. The channels add with their phase, so the total is not the sum of their levels.
- The level is at the Radiation space and Listening distance set in the Environment section of the Driver panel: half space and 1 m unless you change them.
How to read it#
- Read the shape first: where the bass starts to fall, how steeply, and whether there is a hump or a dip on the way. Then read the level.
- F3 and F10 are measured down from each curve’s own loudest octave, not from a fixed level, so a quiet design and a loud one get comparable markers.
- The level follows the power: each doubling adds 3.0 dB. Compare designs at the same power, or on Transfer Function Magnitude, which takes the level out.
- This tile does not say whether the driver survives that level. Excursion, Max SPL (dB) and Headroom do.
- It is the response without a room. Radiation space adds the gain of nearby walls and floor, but room modes and reflections are not in it.
F-points#
F3 in the tile header shows or hides the markers. The cog beside it, F-point settings, chooses which ones and what they are measured from. On a desktop, Pin to side keeps those settings beside the chart.
| Setting | What it does | To start |
|---|---|---|
| F3, F6, F10 | Mark where each curve falls 3, 6 or 10 dB below its reference level. | F3 and F10 on, F6 off |
| Custom | A level of your own, from 0.1 to 80 dB down. | Off, at 4.7 dB |
| Baffle step Fc | Shows or hides the baffle step line, for enclosures that simulate it. | On |
| Active enclosure only | Markers for the selected enclosure only, instead of every visible one. | Off |
| Advanced › Reference level | What the markers are measured down from: Auto · loudest octave average, Selected band average over a band you type, or Response peak. It also lists each enclosure’s reference level and band. | Auto; a typed band starts at 50–100 Hz |
SPL (dB)
dB
- Bandpass example, 100 W
- Bandpass boxes and horns get two markers for each level, L at the low edge and H at the high edge. The bandpass example is 3 dB down at 38.9 Hz and 92.2 Hz, and 10 dB down at 27.2 Hz and 134 Hz.
- For a narrow bandpass box or a horn with separate humps, Auto can pick the wrong octave. Choose Selected band average and type the band you mean as the passband; humps outside it are ignored.
- A dip inside the band that falls below a marker’s level does not move the marker: markers show the outer edges, and Advanced notes the dip.
- The Metrics tile’s F3 and F10 always use Auto, whatever this tile is set to.
Other lines on the tile#
- PR marks a vented box’s port resonance: the frequency where the air in the port rings like an organ pipe. In the vented example it is at 482 Hz, past the default 400 Hz axis; set Upper frequency in Settings › Display… to 1 kHz to see it.
- A sixth-order bandpass box marks Front PR and Rear PR, and a horn with a ported rear chamber marks Rear PR. Here PR means port resonance, not passive radiator.
- A box with Simulate baffle step switched on, in the Baffle step section of the Enclosure panel, gets a line labelled Baffle at its transition frequency.
SPL (dB)
dB
- Baffle step off
- Baffle step on, 300 × 450 mm−6.0 dB at 20 Hz
On the sealed example, Simulate baffle step with the default 300 × 450 mm baffle puts the transition at 364 Hz. Below it the bass wraps round the box instead of going forward: the curve is 3.0 dB lower at the transition and 6.0 dB lower at 20 Hz. The most it takes is Step depth, 6 dB to start. It is a smooth shelf; the ripple a real baffle edge adds is not modelled. The Baffle Layout tile moves the driver on the baffle.
EQ on the tile#
- Every curve includes its enclosure’s EQ and filters that are switched on, whether or not you are editing them.
- Click EQ in the tile header to draw the selected enclosure’s filters over the chart and drag them into place. Exit puts the tile back.
- Right-click the chart and choose Add filter to put a high-pass, low-pass, parametric EQ, shelf or Linkwitz transform at the frequency you clicked.
- The EQ Editor tile is always in this mode. EQ and filters covers each handle.
What moves it#
| Change | Effect | Why |
|---|---|---|
| Double the power | +3.0 dB | The whole curve moves with the drive level. |
| Half space to quarter space | +6 dB | One more boundary next to the box. The same at every frequency for a box; a horn’s shape changes too. The app notes the offsets hold best at low frequencies. |
| Double the listening distance | −6.0 dB | Level falls with distance, and the tile reads it at the distance you set. |
| Simulate baffle step on | Up to −6 dB below the transition | A box on a stand loses the bass a wall would have sent forward. |
| Tune the vented example to 28 Hz instead of 36 Hz | F3 32.6 Hz → 29.6 Hz | Lower tuning reaches deeper; the port gets longer. |
| A high-pass filter | Less level below its corner | Every filter that is switched on is in the curve. |
Settings and controls#
| Control | Where | What it does |
|---|---|---|
| F3 | Tile header | Shows or hides the F-point markers. Off on a new tile. |
| F-point settings | The cog beside F3 | Which markers show and what they are measured from (above). |
| EQ | Tile header | Edits the selected enclosure’s filters on the chart. Exit leaves. |
| Y-axis settings | Tile header | Auto fits the curves; Manual takes a Min and Max. Either way the axis stops at 50 dB. |
| Add filter, Add note | Right-click the chart | A filter, or a note, at the frequency you clicked. |
| Fix | Over the chart | A design whose whole response is below 50 dB is left off the chart with a warning in its place. When the cause is a port with no room left (0 L), Fix takes you to the port settings. |
What to try#
| Try | What it changes |
|---|---|
| Mark F3 and F10 | Switch on F3 in the tile header to mark where each curve falls 3 dB and 10 dB below its loudest octave. |
| Shape it with EQ | Click EQ in the tile header, or right-click the chart and choose Add filter. The curve includes every filter that is switched on. |
| Check it can play that loud | This tile is at the set power. Max SPL (dB) shows how loud each design can go before excursion or heat stops it. |
Ask your AI#
Ask your AI
Your assistant runs the same solver on your own designs through the 00 Simulator connector.
Using 00 Simulator, simulate my open workspace and tell me each enclosure’s F3, F10 and the level of its loudest octave. Then put the SPL (dB) tile on screen and mark each F3 with a line.
Connect your assistant so it can open your designs.