Cookbook

Cookbook · Sealed

15 L sealed subwoofer

Start with the Dayton Audio DCS205-4 in a 15 L sealed box. Compare its output at 40 Hz with the travel it needs, then try another driver in the same space.
Box
15 L sealed, net air volume
Starting drive
50 W, equivalent to 14.0 V RMS
Conditions
Half space at 1 m, 0.1 Ω series resistance

Keep the first experiment simple#

A sealed box removes port tuning and duct geometry from the experiment. The question becomes whether the driver and available air volume give useful extension and enough output before travel becomes the limit.

At the starting power, this driver has Qtc 0.62, system resonance 54.0 Hz and F3 65.8 Hz. It produces 94.5 dB at 40 Hz under these modelled conditions.

Try the model#

Interactive example

Try the 15 litre box

Change one input and watch both graphs. These curves are recalculated in your browser by the same simulation engine as the main app.

Live simulator output
Fs
32.3 Hz
Qts
0.37
Vas
27.0 L
Xmax
8.8 mm
Pe
150 W
50 W

About 14.0 V RMS from Re. Actual current and delivered power change with impedance.

15 L net, sealedHalf-space at 1 mNo EQ0.1 Ω series resistanceSolver 5–400 Hz · graphs 10–400 Hz
F3
65.8 Hz

Response shape

SPL at 40 Hz
94.5 dB

Half-space, 1 m

Peak shown
7.9 / 8.8 mm

Excursion / Xmax

System Qtc
0.62

Fsc 54.0 Hz

The graph stays below Xmax, but the solver continues down to 5 Hz and reaches 9.9 mm at 5 Hz. If the source contains energy that low, use a suitable high-pass filter or less drive.

SPL response

Power moves the curve up; the driver and box set its shape. Hover or click to read a point.

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15 L sealed-

Cone excursion

Read this beside SPL. The dashed line marks the selected driver's library Xmax.

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15 L sealed-

Continue with this driver and power setting. The simulator will load the same 15 L sealed enclosure so you can add filters, compare alignments and save the design.

Open this setup
The box stays at 15 L. Changing the driver is a comparison, not a recommendation that every driver belongs in this volume.

Read both graphs#

  1. 1

    Increase the power

    Compare 1 W with 100 W. The level at 40 Hz changes from 77.5 to 97.5 dB. F3 stays at 65.8 Hz: more drive changes level, not the alignment.
  2. 2

    Watch the travel

    At 50 W the displayed band peaks at 7.9 mm near 10.1 Hz, against this driver’s 8.8 mm Xmax. At 100 W the peak becomes 11.2 mm. Check the whole operating band.
  3. 3

    Swap the driver

    The box stays the same, but its system Q, resonance and travel change. Compare the bass level and travel together instead of choosing by nominal cone size alone.

Before you cut wood#

  • Build enough internal space for 15 L of air plus the driver, bracing and anything else inside the cabinet.
  • Verify the exact driver data and Xmax. A linear-travel rating is not a guarantee about distortion or mechanical noise.
  • Use the final filter settings and intended drive in the main simulator. Check Max SPL (dB) and Headroom as well as the two graphs here.
  • Measure impedance and acoustic response on the finished box. Room gain, cabinet vibration and sample variation are outside this example.
Open the starting designContinue with the same driver, volume and power in the simulator.

Ask your AI

Using 00 Simulator, inspect my selected sealed enclosure at its current power. Report system Q, F3, cone excursion and the limiting frequencies. Compare a lower power and a high-pass filter without saving either change.
or open it inClaudeChatGPT

Connect your assistant so it can open your designs.

SealedExcursionPower and limitsFrom simulation to a build