# Boxes overview

> The box types in 00 Simulator compared with one driver in one 10 L box: sealed, vented, passive radiator and bandpass, and what each is for.

Source: https://simulator.00aud.io/docs/boxes

Every enclosure in 00 Simulator that is not a horn is a box: sealed, vented, passive radiator, bandpass 4 and bandpass 6. What sets them apart is where the air behind the cone can go. This page puts one driver in the same box four ways, so the differences you see are the box’s alone.

## One driver, four boxes

The Dayton Audio DCS165-4 in 10 L, built as each box type in turn, at 1 W:

_Figure: SPL of the Dayton Audio DCS165-4 in the same 10 L as a sealed, a vented, a passive radiator and a bandpass 4 box._

Dayton Audio DCS165-4 in 10 L, every box at 1 W, half space, 1 m. The passive radiator is an SB Acoustics SB15SFCR-00 with 50 g added; the port is tuned to the same 35.4 Hz; the bandpass front is tuned to 60 Hz. Simulated when this page was built.

| Box | −3 dB |
| --- | --- |
| Sealed | from 77.5 Hz |
| Vented, 5 cm port | from 35.9 Hz |
| Passive radiator, 50 g added | from 35.6 Hz |
| Bandpass 4, 5 L + 5 L | 41–90 Hz |

- **Sealed** rolls off first and most gently: −3 dB from 77.5 Hz, falling about 12 dB per octave below that. The air in the box is a spring behind the cone, and only the cone radiates.
- **Vented** and **Passive radiator** both tune the box to about 35.4 Hz and reach down to 35.9 Hz and 35.6 Hz: at 35 Hz they are 6.9 dB and 7.0 dB louder than the sealed box. The port that does it is 43.7 cm long, twice the inside of a 10 L cube (21.5 cm a side); the radiator needs only a hole in the baffle.
- Below the tuning the two part ways: the port’s output keeps falling steeply, the radiator’s drops into a notch at 15.4 Hz, near the radiator’s own resonance with its added mass.
- **Bandpass 4** passes a band, 41–90 Hz. The driver sits between a sealed rear chamber and a ported front one, and only the port radiates, so the upper bass is filtered out: at 200 Hz it is 19.4 dB below the sealed box.

> **One comparison, not a ranking** These four share a driver and a volume so the curves compare fairly. Each type does its best with a box chosen for it: for this driver, the Add enclosure dialog starts a sealed box at 3.6 L and a vented one at 18.2 L. The passive radiator here was picked to match the port. Each type’s page shows what its own settings do.

## The box types

Choose the type in **Type** at the top of the enclosure panel. The two bandpass types show there as **4th-order BP** and **6th-order BP**.

| Type | The air behind the cone | Choose it for |
| --- | --- | --- |
| [Sealed](https://simulator.00aud.io/docs/boxes/sealed) | Trapped in a closed box, as a spring. | Small, simple boxes, a gentle roll-off and tight timing. |
| [Vented](https://simulator.00aud.io/docs/boxes/vented) | Leaves through a port tuned with the box. | Deeper bass from the same box, when the port fits. |
| [Passive radiator](https://simulator.00aud.io/docs/boxes/passive-radiator) | Moves a second cone with no motor, tuned by its mass. | A low tuning in a small box, with no port to chuff. |
| [Bandpass 4](https://simulator.00aud.io/docs/boxes/bandpass-4) | Fills a sealed rear chamber; the front chamber radiates through a port. | A band of bass with the range above it filtered out. |
| [Bandpass 6](https://simulator.00aud.io/docs/boxes/bandpass-6) | Both chambers are ported, each with its own tuning, and only the ports radiate. | A band shaped by two tunings. |

A horn loads the driver with a path that widens to a mouth instead of a box. The eight horn types have their own tab: [Horns overview](https://simulator.00aud.io/docs/horns).

## In every box

- [Ports and end correction](https://simulator.00aud.io/docs/boxes/ports): Port shapes, several ports, end correction and the port model.
- [Several drivers and wiring](https://simulator.00aud.io/docs/boxes/multiple-drivers): More than one driver in a box, and how they are wired.
- [Losses and damping](https://simulator.00aud.io/docs/boxes/losses): The losses a real box has, and what the model includes.

## Where to start

- [Choose an enclosure type](https://simulator.00aud.io/docs/start/enclosure-types) compares the app’s own examples, one of each type, from sealed to horn.
- When you add an enclosure with a driver chosen, 00 Simulator suggests **Sealed** or **Vented** from the driver’s EBP (Fs divided by Qes): vented above 75, sealed at 75 or below.
- The [Sealed box calculator](https://simulator.00aud.io/calculators/sealed-box) and [Ported box calculator](https://simulator.00aud.io/calculators/ported-box) size a first box for a driver before you open the simulator.

## Ask your AI

**Ask your AI**

Your assistant builds and compares the boxes with the same solver, through the 00 Simulator connector.

> Using 00 Simulator, add a sealed and a vented box of the same volume to my open workspace, both with the driver from my first enclosure. Simulate them at its set power and compare their F3, peak excursion and, for the vented box, peak port air speed.