# Several drivers and wiring > Several identical drivers in one 00 Simulator enclosure: what the box, the power and the load share, how wiring changes the impedance, and dual voice coils. Source: https://simulator.00aud.io/docs/boxes/multiple-drivers One enclosure can hold several identical drivers. Set **Number of drivers** and they share the box’s air and its power; set **Wiring** and only the load the amplifier sees changes. This page shows both on the sealed example, and how dual voice coils work. ## Number of drivers **Number of drivers** sits under **Driver** in the enclosure panel and takes 1 to 50. Every driver is the model you chose, all in the same box. The **Input power** under **Power** is the total: 00 Simulator gives each driver an equal share, and adds up what their cones move. _Figure: The sealed example with one Dayton Audio DCS205-4, with two in the same 15 L and with two in 30 L, all at 50 W in total._ Dayton Audio DCS205-4, sealed, 50 W in total, half space, 1 m. Simulated when this page was built. Level is the loudest one-octave average. | Design | F3 | Level | | --- | --- | --- | | One driver, 15 L | 62.2 Hz | 102.4 dB | | Two drivers, 15 L | 65.2 Hz | 105.5 dB | | Two drivers, 30 L | 60.8 Hz | 105.2 dB | Dayton Audio DCS205-4, sealed, half space, 1 m, wired in parallel. Simulated when this page was built. | Design | Power | F3 | Level | Each cone at 20 Hz | | --- | --- | --- | --- | --- | | One driver, 15 L | 50 W | 62.2 Hz | 102.4 dB | 7.0 mm | | Two drivers, 15 L | 50 W | 65.2 Hz | 105.5 dB | 3.2 mm | | Two drivers, 30 L | 50 W | 60.8 Hz | 105.2 dB | 4.9 mm | | Two drivers, 30 L | 100 W | 60.8 Hz | 108.2 dB | 6.9 mm | - Double the drivers and the box together and the shape stays: F3 moves from 62.2 Hz to 60.8 Hz. At the same 50 W the pair is 2.8 dB louder while each cone moves 0.70 times as far, because each gets half the power. - Give the pair twice the power too and it is 5.8 dB louder, with each cone moving as far as the one did. - Two drivers in the same 15 L share its air, so each sees half the box: the level rises 3.1 dB, but the deep bass gains less and F3 rises to 65.2 Hz. - Limits are per driver: the **Excursion** tile shows one cone’s travel against its Xmax. - In a sealed box the **system resonance** and **system Q** fields count every driver. **Driver displacement**, under **Box volume adjustments**, is one figure for the box: enter all the drivers’ displacement together. ## Wiring **Wiring** appears once there are two or more drivers. It lists the balanced ways to wire the count you set: S is drivers in series, P is parallel strings, so 2S2P is two series pairs wired in parallel. Each option shows the nominal load the amplifier sees. For four of the example’s drivers: | Wiring | Strings | Drivers per string | Shown as | | --- | --- | --- | --- | | 4P | 4 | 1 | 1.00 Ω | | 2S2P | 2 | 2 | 4.00 Ω | | 4S | 1 | 4 | 16.0 Ω | The acoustic output is the same for every option: 00 Simulator drives each driver from its share of **Input power**, so the wiring only changes the voltage and current the amplifier supplies. **Load voltage** under **Power** shows the voltage: 9.9 V for two drivers in parallel at 50 W, 19.7 V in series. _Figure: The impedance the amplifier sees from two Dayton Audio DCS205-4 drivers in 30 L, wired in parallel (2P) and in series (2S)._ Dayton Audio DCS205-4, sealed, 50 W in total, half space, 1 m. Simulated when this page was built. | Design | Lowest | Load voltage | | --- | --- | --- | | 2P | 2.1 Ω | 9.9 V | | 2S | 8.0 Ω | 19.7 V | > **Series resistance is the exception** **Series resistance**, the cable and amplifier’s own resistance, sits at the amplifier’s terminals, so it takes a bigger share of a lower load. At the default 0.1 Ω the parallel pair above is 0.3 dB quieter than the series pair, and its F3 is 60.8 Hz against 63 Hz. Changing **Number of drivers** to a count the current wiring does not divide sets the wiring back to all in parallel. The **Impedance** and **Amplifier Load (VA)** tiles show what the amplifier sees across the band. ## Dual voice coils **Voice coil wiring** appears when the driver has two voice coils: **Series** or **Parallel**, each shown with its resistance. The simulation treats a dual-coil driver’s stored Re, Le and Bl as values for the coils in series. **Parallel** divides the resistance and the inductance by 4 and the force factor by 2, so the load is a quarter and the output at the same power is the same, again apart from series resistance. Dayton Audio UM10-22 in the 60.8 L sealed box the **Add enclosure** dialog starts it in, at 50 W, half space, 1 m. Simulated when this page was built. | Voice coil wiring | Shown as | Lowest impedance | Level | | --- | --- | --- | --- | | **Series** | 3.70 Ω | 3.8 Ω | 97.4 dB | | **Parallel** | 0.93 Ω | 1.0 Ω | 97.0 dB | With several dual-coil drivers the two settings multiply: the coil wiring sets each driver’s load, and **Wiring** combines the drivers. ## Different drivers A box holds one model of driver. A multiple-entry horn is the exception: each of its drivers can use a different model, with its own count, wiring, power and EQ. To compare different drivers in boxes, give each its own enclosure in the workspace. Passive radiators have their own count, **Number of PRs**, also up to 50. - [Multiple-entry (MEH)](https://simulator.00aud.io/docs/horns/multiple-entry-horn): Several drivers on one horn path. - [Compare designs](https://simulator.00aud.io/docs/guides/compare): Several enclosures on the same tiles. - [Power and limits](https://simulator.00aud.io/docs/guides/power-and-limits): Input power, series resistance and the limits it runs into. ## Try it [Open the sealed example](https://simulator.00aud.io/app?template=sealed&power=50) at 50 W, set **Number of drivers** to 2 and **Volume** to 30 L, then switch **Wiring** between 2P and 2S and watch the **Impedance** tile. ## Ask your AI **Ask your AI** Your assistant runs the same solver on your own designs through the 00 Simulator connector. > Using 00 Simulator, take the sealed box in my open workspace and, without saving, try two of its driver in twice the volume, wired in parallel and in series. For each option tell me the F3, the level at 100 Hz, each cone’s peak excursion and the lowest impedance at the saved power.