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DRIVERSWIRINGIMPEDANCE

Several drivers and wiring

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.

SPL

dB

  • One driver, 15 LF3 62.2 Hz · Level 102.4 dB
  • Two drivers, 15 LF3 65.2 Hz · Level 105.5 dB
  • Two drivers, 30 LF3 60.8 Hz · Level 105.2 dB
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.
DesignPowerF3LevelEach cone at 20 Hz
One driver, 15 L50 W62.2 Hz102.4 dB7.0 mm
Two drivers, 15 L50 W65.2 Hz105.5 dB3.2 mm
Two drivers, 30 L50 W60.8 Hz105.2 dB4.9 mm
Two drivers, 30 L100 W60.8 Hz108.2 dB6.9 mm
Dayton Audio DCS205-4, sealed, half space, 1 m, wired in parallel. Simulated when this page was built.
  • 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:

WiringStringsDrivers per stringShown as
4P411.00 Ω
2S2P224.00 Ω
4S1416.0 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.

Impedance

Ω

  • 2PLowest 2.1 Ω · Load voltage 9.9 V
  • 2SLowest 8.0 Ω · Load voltage 19.7 V
Dayton Audio DCS205-4, sealed, 50 W in total, half space, 1 m. Simulated when this page was built.

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.

Voice coil wiringShown asLowest impedanceLevel
Series3.70 Ω3.8 Ω97.4 dB
Parallel0.93 Ω1.0 Ω97.0 dB
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.

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.

Try it#

Open the sealed example 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.
or open it inClaudeChatGPT

Connect your assistant so it can open your designs.