DLS Svenska AB NOBELIUM 12 manual Welcome, Connection of Subwoofer, Subwoofer ENCLOSURES, General

ULTIMATE Nobelium

SERIES SUBWOOFERS

*Nobelium is a radioactive metal with atomic number 102. It is named after the Swedish scientist Alfred Nobel

Nobelium 10

Nobelium 12

Nobelium 15

WELCOME

Thank you for buying a DLS ULTIMATE Nobelium subwoofer. The subwoofer must be installed correctly in order to work well. This manual will show you how to install it like a pro. Please read the entire manual before beginning the installation.

Install the subwoofer yourself if you feel confident with our instructions and if you have the proper tools. However if you feel unsure, turn over the installation job to someone better suited to it.

The speakers are designed for enclosure mounting. In "open air" installations the power handling capacity is reduced by 30% from the nominal value. We dont recommend ”open air” installations for Ultimate Nobelium subwooers.

CONNECTION OF SUBWOOFER

How to connect depends on what type of amplifier you use. The best is to follow the instructions given in the manual for the amplifier. Most amplifiers today have built-in lowpass crossover and possibilities to connect your subwoofer in bridge mode.

Two 4 ohm subwoofers are often connected in stereo mode since most amplifiers can´t handle bridge mode loads below 4 ohms.

The Iridium subwoofers have dual, four ohm, voice coils. Each voice coil has an impedance of 4 ohms. If they are connected in series the resulting impedance is 8 ohms. If they are connected in parallel the resulting impedance is 2 ohms. Make sure to connect in a way that don´t ruin the amplifier. If you have a DLS Ultimate amplifier it´s possible to connect the voice coils in parallel, these ampliers are 1 ohm stable.

We also recommend the use of a subsonic highpass filter. This gives a better bass reproduction with less "rumble". In most DLS amplifiers this feature is already built-in.

For wiring use high class speaker wires, min AWG13 (2.5 mm2). For example DLS SC 2x4.

If you have an amplifier without built-in crossover you must use a passive crossover between amplifier and subwoofer like in this example, one crossover for each voice coil.

Component values are for 4 ohms.

+
	L	C
-
Connected with a 12 dB passive low-pass x-over = 10 mH coil
in series and a bipolar capacitor of 300 microFarad in parallel.
Crossover frequency is 95 Hz.

23456

Active filter Amplifier

SUBWOOFER ENCLOSURES, GENERAL

Build your enclosure in a stable and airtight material. The best is MDF-board, 19 mm, or particle board, 22 mm. Larger enclosures must have bracing inside to avoid vibrations. The enclosure must be completely airtight. Use sealing compound in all joints, also around the cable terminals. The size of the enclosure is decided by the speaker data.

SEALED ENCLOSURES

Sealed enclosures are easy to build. The size is not critical, but it can´t be too small. The speaker data such as Fs, Qts, Vas and X-max decides the size of the enclosure.

Large speakers need larger boxes. Two speakers need a box of the double size etc. The enclosure must be completely air- tight.

A sealed enclosure should be filled with acoustic wool up to 75 - 100%.

A sealed enclosure has a lower efficiency than vented enclosures but they can handle high power and are easy to build.

A subwoofer in a sealed enclosure creates a tight bass suitable for the audiophiles listening to classical music, jazz and soft rock. The Nobelium subwoofers can be used in sealed enclosures.

VENTED ENCLOSURES

A speaker in a vented enclosure has a higher efficiency (3 dB) and higher power handling capacity than in a sealed enclosure. In a vented enclosure the sound from the speaker and the port work together creating a higher sound level. The sound from the port must come out in the same phase as from the speaker otherwise the result is bad.

The size of the vented enclosure is decided by the speaker data just as for the sealed one.

The size of the vehicle often decides the practical size of the enclosure. A smaller enclosure has a higher resonant frequency than the larger one. The size of the enclosure should not be so big that the speaker plays below it´s own free air resonance (Fs), if so the power handling capacity drops.

The port does not have to be fully inside the enclosure as long as the area and length are correct. Sometimes you need two or more ports in an enclosure. You can convert from one to two or more ports as long as the total port area is the same.

All Nobelium subwoofers can be usedl in vented boxes.

BANDPASS ENCLOSURES

In all bandpass enclosures the speakers are hidden inside the enclosure, all sound is coming out through the ports. There are different types of bandpass enclosures and they have in com- mon that they are a bit more difficult to build. DLS Iridium subwoofers can be used in bandpass enclosures.

IMPORTANT!

Think of the speaker weight when you install it. If you don´t mount it properly it can come loose.

Connection in mono bridge mode with an active x-over. Voice coils connected in series. If you have a 1 ohm stable amplifier the voice coils should be connected in parallel for best performance (for example on a DLS monoblock).

Valid from 2005-07-04