Crossover Use

Do you require a crossover?

Without a crossover the subwoofer will provide very high quality reproduction of the Low Frequency Effects (LFE), or “point 1”, channel of a multi channel sound system.

When used with a crossover, the subwoofer can, in addition, also reproduce the low frequency part of the main channels in a 2 channel or multi channel music or video sound system. It is desirable to use the subwoofer in this capacity if the main speakers do not reproduce the entire bass range or if the main speakers cannot play at the volume level desired without distortion. Depending on your requirements, the crossover can be either the bass management capabilities of a sound processor, one of our dedicated passive crossovers, or the SmartSub Integrator. Here is a description of each of these with their advantages.

Crossover Types Compared

Crossover type	Integration	Flexibility	XO mode?
Processor	Poor	Low	Yes
Passive XO	Very good	Low	No
Integrator	Excellent	High	Yes

Processor Bass Management

Surround sound processors have the ability to redirect the bass energy away from your main speakers and into the subwoofer channel where it is reproduced by the subwoofer, with the benefits of allowing the main speakers to play louder than they otherwise would, and the bass to be reproduced better. This is implemented by telling the processor that your main speakers are “small”.

The limitation of this bass management approach is the poor balance and integration between the subwoofer and the main speakers that the processor’s generic filters provide. It may be suitable for low standard video systems and will seldom be suitable for music.

THIEL Passive Crossovers

There are several passive crossovers available that match a THIEL subwoofer to various THIEL speaker models. Since they are designed for specific models, they achieve very good integration and balance between the subwoofer and the main speakers. Also, being passive, they are of quite reasonable cost. They allow the subwoofer to augment the main speakers in the precise way that will enable the combination of main speaker and subwoofer to produce perfectly balanced and blended sound with the bass range extended to below 20 Hz. Two passive crossovers can be used with two subwoofers to provide stereo bass reproduction.

A limitation is that these crossovers do not redirect bass energy away from the main speakers and so the main speakers will not play any louder than otherwise.

This is often an ideal system for music systems and a good approach for video systems when the main speakers play sufficiently loud but do not have extended, deep bass response.

THIEL SmartSub Integrator

The SmartSub Integrator provides a high level of flexibility, universality, and functionality. It provides near- perfect integration with any main speakers, regardless of brand. It can be used both in augment mode, where the subwoofer extends the bass range of the main speakers, and in crossover mode. In crossover mode the built-in high pass filter transfers bass energy away from the main speakers and redirects it to the subwoofer, so that the main speakers are able to play louder. The Integrator also allows adjustment of crossover frequency, LFE level and separate adjustment of main channel bass extension and low frequency level. In addition, it can control stereo subwoofers, and be used to control systems with up to 16 subwoofers.

This is a complete, no-compromise approach with no limitations.