Filter Type, Delay | Lyngdorf Audio DPA-1 manual

In general, the recommended crossover frequency between (sub)woofers and main speakers is be- tween 200 - 400 Hz.

By using a high crossover frequency, the rear wall quarter wavelength reﬂection is removed from the main speakers.

If a Lyngdorf Audio boundary woofer is used in a 2+2 set-up, a crossover frequency of 400 is recom- mended due to the high bandwidth of the boundary woofer.

For conventional active subwoofers with built in low pass ﬁlter the recommended crossover frequency is the upper low-pass frequency of the subwoofer.

If at all possible, the low pass ﬁlter in the subwoofer should be bypassed. Due to the quarter wave reﬂection from the rear wall corresponding to the depth of the subwoofer cabinet we recommend an crossover point at approximately 200 Hz. You might experiment with turning the subwoofer so the driver faces the wall in a distance of 5 to 10 cm. This will increase the bandwidth of the subwoofer.

However, due to the limited bandwidth (frequency response) of most conventional subwoofers you might ﬁnd it necessary to choose a lower crossover frequency.

When ‘building’ active speaker systems it is recommended to use the original crossover point(s) used by the manufacturer. Due to the short wavelengths of the mid/high frequencies it is essential that both crossover frequency, ﬁlter type and order as well as delay is set correctly. Therefore, creating ﬁlters for active speakers is an iterative process that requires several critical listening sessions in order to achieve seamless integration of the different speaker drivers.

Filter Type

Filter Type is only available when Routing has been setup.

It is possible to choose from two different Filter Types in this menu.

LiRi: (Linkwitz Riley) 2, 4 or 8 order.

Butw: (Butterworth) 1, 2 or 4 order.

In a 2+2 set-up (main speakers + Lyngdorf Audio boundary woofers) we recommend using a fourth order Linkwitz Riley ﬁlter.

In set-ups using conventional active subwoofers – again due to limited bandwidth – we recommend us- ing a second order butterworth ﬁlter.

In active speaker systems it is recommended starting with a fourth order Linkwitz Riley ﬁlter.

Delay

If you are using a set-up with two main loudspeakers located at an identical distance to the listening position you don’t need to set a delay. However, if the distance isn’t identical and/or you are using a sub- woofer, or a Lyngdorf Audio 2+2 system, you need to set a delay in order to ensure that the sound from each loudspeaker reaches the listening position simultaneously. This must be done for main left (ML) and right (MR) and as well as line left (LL) and right (LR).

To set the delay all you need to do is measure the distance from each loudspeaker to the listening posi- tion and enter these values in the menu. The necessary delays are then automatically calculated and applied to each channel.