spl Control One

You can listen to your production via two switchable pairs of speakers. A subwoofer is also switched on and off with speaker pair A.

In the middle position of the switch, the speakers are switched off, which is convenient because you don’t have to turn the volume control back.

Two analog stereo inputs can be connected to the Control One for sources such as a DA converter, CD player, mixing console, synthesizer or analog tape machine/tape deck, which can also be listened to mixed together (1+2).

The selected input signal is output unchanged at the Line Out. This allows the Control One to be looped between devices without “losing” an output.

If, for example, several people are to listen in via headphones, a headphone amplifier can simply be connected to the Line Out. You can also record the signal analog or send it to a mixer for further processing.

The output stage of the headphone amplifier is designed as a push-pull amplifier in class AB mode. The bipolar transistors share the amplification of the positive and negative half-waves, which produces a higher gain and a higher output voltage than in Class A operation, where only one transistor amplifies both half-waves.

The output stage transistors are thermally coupled and thus run particularly coherently, which contributes to a consistent and stable sound image.

The power supply has a buffer circuit with low source resistance, ensuring generous current reserves even when driving low-impedance headphones.

The Phonitor Matrix in its largest expansion stage has three parameters: Crossfeed, Speaker Angle and Center Level.

In the Control One, the center level is preset to -1 dB and the speaker angle to 30°. These are the most commonly used values. The crossfeed function determines the so-called interaural level difference. The intensity of the crossfeed is fully variable. At the beginning of the control path the crossfeed circuit is not in the audio path. Dialing the control in switches on the crossfeed circuit via relay (hysteresis circuit). The audio signal therefore does not pass through the crossfeed stage if this is not desired.

Good sound always starts with the power supply. This is where you lay the foundation for the performance of the entire device.

The Control One delivers full power when used with the included 1.5 A power supply. Only use the 12 V plug-in power supply unit within the scope of delivery. The ON-switch puts the Control One into operation.