With the IPD "Intelligent Power Drive" series, Lab.gruppen has created a new concept for the amplification of medium-power sound reinforcement systems that incorporates a DSP platform and intelligent power management into an affordable 1U rack sized package, which is light and easy to set up.
To do this, the Swedish manufacturer has changed its tune in amplification technology by opting for fully bridged class D instead of class TD (tracking class D) and is working on the optimal management of energy resources of the switch-mode power supply (without PFC) by distributing the available energy between the two channels as required.
The IPD series currently consists of two models: IPD 1200 and IPD 2400, which, as their names suggest, are capable of delivering a power of 2 x 600 W or 2 x 1200 W into 4 ohms, with both channels operating simultaneously. As we will see further on, in the tests, this refers to a peak power and not an average continuous power (RMS), but that meets the needs of program material with a crest factor*, depending on the type of music, that varies between 8 dB and 20 dB.
Overview
The front panel
The front is uncluttered, as the features of the front panel are contained in the obligatory, relatively ample area of one rack unit. In addition to the lateral handles for rack mounting, there are two ventilation openings: viewed from the front, the one on the right is the air inlet and on the left is the discharge. At the center is the blue LCD display (not always very visible in daylight, so adjust the contrast), framed on the left by navigation buttons (menu and back) and by the mute buttons (one per channel) with their green indicators.
These indicators turn red in case of clipping at the input (pre-mixer). To the right of the display are the LEDs that indicate the activation of the limiters and the rotary encoder for selecting and configuring parameters. Pressing this encoder also provides the confirm/set function. The standby button (ON/OFF) with its LED is located under the display.
The rear panel
The IPD series amplifiers have two balanced analog inputs with link outputs and an AES/EBU input (2 channels) also with link (and automatic switch-over). In the case of a complete connection, the AES inputs can take control if something goes wrong or there is signal loss on the analog inputs. This is an interesting operational fail-safe. Similarly, the output connections are via SpeakOn (1+/1-) for each channel but are also available on binding post terminals for stripped wires respecting the Low Voltage Directive. These also accept standard banana plugs.
The NL4 SpeakOn 1 connector is fully wired for 1+/1- and 2+/2-, with the output of the two channels. All configurations are thus possible, which corresponds to the operating flexibility of these products, suitable for both fixed or temporary installation and touring with small sound reinforcement systems. Be aware that the channel outputs are already bridged with a peak deviation of about 100 V and, therefore, impossible to bridge (so you should not try this).