REACTIVE LOADBOX WITH IR LOADER AND ATTENUATOR
React:IR – is a reactive-resonance load box, attenuator and impulse loader with length up to 190 ms.
What do “reactive”, and “resonance” mean, and why is it important?
Let`s figure it out, what means reactive, resonance and why it`s important…
Valve (tube) guitar amplifiers have relatively large output impedance due to the output transformer. The guitar cabinet represents a complex reactive load to the amplifier and drastically affects the frequency characteristic of output signal. Adding to this, the majority of guitar amplifiers have negative feedback. This means that some part of output signal returns again to the input of the power amplifier and mixes with the main signal.
Thus, when we speak about a load box, it's important to understand principles of the device's operation and its influence on signal. Guitar speaker manufacturers often publish the impedance curves of their respective products. Usually, guitar speaker have their largest impedance at lower frequencies around 70-90 Hz. When inside a cabinet, the peak at low frequencies resides slightly higher, for example, in 4x12 cabinet, the peak is located around 100-115 Hz due to the cabinet construction. Thus it's important to reproduce not only speaker characteristics, but also the characteristics of the entire cabinet.
Auxillary input for connecting external sources like players, smartphones etc.
Impulse loader input level
5-segment input indicator, for optimal result adjust input level to be in yellow/orange zone, not exceeding red segment.
Output clipping/input signal presence indicator. When Clip indicator lit green, signal is present at input, when clipping occurs at output of impulse loader, indicator switches to red.
Menu button, press to enter menu.
Back button, press to return to previous menu level.
Control dial. Rotate to navigate or change parameter, press to select or set.
Load mode switch
Fan, do not block air flow for proper ventilation.
Historically, different equipment manufacturers have produced different types of load boxes. Initially, a simple passive type of load is used. Then, reactive types were introduced. However, the term, “reactive”, can refer to only high frequency component without low frequency component. Thus, the term, "reactive-resonance”, load was introduced which means correction not only of high frequencies, but also low frequencies. The graph below represents the influence of different load types on frequency characteristics of signal.
React:IR allows usage of all three regimes: passive, reactive and reactive-resonance. The respective modes can be set using switches in the Loadbox section on the front panel of the device.In addition, the device has attenuator, which allows the usage of an amplifier at maximum volume, while listening at quiet “TV” loudness.
React:IR has a number of FX-effects:
Tone Stack emulation can be used in when running a distortion stompbox directly into the line input, for emulation of frequency response of guitar amplifier clean channel.
Impedance Curve emulation can be used for guitar preamp connection into line input, in this case frequency response modified to emulate connection trough guitar power amp.
About power rating of React:IR:
React:IR is nominal 8 Ohm 100W loadbox. What does it mean? It's mean that is 100W of distorted (high gain) signal can be sent to loadbox. It's equivalent to ~150W of sine signal. One need to understand : when you set up master of amplifier to 12 o'clock you get ~12% of power. After 12-13 o'clock of master knob, phase inverter begin to overload. And it's sound more fuzzy for high gain signals. That's why players with high gain don't like to overdrive power amp section and use master knob up to 12-13 o'clock. Another case it's crunch and clean tones ( both are crunch -) ). They use overload of phase inverter for get more tasty tone. There are more higher dynamic diapason called headroom. There are many amps on a market with power more than 100W - Triple Rectifiers, 5150 family, Herbert and others... What will happen with React:IR when using it with this amps? Nothing! It will work properly. But device can be more warm, fan will work on maximum speed. If use master volume up to 12-13 o'clock - you can use any tube guitar amp up to 200W without any limits.
ADC and DAC characteristics:
Download latest software bundle :
Include versions for Win32, Win64, MacOS and Firmware
Dimensions & weight
Equipment and packaging
Input impedance : 8 Ohms
Admissible power : 100W RMS