X-Load Reactive Load LB-2

The information on this page supplements the official manuals.

About the X-LOAD LB-2 load box

Product information:

"The LB-2 is a passive load box that replicates the complex impedance of a guitar loudspeaker. It features our Dynamic Impedance Technology, which delivers unprecedented realism by dynamically changing the impedence of the load depending on the power levels of the connected amplifier."

"The X-Load LB-2 Load Box represents the pinnacle of speaker emulation technology for live use or recording. It allows you to use a traditional tube amp without connecting a speaker cabinet. The X-Load LB-2 provides an 8Ω load (100W maximum) while outputting a balanced or unbalanced line level signal.

Unlike other load boxes and attenuators the X-Load LB-2 uses Fractal Audio Systems' Dynamic Impedance technology to create a level of realism never achievable before. Record your amp in its sweet spot without deafening volume, or get great tone consistently without the hassles of a speaker cab and microphone setup.

It is important to note that the X-Load LB-2 does NOT simulate the characteristic sound of a loudspeaker. This is done by routing your DI Amp signal through speaker simulation hardware—like that found in our award-winning Axe-Fx or AX8 products—or software, like our Cab-Lab application/plugin.

The X-Load LB-2 features a Speaker Thru jack so you can connect a real speaker while also feeding line signal to a recorder or speaker simulator.

The Voicing switch shifts the resonance of the load. The “UK” setting is characteristic of the typical British guitar speaker, while the “US” position replicate the lower resonance of a typical American guitar speakers.

Read the Owner's Manual.

How to make use of the X-LOAD

As a silent load box/DI

• Connect your amplifier’s 8-ohm output to the Amp In jack on the rear of the LB-2.
• Connect either the Unbalanced or Balanced DI output to your audio interface or hardware cabinet emulator.

As a DI with guitar speaker

• Connect your amplifier’s speaker output to the Amp In jack on the rear of the LB-2.
• Connect a speaker to the rear panel Speaker Thru jack.
• Connect either the Unbalanced or Balanced DI output to your audio interface or hardware cabinet emulator.

As an attenuator

The LB-2 can be also be used to reduce the volume of your amp by diverting half the power into its load.

• Connect one 4 ohm output of your amp to an 8 ohm speaker.
• Connect the other 4 ohm output to the LB-2 Amp In jack.

This will present two 8 ohm loads in parallel to your amp which is equivalent to a 4 ohm load. Half of your amp’s output power will go the speaker and the other half into the LB-2 reducing the volume of your amp by 6 dB. You can also use the DI features of the LB-2 in this configuration.

Warnings

The LB-2 is an 8 ohm device. Be sure to connect its Amp In jack to the proper output on your amplifier to avoid damage. Mismatching impedance can result in damage to your amp.

The maximum power rating of the LB-2 is 100W. Do not connect the LB-2 to any amplifier that is rated greater than 100W as this can damage the unit and/or the amp.

Front panel

• DI LEVEL: this controls the DI output volume of the LB-2 at both the Unbalanced 1/4” and Balanced XLR jacks. Set this knob as required so as not to overdrive the input of a device connected to the DI Output of the LB-2.
• VOICING: a tube amp interacts differently with different types of speakers. The voicing switch of the LB-2 changes the resonance of its load to simulate this. The “UK” position simulates a classic British guitar speaker. The “US” position lowers the resonance frequency to replicate the experience of playing through a classic American guitar speaker.

Rear panel

• AMP IN: connect the speaker output of your tube amp to this jack. The X-Load LB-2 is an 8-ohm (8Ω) device with a maximum power rating of 100W.
• SPEAKER THRU: Connecting a speaker to this output jack disconnects the internal load and connects the Amp In jack to the speaker instead. The DI output will still be active so you can simultaneously record or process the DI signal while using your amp with a real speaker.
• WARNING: never connect Speaker Thru to any mic, instrument or line-level inputs!
• UNBALANCED DI/LINE OUTPUT: (1/4”) This passive DI output provides a line-level signal.
• BALANCED DI/LINE OUTPUT: (XLR) This active DI output provides a line level signal. For long cable lengths and maximum delity the XLR output is preferred as it provides a low- impedance output and immunity to noise conduction. This output requires that the X-Load LB-2 be powered in one of two ways:
  1. Connect an external power supply to the power input jack of the X-Load LB-2. Use a 9–24 VDC, center negative power supply (as typically used with “stomp boxes”).
  2. Or: Supply phantom power via the connected XLR cable.
• GROUND LIFT: This switch disconnects the ground of the X-Load LB-2 from the ground of the XLR output. This may help in breaking noisy ground loops.

Speaker output

For maximum versatility, the X-Load LB-2 can be used with or without a connected speaker. This allows you to use a speaker simulator for recording of front-of-house while operating either silently or at normal levels. The X-Load LB-2 does NOT emulate the sound of a loudspeaker. It outputs a line-level version of the signal your amplifier normally sends to a connected speaker. This must be processed to sound as if it has been through a speaker and microphone—typically using software like Fractal Audio Cab-Lab or a hardware solution like the Fractal Audio Axe-Fx II, AX8, or 3rd party “speaker simulator” products.

More information about the X-LOAD

Forum threads:

• http://forum.fractalaudio.com/threads/in-the-spirit-of-namm-anouncements.123378/
• http://forum.fractalaudio.com/threads/recording-tube-head-with-axe-fx-cab-sims.119956/#post-1427584
• http://forum.fractalaudio.com/threads/fractal-load-box-d.120414/#post-1433284
• http://forum.fractalaudio.com/threads/in-the-spirit-of-namm-anouncements.123378/page-8#post-1486352