Always consult the Owners Manuals

X-Load load boxes

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About the X-Load LB-1

Image to be added

The LB-1 has not yet been released yet by Fractal Audio.

"The LB-1 will be a load box with integrated IR player." source
"There are two models. The LB-1 is a full-featured product that includes stereo IR processing plus effects and a whole lot more (I don't want to spill the beans yet)." source

About the X-Load LB-2


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.

"The idea is that you use this with any of our products that have cab modeling (Axe-Fx, AX-8, Cab-Lab). Some people refuse to use modelers so this is a product for them." source
"The load itself uses proprietary, custom-designed magnetics that mimic the dynamic impedance of an actual loudspeaker. I've been testing the passive version and it sounds much better than any other loadbox I've tried. No high end loss and nice, chunky bass response." source
"The impedance of our load actually resembles a real speaker. The same can't be said about some of the other so-called "reactive loads". Furthermore I've developed proprietary magnetics technology so the impedance changes with applied voltage, like a real speaker does. Most importantly though, it sounds really good. I'd go so far to say it sounds better than when I use my iso cab as a load.” source
"A real speaker resembles a 4th-order network, at a minimum. Our load is 4th-order." source
"It's just a load box. There are several others on the market: Suhr, Torpedo Captor, etc. Ours sounds really good. I haven't tried the others so I can't comment but Suhr makes good stuff so I don't doubt their's sounds good. You can use the load box with any product that does speaker emulation including our Axe-Fx, AX-8 and Cab-Lab products or other products (like plug-ins) allowing you to record your favorite amp without the noise and hassles of micing a speaker. Furthermore this allows you to record a DI that you can reprocess later using different IRs. While the frequency response of a speaker to a voltage excitation is very linear and can be accurately captured by an IR, the various parameters of a speaker change with applied power. First of all the voice coil heats up and as a result it's resistance increases [1]. Secondly the equivalent inductance of the voice coil and the resonance frequency of the speaker change with excursion (see Dodd, Klippel, et. al.). Our load recreates these parameter changes that occur with excitation level using proprietary magnetic components (not magnets) which are made in USA." source
"The LB-2 is about 50/50 foreign and domestic content. source

Important 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.

How to make use of the X-Load LB-2

As a silent load box and DI

As a DI with guitar speaker

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.

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.

“You can use our reactive load as an attenuator by running your amp at 4 ohms. Plug your speaker into one jack and the load into the other. Half the amp's power will go to the speaker and the other half to the load. Not a huge reduction in volume but might tame things enough so you don't piss of your neighbor/wife/GF/mother-in-law/etc.” source

Controls on the X-Load LB-2

Front panel


Rear panel

LB-2 rear.jpg

WARNING: never connect Speaker Thru to any mic, instrument or line-level inputs!

"If your XLR has phantom power you don't need a wall-wart. The active outputs provide a low-impedance buffered output without the coloration (and cost) of a transformer." source

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.

Size of the X-Load LB-2


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