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Which IR Box Is 4U?

Four top speaker-emulators from Mesa/Boogie, Two Notes, Boss, and Universal Audio

Four top speaker-emulators from Mesa/Boogie, Two Notes, Boss, and Universal Audio get the PG review-roundup treatment.

Guitarists have searched for ways to capture big amp tones at low volume since time immemorial, or at least for the last few decades. The quest became more urgent during COVID, as many of us needed to carve out sonic space for remote-schooled kids, telecommuting roommates, and housebound neighbors griping about loud music, not just on evenings and weekends, but 24/7.


Fortunately, solutions are legion: hardware amp emulators, faux-amp plug-ins, and—our focus here—load box/speaker emulators that let you capture the sounds of your favorite amps minus their usual volume. In fact, we're zeroing in on one particular type of product: load box/emulators that faithfully mimic the sound of a miked speaker via impulse responses.

Impulsive Behavior

Speaker impulse responses (IRs) are created by running a test signal through a cabinet and recording the results. The software then compares the raw signal to the sound that emerges from the speaker, and imposes the same coloration on raw, direct-from-amp tones.

Meanwhile, the load box makes your amp "think" it's connected to a speaker. (Running an analog amp without a speaker load is a quick way to destroy the amp.) The four devices examined here include speaker-out jacks, so you can play through your speaker at reduced levels if desired while simultaneously capturing the direct IR sound. All four offer attractive faux-speaker sounds. Beyond that, prices and features vary dramatically.

While we're specifically examining stand- alone devices, it's also worth noting that amp manufacturers—among them Revv, Fender, Victory, and Mesa/Boogie—are increasingly offering built-in cab IR tech, too.

During COVID, many of us needed to carve out sonic space for remote-schooled kids, telecommuting roommates, and housebound neighbors griping about loud music—not just on evenings and weekends, but 24/7.

About the Demo Clips

I recorded all clips using a ReAmp, so I could run the identical material through each device without having to worry about performance inconsistencies. Each device is represented by three clean tones and three distorted tones. All were recorded through a Carr Lincoln amp, a Vox-inspired boutique model. The test guitars are a pre-CBS Fender Stratocaster for the clean tones and an '80s Gibson Les Paul with retro-style PAFs for the crunchy ones.

Exercise caution when making direct sonic comparisons. The available models and effects vary from device to device. Also, since the Mesa CabClone IR+ has no effects, its clips lack the fattening compression and rich ambience of the rival examples. But CabClone users can easily add those effects within the DAW or at the mixing desk. Finally, remember that only the speaker/cab sound is under review, not the amp tone. Results vary immensely depending on your amp of choice. For example, you may not dig the vintage-flavored tube distortion heard here, but connecting a modern, high-gain amp would instantly yield modern, high-gain tones.

We'll proceed in ascending order of price.

Two Notes Torpedo Captor X Reactive Load Box DI and Attenuator

Two Notes Torpedo Captor X Reactive Load Box DI and Attenuator

Read the review.

Mesa CabClone IR+ Reactive Load Attenuator & IR Cab Simulator

Mesa CabClone IR+ Reactive Load Attenuator & IR Cab Simulator

Read the review.

Boss WAZA Tube Amp Expander Amplifier Attenuator

Read the review.

OX Me Again: Revisiting Universal Audio’s Amp Top Box

Universal Audio\u2019s Amp Top Box

Read the review.

Another day, another pedal! Enter Stompboxtober Day 7 for your chance to win today’s pedal from Effects Bakery!

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A twist on the hard-to-find Ibanez MT10 that captures the low-gain responsiveness of the original and adds a dollop of more aggressive sounds too.

Excellent alternative to pricey, hard-to-find, vintage Mostortions. Flexible EQ. Great headroom. Silky low-gain sounds.

None.

$199

Wampler Mofetta
wamplerpedals.com

5
5
5
4.5

Wampler’s new Mofetta is a riff on Ibanez’s MT10 Mostortion, a long-ago discontinued pedal that’s now an in-demand cult classic. If you look at online listings for the MT10, you’ll see that asking prices have climbed up to $1k in extreme cases.

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Although inspired by the classic Fuzz Face, this stomp brings more to the hair-growth game with wide-ranging bias and low-cut controls.

One-ups the Fuzz Face in tonal versatility and pure, sustained filth, with the ability to preserve most of the natural sonic thumbprint of your guitar or take your tone to lower, delightfully nasty places.

Pushing the bias hard can create compromising note decay. Difficult to control at extreme settings.

$144

Catalinbread StarCrash
catalinbread.com

4
4
4
4


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Intrepid knob-tweakers can blend between ring mod and frequency shifting and shoot for the stars.

Unique, bold, and daring sounds great for guitarists and producers. For how complex it is, it’s easy to find your way around.

Players who don’t have the time to invest might find the scope of this pedal intimidating.

$349


Red Panda Radius

redpandalab.com

5
5
4
4


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