One of the reasons that players love tube amps is because of how inherently characterful they are, especially when driven and pushed in just the right way to just the right limits. But they can become problematic when you're after that tonal sweet spot in a place or under circumstances that can't accommodate the required volume.
This is where attenuators come in.
An attenuator is a piece of gear that goes between your tube amp's output and speaker to mitigate volume without sacrificing that sweet-spot character. Of course, connecting between the amp's output and speaker is easily done with an amp-and-cabinet rig, but if you have a combo amp, just check for a cable running from the back of your amp to its internal speaker. Often, you can easily unplug that cable and plug in an attenuator in between.
Attenuators come in a variety of styles, at different price points and with unique feature sets. In the video above and throughout the guide below, we highlight some of the best attenuators on the market to help you find what's right for you.
Important note: Look to get an attenuator that can handle double the wattage of your amp, so that you don't risk overpowering the attenuator and frying it, especially when using a reactive attenuator.
Attenuators Featured in the Video
Resistive Attenuators
Attenuators have been around since the 1970s, and the first models were purely resistive. Resistive attenuators work by using a network of resistors that takes in the amp's power, saves some for your speakers, and releases the extra energy as heat. Because of their simplicity, these attenuators are common and generally more affordable than more complex reactive types (more on those in a minute).
Critics of the resistive load system say that the units' method of operation tends to impact and change the amp's tone—usually to something more compressed and dark-sounding—which makes them less-than-ideal if you're not looking to color your amp's tone at all. But for many players, resistive attenuators are perfect for their needs and just as capable as higher-priced and higher-hyped units. If you're new to attenuators and are just looking to see what kinds of tones are possible, any of these resistive attenuators are great options.
Some units give players a little bit of each, like the popular THD Hot Plate attenuators, which are resistive but become reactive when players engage the Deep switch.
Reactive Attenuators
Reactive attenuators are a bit more complex, containing a system of resistors and capacitors designed to actually imitate the impedance curve of a speaker. In this way, it maintains your amp's impedance curve while loading down the output, which results in a more faithful representation of your amp's tone.
Because of their more complex design, these systems are usually more expensive than their resistive counterparts. But if it tonal accuracy is your top priority, you might find that the extra expense is justified.
Attenuators with Power Amps
Reactive vs. resistive systems aren't the only considerations to make when it comes to choosing the best attenuator for you. Some of the more complex systems feature their own built-in power amp, which works similarly to a reamp box in real-time.
In the video above, Andy looks at the Bad Cat Unleash, which is one such device that not only attenuates, but can also make any amp louder with its onboard class D amplifier. Other devices, like the Fryette Power Station, work similarly but are even more advanced—in this case, featuring an actual tube power amp.
Attenuators with Crossover Cab/Mic Simulation
Beyond attenuators with built-in power amps, you can find even more feature-rich systems that offer features like cab and microphone simulation. The Universal Audio OX Amp Top Box is the example Andy demos in the video above, featuring a simple reactive attenuator along with built-in plugins and various cab and mic combinations. With the OX, you can even skip the cabinet and play direct or with some headphones plugged in.
The Boss Waza Tube Expander is another robust example of this kind of load box, featuring a built-in power amp, onboard DSP effects, an effects loops, and various controls over the reactive load with resonance and presence controls. Players can dial in their desired settings and save any combinations they like into 10 available rigs.