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Our pick of the month’s most delectable, wallet-bothering new gear
Q&A What is it?
It’s a new reactive load box from Boss that performs quite a few useful jobs, especially if you’re into recording valve amps. Its most basic function is a highquality attenuator. As such, you connect it up between your amp and speakers. Positioned there in the signal chain, it lets you run the amp flat out, so you get all the rich tone and chunky response of an amp running at full tilt – but the actual audible output from the speaker can be adjusted to any volume level you prefer, from a whisper to a roar.
The Tube Amp Expander also has a 100watt analogue power amp inside, meaning it performs another very handy function. If you have a small combo that you love the tone of, but is not powerful enough for gigging, the Tube Amp Expander can be connected to external cabinets and amplify the signal from your small amp to stage-ready volume levels without altering its juicy feel, tone or dynamics. In other words, you can transform your dinky fivewatt combo into a 100-watt 4x12 Goliath.
There are 22 mic’d cabinet emulations onboard, both close- and room-mic’d, so you can record authentic tones from your valve amp straight into a recording device, with no speakers involved, plug straight into a PA, or practise with headphones on but with the amp running in its sweet spot (for those times when you can’t make a racket but still want solid, authentic tone). You can choose between emulations of various classic mics and there is a suite of stereo effects, from reverb to compression and EQ, that you can add in along the way.
I’ve used reactive load boxes before – what’s so special about this one?
Boss states that the Tube Amp Expander’s analogue power amp and Boss’s proprietary Tube Logic circuitry are the big deal here. The company assures these provide smooth, finely adjustable attenuation without introducing any sonic ‘artefacts’ that degrade your tone. Some players who’ve used reactive load boxes in the past have felt they can, in certain scenarios, sound a bit artificial. Boss says this one doesn’t – though we’ll have to wait for a review model before we can judge the truth of that claim.
How is a reactive load box ‘better’ than an old-fashioned attenuator?
Traditional attenuators are essentially high-powered resistor networks. They provide a load that lets the amp run flat out while allowing you to reduce the amount of volume emanating from the speaker to your preferred level. But the interaction between an amp and a speaker when you’re playing is complex and dynamic. Old-fashioned attenuators can stifle that interaction, deadening the amp’s playing dynamics. Modern reactive load boxes, such as the Tube Amp Expander, are designed to mimic the natural interaction between your amp and a given type of speaker more faithfully, meaning the resulting tone and playing feel is truer to the character of your amp.
What does Waza mean, exactly?
‘Waza Craft’ is the Japanese term for anything made to the pinnacle of the maker’s ability. In everyday terms, this means Waza-labelled effects pedals and amps receive higher-spec components than their standard-production equivalents, and generally they come with
custom functions, which are not available further down the Boss range.
What else should I look at?
In terms of high-spec reactive load boxes, the one to beat at the moment is Universal Audio’s OX (£1,170). In our recent review of the OX, we said: “It has a sophisticated reactive load circuit that properly mimics a loudspeaker’s constantly changing characteristics, so the amp’s dynamics are preserved at any volume level… the OX’s speaker volume attenuator control has five different levels of loudness, plus an ‘off ’ setting. The OX also features built-in digital cabinet and microphone emulations, together with up to four simultaneous studio-quality effects, including plate reverb, delay, compression and EQ…”
The Tube Amp Expander has no steps in its attenuation, so you can adjust it as you would a standard volume control, plus you can fine-tune your amp’s response to the load box – in Boss’s words: “the Resonance-Z and Presence-Z panel controls optimise the all-important impedance interaction with your amp’s output transformer.”