MusicRadar

The baskey-weave grille with gold piping gives the tweaker a classy look well beyond its price tag.

1 of 4 » View in gallery

• Review

Bruce Egnater may not be that well known in the UK, but his reputation as one of the world's top amplifier designers is assured. With a stellar career spanning 35 years, Bruce's customers have included some of the biggest names in rock and metal.

These include Dimebag Darrell, Nuno Bettencourt and Steve Vai, as well as consultancies with Rocktron and Randall (who license Bruce's modular concept).

Based in Berkeley, Michigan, Egnater has always run his own custom shop, but is presently focused on a groundbreaking series of Chinese-built amps that have taken most of the world by storm in the past couple of years. Recently we looked at the Rebel 30 combo, but now it's the turn of the small but perfectly formed Tweaker.

"The build quality eclipses almost every off-shore amp we've seen."

Many so-called 'micro-amps' use simple metal box cases, mainly because they're easy to put together. By comparison the Tweaker is a conventional head, just smaller than average, with a neatly built and finished ply cabinet that's been covered in a thick-grained vinyl.

The head's front and that of the matching speaker cabinet is covered in a tough basket-weave grille and edged with gold piping, with vented rear grilles on both boxes to protect the valves and speakers. There's another grille on top of the Tweaker's cabinet, which is large enough to access the power valves once it's removed - a nice touch.

The amp chassis is a solid steel box with spot-welded corners and more ventilation slots. It's thicker than some US-made amps and needs to be, as it supports two substantial transformers.

The Tweaker's electronics are neatly arranged on two high quality printed circuit boards, one for the preamp and one for the power stage. These hold all the valve bases as well as the front and rear panel components.

Despite the PCBs, there's still a fair amount of wiring, which is all carefully routed and tied together. The layout is neat and tidy and the components are of a very high standard.

Operationally, the Tweaker appears at first glance to be a simple one-channel design, with controls for gain, three-band EQ and master volume. However, the five small switches on the front panel hold the keys to a vastly expanded tonal palette.

"Our product development method is basically by group decision," explains Egnater. "Often, final product designs barely resemble the original concept. The Tweaker is one of those products. My original idea was to have little plug-in modules - called Tweakards - that would change the tone, gain, EQ and so on.

"This was a fun idea, but not very practical. Because I think like a guitar-playing engineer, I have a tendency to overcomplicate things. One of our design team asked if we could just put those Tweakard functions on toggle switches. This was an obvious, ingenious idea so we did it.

"Each switch does something at a different stage in the circuit," he continues. "Tight and bright are at the beginning of the preamp stage. The tight switch cuts some of the deep bass out at the beginning of the preamp. The clean/hot switch simply widens the range of the gain circuit.

"The vintage/modern switch is in the power amp. In vintage mode the power amp is basically flat - not in a bad way - while the modern setting bumps up the low and high-end for a little fuller, clearer tone.

"The magical USA/AC/Brit switch changes the tone control components to closely mimic the EQ response of three different classic amps."

Around the back, the Tweaker has a pair of sockets for its series effects loop and two more for loudspeaker cabinets, along with an impedance changer and switchable mains voltage. The overall impression is one of tough, robust reliability combined with style and attention to detail that's way above what you might expect in this price bracket.