Matchless DC-30

Matchless DC-30

Matchless DC-30
Photo courtesy of Matchless.
Preamp Tubes: One EF86, three 12AX7s (one for PI)
Output Tubes: Four EL84s in class A, cathode-bias.
Rectifier: GZ34
Controls: Channel 1 – Volume, Bass, Treble: Channel 2 – Volume, Tone: Shared – Cut, Master
Speakers: one Celestion G12M Greenback, one Celestion G12H-30 (modified)
Output: 30 watts RMS

While one-man operations like Dumble and Trainwreck might have kicked off the “boutique amp” phenomenon, Matchless was arguably the first well-established “production boutique” company to succeed at selling significant numbers of point-to-point amps in the post-printed-circuitboard (PCB) era.

Matchless was founded in 1989 by Mark Sampson and Rick Perrotta, and the company’s flagship model was designed soon after, following Perrotta’s desire to “build an AC30 that wouldn’t break,” according to Sampson. As it turns out, the resultant DC-30 is far more than a Vox copy, though it does stem from the Matchless founders’ love of shimmering, saturated British class A tone. And it shares many AC30 touch-points such as a four-EL84 output section in cathode-bias with no negative feedback, GZ34 tube rectification, and other details we’ll examine. Internally, however, it looks nothing at all like a vintage AC30 – and that’s probably one of its top selling points.

As great as vintage Vox AC30s in good condition can sound, they are difficult amps to service, thanks to a complex internal layout. And they can be prone to breakdown on the road. Sampson and Perrotta sought to build an amp that was both roadworthy and sounded outstanding. As the chief designer, Sampson found himself naturally led toward a genuine hand-wired, point-to-point design, and Matchless amps are the epitome of this topology. Many players and marketing departments alike often refer to any hand-wired tube amp as being “point-to-point,” but strictly speaking the term doesn’t apply to amps built with circuit cards or turret boards, such as vintage Fenders, Marshalls, Voxes and others, even though every solder joint and wiring connection is completed by hand. Genuine point-to-point circuitry involves connecting each point in the signal chain and power stage with the components themselves – which is to say capacitors and resistors are usually soldered directly between tube socket contacts, pots and input jacks, and so forth – and that’s exactly how Sampson did it with Matchless, and how the current company still does it.

Accordingly, preamp tubes are mounted close to the inputs and Volume and Tone potentiometers in the front panel, and the internal components within the chassis flow logically toward the output, almost as if the circuit was rendered literally from a schematic diagram. This style of building is very labor-intensive and doesn’t suit every amp maker. But it certainly eliminates excess wire runs within the chassis, generally provides a very robust circuit, and sometimes makes component failure easier to diagnose and correct.

The DC-30 and its brethren TC-30 (2×10″ combo), SC30 (1×12″) and HC-30 head are two-channel amps of the old school, which is to say the channels are not footswitchable, but independent (though many players switch between them or use them in parallel with an A/B/Y pedal). The first channel effectively gives a Vox Top-Boost-style sound, with one 12AX7 for the first gain stage (with its two triodes wired in parallel for a higher signal-to-noise ratio) and another 12AX7 for the cathode-follower tone stack feeding a Bass and Treble control; the second channel is a modified AC15/early AC30 preamp using a high-gain EF86 (6267) pentode preamp, with a six-position “varitone” style Tone switch that routes the signal through different coupling caps to re-voice the channel as desired. The channels share a Cut control and Master Volume; the former reduces highs at the output stage, while the latter provides a much more tone-friendly volume reduction than many such controls used in the 1970s and ’80s – reducing the level after the phase inverter rather than just after the preamps – and can be rendered invisible when fully clockwise.

As used in the DC-30 – and the Vox AC15 (and briefly, the early AC30) that inspired it – an EF86 pentode preamp tube helps to create a sound in the amp’s second channel that is really quite different from the classic Top Boost chime and shimmer most consider the “classic Vox sound.” This tube yields a thick, rich tone with a full and relatively even reproduction of the frequency spectrum (as relates to the electric guitar), without the midrange grit or occasionally harsh highs heard in a 12AX7 used in a high-gain preamp stage. The word probably used most to describe it is “fat,” but it is also very firm and well-defined, and while it has a lot more gain than a 12AX7, it also carries a lot of body along with it. In the DC-30 the EF86 is used in an extremely simple preamp circuit, with a signal path that runs straight from the tube’s output to the Volume control via a single coupling capacitor, whichever of six is selected via the rotary Tone switch. The first channel provides tones that are far more familiar, but equally useful, best summed up as “sparkle with bite” at lower volume settings and “harmonically saturated grind” when cranked up. Between them, they offer an extremely versatile package.

Other aspects of Matchless’ design and construction are equally impressive. They gave the combo a rugged, punchy cab with a mixed pair of Celestion 12″ speakers – a G12M Greenback and a modified G12H-30 – for a broad, complex sound stage; a speaker-phase-reverse switch to ease pairing the DC-30 with another amp; a useful half-power switch, and top-notch touches like shock-mounted tube sockets and star-grounding for low noise.

These points and other little touches, such as one-watt carbon-comp resistors throughout the circuit, rather than the half-watt resistors found in most boutique amps, show to what extent Matchless set out to build the best amp it could possibly build. The DC-30 really is a modern classic on so many levels, and its continued use by a multitude of pros is further testament to the achievements of Sampson and Perrotta.

In 1999, Matchless closed its doors for a time after being hit hard by the crash of the Yen and a confluence of other circumstances, at which point Perrotta and Sampson moved on to work for Bad Cat. About a year later, the Matchless company fired up again, with Phil Jamison – the company’s production manager since 1991 – at the helm, and today he continues to run the company. The cornerstone models are still made by Matchless in Los Angeles, to the same specs and rigorous quality control they were when their designer was still with the company. Sampson has since designed amps for Sonic Machine Factory, and currently offers his own Star Amplifiers line.

This article originally appeared in VG May 2007 issue. All copyrights are by the author and Vintage Guitar magazine. Unauthorized replication or use is strictly prohibited.

No posts to display