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Guitar Technology

Gear Reviews, Tips and Techniques By Dave Lockwood
Published February 2006

Guitar Technology

Fliptone v.25

Instrument amp with flat-panel speaker

The revolutionary flat-panel loudspeaker technology developed by British company NXT has taken a while to filter down into instrument amplifiers, but it's here now in the form of the Fliptone v.25 from Traveler Guitar. Looking like a chunky laptop computer, the Fliptone incorporates a two-channel preamp with mic and line connections, EQ and on-board effects, plus a power amplifier driving a 12.5 x 8.5-inch flat panel speaker that hinges up from the casing for operation. The system is powered by an integral 12V battery — effectively a lead-acid gel-based car battery — but can be run from its charger whenever mains power is available. Using a lead-acid battery, of course, means that the Fliptone has no issue with the number of recharge cycles and no 'memory effect' (there's no need to discharge it completely before recharging). The only thing you need to avoid is leaving it discharged for extended periods.

In theory, the flat-panel speaker offers a flat frequency response, albeit with limited low-frequency extension, and a bi-directional radiation pattern, characteristics that should make it well suited to amplifying acoustic instruments where a natural sound and good dispersion, rather than high levels and projection, are the goal.

The Fliptone is manufactered by the Traveler Guitar company, who make compact guitars that will fit in a suitcase or that can be easily transported as hand luggage. One of the applications for the Fliptone is clearly therefore that of 'hotel room amplifier'; a role it performs admirably when partnered with a Line 6 Pod or similar modelling processor with half-decent speaker modelling. A pair of RCA phonos (summed to mono, of course) make it easy to connect a portable CD player or iPod to play along with.

Out in the live performance world it fares a little less well, with its limited headroom and lack of bottom end restricting its practical applications. However, you could certainly use it for subtly amplifying a 'lead' acoustic instrument within an otherwise all-acoustic ensemble, and it seems eminently suited to, say, classical guitar in the corner of a restaurant, where you might want any amplification to be particularly discreet. To my ears, on all sources the Fliptone sounded much better with a little mid-frequency cut, so perhaps that could have been built into the response of the system. There is the option of connecting an extension speaker, for more level and bass, but surely that's rather defeating the object? Used within its limitations the Fliptone offers a uniquely effective solution to the challenge of providing amplification without bulk or weight. It costs £499 in the UK. Dave Lockwood

SUMMARY: Where size and weight are the primary issue, nothing can match the Fliptone. Just don't expect it to go very loud or produce any real bass.

Big Bends Nut Sauce

Guitar nut and saddle lubricant

Guitar TechnologyGuitar players have employed many different substances to reduce friction between strings and bearing surfaces, especially in vibrato-equipped instruments, ranging from pencil lead shavings to silicone grease — my own favourite has always been a DIY concoction of pure graphite powder mixed with a small amount of Vaseline to bind it together. Most of these improvised solutions work to some degree, but tend to be either messy, difficult to apply or not very durable.

Addressing all these issues, Nut Sauce is a non-toxic, non-corrosive dedicated guitar string lubricant that won't affect the finish of the instrument. It is also designed to stay in place, in the nut slots, under the string guides or on the bridge and saddles, at least until the next string change. Supplied with a convenient long, narrow applicator that allows you to apply just enough and no more, Nut Sauce really does work. Of course, it's not a substitute for a Floyd Rose, but it will give you greater tuning stability on traditional Strat trems (if used within their design limitations) and I've also used it to good effect on acoustics to stop strings creaking in the nut when using alternate tunings on stage. A little on the bearing points on non-trem guitars allegedly reduces string breakage and it's excellent for lubing the mechanism of a pedal steel — the applicator lets you get it into all the right places and the substance itself has just the right viscosity to stay there.

Two sizes are available: the 1.5cc 'Groove Luber' (£12.50, pictured here) and the 0.3cc 'Lil' Hummer' (£3.50). Dave Lockwood

SUMMARY: The best guitar lubricant I have used so far, both for effectiveness, longevity and ease of application.


Guitar TechnologyThe Swedish-made Ehrlund Acoustic Pickup for acoustic string instruments from guitar and violin up to double bass, claims to offer superior performance to other piezo-based contact mics. No technical details are available at present but the company suggest that the unconventional triangular shape of the transducer does have a bearing on its more microphone-like output. The Ehrlund pickup has a larger transducer area than most similar devices and is also significantly more tolerant of load impedance (most piezos need to see about 5MΩ to work properly). The pickup is simply stuck onto the source with the supplied tacky putty, but as with all soundboard transducers, positioning seems to be crucial. Samples have just arrived for testing, but you can download some intriguing MP3s from the manufacturer's web site:

Guitar TechnologyParker Guitars have unveiled their first acoustic guitar, the P8E. Its unconventional body shape (we'd expect nothing less from the creators of the Fly) is likely to divide opinion, but there's no doubt that this is a rather interesting instrument. Constructed from premium materials, it has a solid cedar top and flame maple back, laminated flame maple sides, a mahogany neck, ebony fingerboard and bridge and bone nut and saddle. Fishman provide the electronics — a hum-cancelling magnetic pickup in the neck position and an under-saddle piezo transducer — and the guitar has XLR and jack outputs. The PE8, which is also available in black, is to be officially launched at the Winter NAMM show in January 2006, though details of UK pricing and availability had not been announced when we went to press.

Sound Technology +44 (0)1462 480000.


Miking your Pod?

Most people who buy a modelling guitar preamp, such as the Line 6 Pod, do so because it gives them the ability to record without microphones. However, if you're after a more authentic sound, a combination of microphone and DI can yield interesting results, especially if you have a good-sounding space you can use. Many of the classic guitar tones were created using a combination of a close mic and a mic further back in the room, and whilst modelling preamps do a good job at recreating the close-miked sound, it's the way sound interacts with the room that often creates the real magic.

You can replicate this by DI'ing one of the outputs from your preamp into your recording system, whilst using the other to feed a powered full-range monitor which you then mic up. Place the mic around six feet from the speaker and then fine-tune the mic distance and position by checking the results over your studio monitors. You don't need to have the monitor running at ear-splitting levels, though it should be loud enough to hide any ambient noise.

Guitar Technology

Combine the miked and DI'd signals in mono and adjust their balance until they are approximately equal so you can hear the effects of any phase cancellation and check that the sound is mono-compatible. The miked version will generally sound warmer and more complex than the DI'd sound, but the overall effect will change as you vary the mic's distance and height. Different mics will give different results, just as when miking a real amp.

Miking up the signal from a guitar processor might seem like an unnecessary complication, but a little experimentation should convince you that there are a lot more tonal variations to be had this way than by just DI'ing. Paul White

Vox AC30 Custom Classic

Class-A valve amp combines the best of new and old

This latest take on the iconic AC30 seeks to remain true to the sound and feel of the 1960s originals whilst bringing the amp up to date by adding features that today's players want — master volume, reverb, an effects loop and a few more unexpected features to boot.

The AC30 Custom Classic is built in China and, unlike the point-to-point-wired originals, employs PCB-based circuitry. The review model, the top-of-the-range AC30CC2X combo, with two 12-inch Celestion Alnico Blue speakers, is priced at £1049, but cheaper options are available in the form of the AC30CC2 (£699, two Wharfdale speakers), the AC30CC1 (£659, one Celestion Neo-dog speaker), and the AC30CCH head (£499).

Guitar Technology

All models feature the same amp, an all-valve Class-A affair, using three 12AX7 preamp valves, four EL84 output valves and a GZ34 rectifier. There are two channels — Normal, equipped only with a volume control and a 'Brilliance' mini-switch, and Top Boost, with volume, treble and bass knobs. The Top Boost channel's EQ can be switched between Custom mode, modelled on the recent AC30 Hand-wired's EQ, and Standard mode, which covers a much wider range. A mini-switch allows you to blend the two channels together, mimicking the old trick of using a Y-lead to play through both.

The Normal channel has plenty of clean headroom reaching into some pleasing crunch when pushed flat out, and the Brilliance switch adds some desirable sparkle to what is quite a flat basic sound. The Top Boost channel, on the other hand, is very bright, with equal measures of growl and shimmer once you start to drive it. Link the two together and as you add Normal gain to the Top Boost channel, you'll notice the sound gradually thicken and then increase in drive and distortion in a very controllable and musical way. Like all tube amps, this one performs better with the master volume well up, but it doesn't strangle the sound too badly at lower levels. Things can get a little shrill when using guitars with single-coil pickups, purely because there's so much top end on tap, but a high-cut control just before the master volume allows you to tame this to just the right extent. The vintage-style tremolo circuit and long-tank spring reverb both work well.

The amp can be run at 22W, giving a warmer sound at lower volumes and prolonged tube life, or 33W for more clean headroom and overall level. You can also switch the PSU capacitors for a looser or tighter response. The effect of both is subtle, but if you're an a fan of the AC30 sound you'll welcome the ability to tailor it even further.

But while the sound of the AC30CC is thoroughly convincing, and every one of the new features which have been added is very welcome, a few concerns remain. Accessing the valves requires pulling out the whole amp chassis, which in turn involves disconnecting the reverb tank and un-soldering the wires connecting the speakers! This is something many potential users won't feel comfortable doing themselves (Vox customer support even advise against it), but what if a valve fails in a gig situation? Even if altering the chassis design was just not possible, surely the speakers could at least connect via a jack?

There was some rattling from the handles and back panels when used at high levels; nothing that tightening a few screws can't fix, but it is a small reminder that this is a mass-produced amp. The mini-switches on the control panel don't really seem sturdy enough, and indeed, the Input Link switch in the review model is already misbehaving. Vox should of course be commended for producing such an affordable AC30 that really delivers the goods, but this is perhaps one cost-saving too far. This amp has AC30 character in spades and while it couldn't be considered versatile by modern standards, it covers more bases than you might expect. From clean country and jazz to overdriven blues and rock, it's difficult to get a bad sound out of it. David Greeves

SUMMARY: A fantastic-sounding amp which lives up to its billing as "the most tonally flexible and affordable AC30 to date", but compromised by a few cut corners.