If there ever was an argument for valves in audio, it no more evident than at home. A large, heavy, and hot valve power amp is an item of luxury. But if you ain’t got the home, or you just prefer to augment your collection with a good headphone set up, your source (surprisingly, even an iPod) and a good valve headphone amp are a match made in heaven. Why? Valves aren’t about performance – they are about sound. Woo Audio has been churning out quality amp after quality amp, each with one thing in common: milky smooth valves and a lot of power. Their WA3 is a great valve amp at a very good price point which puts the fuzzy wuzzies into your best records.
Build and Package
There is nothing to regret in Woo Audio’s construction. The WA3 is as sturdy as my stainless steel Marinoni Fango CX – nothing can conquer it. Woo has smoothed edgy corners, given the amp 4X4 clearance, and stopped the WA3’s bolts like a freaking nuclear damn. Each valve comes snuggly fitted into slim cardboard boxes, or dressed in foam sleeves, and the entire amp is tailor-fit into a brick of pressure Styrofoam. The WA3 is ready for nuclear holocaust.
It is solid, heavy, and bombproof. Nothing flexes. Nothing bends. The main case is battened down in extruded aluminium and ported for the valve and the power integrated power supplies. It's tubby backside secures the amp on any surface against the constant swapping of headphones. Rest easy, the WA3 won't slip.
Heat radiates up and out, through its open grill, but the amp vents through the bottom; and a modicum of exhaust escapes through the valve ports. Valves get warm, so exposing them on the top is important. The only reservation I have regarding this design is that there is no protective chassis for the valve tubes - not that anyone will lay things on top of the peaky WA3, but it never hurts to add a roll-cage.
The WA3’s belly button, the overly large and perfectly balanced volume-pot dominates the front panel. Ergonomically speaking, it is perfect: on the left is the 6,3mm headphone jack and on the right, the power switch. The back sports the Pre-amp out and one set of line inputs. Everything is firmly bolted and battened.
If I was a car guy, I’d say it is like a perfectly built AMG. But, I’m not, so I’ll just say that its industrial lines remind me of the best-engineered classic bicycles. If ever something was to go amiss, it could easily be replaced. Under the bonnet, Woo Audio use point to point wiring rather than circuit boards, a bragging point among audio makers, but for end users, a sign that do-it-yourself tweaking/repairing is simple.
One of the special features of a good valve amp is that its stock valves can be rolled. If you prefer more power, or longer valve life; even if you’d rather a different glow, you can roll out the old and in a new set of valves. The WA3 utilises 6922 and 6080 socketed valves from GE and Phillips. The combination sounds good, but valves will eventually burn out, needing replacements. Fortunately, it is as easy as mildly ‘rolling’ the valves around till they lift loose.
Valves have their own sound. Generally, they are known for being ‘warm’, technically, this warmth comes form high orders of harmonic distortion and a goodly amount of channel bleed. Distortion may be a bad word to newbie audiophiles, but it is actually widely used among high-end audio companies and among engineers. The WA3 harnesses this distortion to very pleasing results.
But before we get onto sound, I’d like to mention why this amp is a good value. 475$ isn’t cheap, but then, the WA3 isn’t a factory-churned amp. It is a beautifully engineered piece of kit. It looks great on top of a desk, a bedside stand, or near another audio component. The WA3 also has a serviceable pre-amp on the back. But more than anything, it supplies all the power you will need for the most intimidating of headphones.
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