The harmonica is an acoustic instrument, amplification has come from adapting equipment meant for other purposes. For example, the classic harmonica combination is a circa 1950s bullet style radio mic, like an Astatic or Shure Green Bullet, and a low power guitar amp, such as Fender Champ. While this Chicago style amplified sound suits many players, others want a cleaner sound, like the acoustic harmonica, only louder
Others, myself included, want both. To achieve this, the right mic is needed.
The classic bullet style mics, while sounding great through the right amplifier, sound very ordinary when plugged directly into a PA. Not surprising, given their distinctly Lo Fi mid 20th century design. A standard vocal mic, such as a Shure SM58, sounds far better through a PA. However these mics don't fit as nicely into the hands as the bullet mics do. Also, they often sound lame when plugged into a harmonica friendly amp.
What to do then? Some players have both mics on hand. Another approach is a vocal style mic, built specifically for harmonica. Like the Audix Fireball V.
This mic is readily available online, retailing for well under $150. It fits nicely into the hands, without the long body of a standard SM 58 type vocal mic. It has a rotary style volume knob, easily operated by the thumb. Very handy indeed.
The clean Audix Fireball V sound is just that, without the distinctive "honk" of a Shure SM 58. Plugged directly into a mixing desk with a standard mic cable, it works very well. I've had mine for over five years, and have never had feedback issues. It seems indestructible.
As the name suggests, the Audix Fireball V is a distinct red colour. Not that anyone can see this while cupped in the hands...
A useful volume control tactic is to set it to the mid point, then draw a line with a thin black marker pen, in line with the Audix logo. Set your mic to this level during sound check. Then when the band gets louder, you can dial in more volume for yourself.
So far so good. Now to plug the mic into other gear, an effects pedal (e.g. for delay), or an amp. The standard approach is a cable with a cannon type connector on one end and a guitar type plug on the other. I used these cables for 25 years, they have a basic problem. Impedance matching.
Omitting the technical details, a "low impedance" mic like an Audix Fireball provides a relatively weak signal into an effects pedal or amp, compared to a bullet style mic. The solution is an "impedance convertor", an attachment which fits on to the end of a mic cable, and, like the name suggests, converts the mic impedance into one which better suits the effect pedal or amp.
The result is a dramatic improvement in sound, as a mic like the Audix Fireball V will now drive an amp in a similar way to a bullet style mic, albeit with not quite the same sound. I wish I gotten on to this 25 years earlier.
While impedance convertors greatly improve the sound through an amp or effect pedal, they are cumbersome. An impedance convertor attached to an amp input is an accident waiting to happen. One careless knock and your amp could be damaged.
Unless of course you use the Audix T50k impedance convertor. This has a short cable separating the two ends, thus relieving the strain on the amp or effects pedal plug.
So. If you buy an Audix Fireball V mic, spend the extra $25 on the Audix T50k impedance converter. RockinRonsMusic has them both.
Then go out and play loud.
Tony Eyers
www.TonyEyers.com