RE: [Harp-L] Performance setup - hearing and feedback

["Joel B. Chappell" <joel.b.chappell@xxxxxxxxxxxxxxx>]

Greetings from the old friendly electronic engineer again. There is a great
deal of wisdom and knowledge in the first two paragraphs that John Potts
wrote. If you can't hear yourself get a good floor monitor and keep the
house speakers down.

As memory prevails most bullet mics designed some 75 years ago were never
intended for musical/broadcast/entertainment application. Primarily they
were intended for public address/paging operations along with some use in
radio communications... thus they were intended for single mic applications
located a good distance from output speaker, thus feedback was just not a
problem. Their design is omni-directional as most hi-Z mics are, and they
have no anti-feedback qualities designed in. They are a very archaic design.
The only reason I can see in justifying their use on stage with a harp is
that they are easier to hold close to the harp than most modern
uni-directional mics. They also have some mystique due to their antique
radio 1930's appearance. They certainly are not music quality devices and
due to their omni-directional qualities are not feedback friendly, There are
thousands of mics on the market that are much more suitable for amplifying a
harp. I have been using mics and designing them into systems for over 60
years and "bullet mics" would be my last choice for any application. Bottom
line = you are far better off using a classic Sure SM57 with a mixer that
has some anti-feedback circuitry. Do not run a mic through a guitar amp and
be sure to observe the 3 by 1 rule in mic placement. Follow all the other
rules and practices that prevent a system from "boiling over" with
feedback...like keeping the house amps down.

Joel B. Chappell
Milford, NH 03055

John F. Potts wrote:

There is a well known harp player (I forget who) who has said that if  
you can hear yourself when you are comping you are playing too loud.  
When playing in an electric/amplified environment you've just got to  
accept that there will be occasions when hearing yourself may be a  
problem.  Often bands that play too loud get too loud because one of  
the musicians can't hear himself well enough, so he turns up, then  
another musician turns up, and so on, until the whole band is too  
damn loud.

I'm not a fan of bullet mics for a number of reasons, one of which is  
that many of the more popular commercially available bullets are  
feedback prone.  A fairly reliable method for controlling feedback in  
a live performance situation is to use a mic with a volume control,  
set the amp's volume at the "sweet spot" (which may be pretty high)  
and backing off the volume on the mic itself to set performance level  
volume.  This reduces the output gain so that the mic is not as hot  
and will usually control feedback while allowing the player to get  
good tone from the amp.

The tone of some mics will degrade if the mic volume is turned down,  
but many (like Greg Heumann's Ultimate series mics) sound just fine  
used this way.  Some amps are just too high gain for the method I  
have described to work well for controlling feedback, in which case  
the player needs to swap out preamp tubes.  If your mic doesn't have  
a VC another way to accomplish output signal gain reduction is to use  
an MXR 10 band EQ pedal which has gain and volume controls and use  
those to reduce how "hot" the output signal from the mic is.  Of  
course, you can also use the EQ freq sliders to notch out the freqs  
that are feeding back.  But the gain and volume sliders are actually  
more useful than the EQ adjustments.

Personally, I am not a fan of harp specific amps and I don't like  
what the Kinder AFB+ does to my tone.  But, depending on what kind of  
tone you are after, some bass amps can sound very decent for harp and  
are less feedback prone than many guitar amps.  But if you are after  
a "crunchy" or distorted Chicago type tone, a bass amp is not going  
to give you that.

Hope this helps.

JP