If you are reading this blog, you have an
affinity for speakers and tone that surpasses that of the casual
guitarist. You have no doubt encountered
the term "doping" when researching speakers. Some believe that doping creates monster speakers the way it creates monster Baseball all-stars. This is one of those oft misunderstood areas which can approach smoke
& mirror status. So, let’s carefully
enter the murky waters of speaker doping.
Put on your hip waders and READ ON!
Right off the bat, let’s dispel some common myths and
misunderstandings. First, speaker doping
refers to a treatment of the edge of the speaker cone. Some folks sell a snake-oil concoction to be
administered to the entire speaker cone in an attempt to "age" or "break-in"
the speaker. That’s a bunch of bunk, and
it is not what we are talking about here!
Second, in the question of whether to dope or not, there is no clear
winner. It’s not a case of one being
better or worse, just what is most appropriate for a given speaker design, its
application, and the desired result (tone).
Okay, so moving on. You all know by not that I love the HISTORY
involved in loudspeaker design and manufacture, so let’s start there. Very early in speaker design the paper cone
emerged as being the best way to reproduce sound that had been transmitted as
electric energy - a fact that remains unchanged to this day. The big game-changer in the world of speaker
design was, of course, the electric guitar.
The electric guitar changed everything in the world of
audio-electronics. Even in the 1940’s
& 50’s guitar players then, as now, liked to "turn it to 11". As players pushed their amps, often the
speakers were the first casualty. A
number of fixes were tried. Bigger
this, better that.
It was noticed that speakers often failed first
around the outer edges, where the movements were large, and met with the (nonmoving)
frame of the speaker. Here is a speaker
from an old Fender Concert showing typical fatigue cracking around the outer
edge (surround) of the cone.
One solution to this problem is applying a
rubber-like substance (dope) to the speaker surround. This application not only helps protect
against premature fatigue cracks, it also affects the tone of the speaker. In a nutshell, the application of "dope" to a
speaker surround results in:
A less raw, more controlled sound
A speaker that can hold its own better at higher
Reduction in "cone-cry" and "ghost notes"
brought on by large cone movements
A less articulate, less touch sensitive speaker
The more dope, the more these factors come into
Overall, a non-doped cone will sound more raw
and vintage; and a heavily doped cone will sound more modern and
controlled. So, it would be easy to say
that if you want a high-power monster for ... say, metal, you would want a
speaker with heavy dope, and for a low-volume articulate speaker you would want
no dope at all. In big, broad terms this
is mostly true. However, this must not
be considered a concrete law, as all of the other design elements of the
speaker also come into play heavily in determining the final sound of a
speaker. Furthermore, some cone designs
just plain sound better with dope, and some without. Oh, and all dope ain’t the
same, WGS for instance uses a special proprietary potion.
So there ya go, now ya know the rules of doping ... so go out and break them at your own discretion (we guitar players love to
break the rules)! Over the coming weeks
and months we’ll dissect other speaker components and dispel more myths. Ya all are the greatest, can’t wait till next