Probably best known for their unique tuck-and-roll amp covering that was offered in a variety
of sparkly colors, Kustom was one of the first amp
manufacturers to find success with solid-state
technology in the 1960s.
I have one of these really cool Kustom
amps (at least I think they’re cool),
and I’ve always been curious about
what the “100” on the front and “7”
on the back indicate. It seems that no
two Kustom amps are the same. Why
is this and what are these worth today?
Bill in Jacksonville, FL
Don’t let anyone tell you otherwise—
Kustom amps are way cool. Many players
think these amps sound great, and bands
such as Jefferson Airplane and Creedence
Clearwater Revival used them heavily in the
1970s. Kustom amps are important because
the company really pushed the envelope
with unique cosmetics and offered virtually
endless options. But more importantly,
Kustom, along with Acoustic and Standel,
were the first manufacturers to successfully
build and market solid-state amps when the
technology was new in the 1960s.
Bob Ross founded Kustom in Chanute,
Kansas, in 1965. His amps immediately
stood out because of their “tuck-and-roll”
covering made from a material called
Naugahyde, a vinyl-coated fabric that
feels like squishy plastic. And Kustom
offered this unusual covering with the
option of seven sparkly colors: black,
blue, cascade (blue/green), charcoal, gold,
silver, and red.
If you ever have a chance to see a vintage
Kustom catalog, you’ll instantly realize
why every Kustom amp appears to be different—
the company offered nearly every
possible configuration you could think of.
Endless options are great, but trying to differentiate
and identify Kustom amps can be
extremely frustrating because three different
sets of identification numbers were used:
series numbers, model numbers, and catalog
Series numbers are usually found on
the front of the amp—under or behind
the Kustom logo—and consist of values
like 25, 50, 100, 200, and higher.
Generally speaking, these numbers
indicate the amount of power multiplied
by two. For example, a 200 series
amp means 100 watts of power. Model
numbers are normally found on the
serial-number plate located on the back
of the amp, and they range from 1 to 8.
The model number indicates the chassis
used—with a higher number denoting
more features—and repairmen relied on
these numbers to know what chassis they
were working on. Lastly, the catalog numbers
were used in price lists and catalogs
so a customer could order the exact
amp he or she wanted.
These catalog numbers typically
followed a number/letter
format of X-XXL-X. The first
number indicated the number of speakers
[usually 1-4], the next two numbers
indicated the size of the speakers [10, 12,
15, etc.], while the lone letter represented
the brand of speaker [A for Altec Lansing,
C for CTS, J for Jensen, and L for JBL].
Finally, the last number in the sequence
indicated the aforementioned model number.
Still with me?
So, the “100” on the front of your
Kustom tells us it’s a 100 series amp and
has an approximate output of 50 watts.
The “7” on the back means it has a model
7 chassis, which includes reverb, vibrato,
and tremolo (the controls on the front also
confirm this). Unfortunately, since we don’t
have the catalog number (catalog numbers
only appeared in catalogs and not actually
on the amps), the only way to determine
what speakers your amp is equipped with is
to disassemble it.
Without knowing the
catalog number, the only way to determine this K
100’s speaker setup
is to remove the back panel.
As mentioned previously, these amps
used early solid-state technology and have
a reputation for being built like a tank.
But road wear and heavy use was typically
not kind to the soft, Naugahyde tuck-and-
roll covering, and many of the amps
that survived over the years are in rough
Cosmetic condition is the number-one
factor in determining the value of these
amps, and cover color follows as a close second.
Black seems to be the most common
color and the other six are slightly more
desirable, with gold and cascade probably
the most rare. These amps also need to be
in working condition, since it’s difficult to
find replacement components—especially
the germanium transistors. Today, your amp
is worth between $400 and $500 because
it still works, has the more desirable blue
covering, and the covering is in good condition.
If nothing else, it’s a treasure for the
Zachary R. Fjestad
is author of Blue Book of
, Blue Book
of Electric Guitars
, and Blue
Book of Guitar Amplifiers
For more information, visit
Zach at email@example.com