SPEAKERS, EARLY STEREO JUKEBOXES
The two most important things about jukebox restoration are
looks and sound. A "Grade 1" appearance restoration will come up
short if it doesn't sound as good as it looks. Sound system repair is no place
to cut corners. Re-coning of speakers if necessary is a good investment, older
speakers can rattle or sound mushy if the cones have deteriorated. This
generally shows up more in heavy bass notes.
Bad or incorrect tubes are another source of distortion.
It is a complete and total waste of time to plug new tubes into an old amp that
hasn't been repaired. New tubes can be ruined in a matter of minutes if circuit
or transformer trouble is present.
Decent tubes are beginning to get scarce. Distributors
are relabeling lower priced and unsalable
tubes with higher priced numbers and the average person doesn't know the
difference until the problems they are having get worse with a change of tubes.
I get several calls a year from collectors who settle on
one model of jukebox and end up with two or more of them. The calls usually go
something Re this: "Bill, I have three Seeburg
222 jukes and they all sound different. How can I get them to sound exactly alike?"
The short answer is: you can't! Why, you ask? It is next
to impossible to get 2 amps to sound exactly alike. Manufacturing tolerances
alone will cause sound variations. Add 30 or 40 years to the mix, and the fact
that three different people may have worked on the amps, and you begin to see
Different brands of tubes, even though they are the same
number, will not sound the same. The brand, quality and construction of
capacitors will cause variations in sound. But the biggest difference is the
output transformer. The transformers were wound on lathes by human beings. All
it takes to cause one to sound differently is a few more or less windings the
specs called for. Also, if the person overlaps a few turns, lets the metal core
touch windings, etc. there will be a significant change in sound.
I personally can't remember hearing two amps that sounded
exactly alike. However, I have found that for pure power, bass response, and
clarity of music reproduction, the Seeburg R is the
king of the hill, followed closely behind by the V and VLs.
I suspect that a lot of this has to do with the placement
of speakers and the size of the cabinet. Some jukes have great amps, but the
arrangement and type of speakers kills any chance they have of really knocking
your head off with sound.
Most, if not all, AMI jukes have one or two bass speakers
either down low in front, or in the middle of the grill. The bass speaker is
tied to both channels, which means that there is no stereo signal available.
The two side speakers are the only source of separation of the sound. They do
sound great because twice the power is being applied to the bass signal, but
very little is left for the side speakers, hence there is really not much
stereo effect. You have to stand directly in front of the juke to tell that
Early Rockola stereo jukes
really weren't because both channels were fed into one 12" speaker. To get
stereo, you have to ran remote speakers off the
terminal strip on the amp. Most people don't have the remote speakers, or even
enough room to mount them.
Early Wurlitzer stereo jukes had two different channels,
but one 12" speaker was really a midrange, and the other was for bass.
Yes, there was separation of the channels, but each was intended to respond to
a different frequency response. If you sit directly in front, down low, you can
Seeburg's early stereo jukes
were true stereo. But the down side was that their first amps were unbelievably
complicated! They took the "British" route and over-engineered the
system. They can really be tough to get right, however when they are, they
All early jukebox stereo amps were slightly down on
power. Most mono amps were rated at 25 watts, but could easily put out 55 watts
when pushed. The early stereo amps used 6973 tubes in the output, and the best
you can possibly hope for on a good day is about 15 watts per channel. Okay,
they were rated higher, but the power just wasn't there. So, the result is that
an earlier mono amp will outpace the stereo amps by a mile.
And the problem got worse when they switched over to
solid-state amps. Almost everyone was using germanium transistors in the output
stages, and they just didn't get the job done. They were rated at 25 watts per
channel, but 10 is closer to the truth. AMI amps used
early versions of silicon transistors, which helped, but the power still wasn't
there. After all, solid state technology was fairly new at the time.
Add 30 years to this mix, and you begin to understand why
some of the mid-60s boxes sound so bad. Manufacturers didn't stand still too
long, and soon amp design did catch up. By the late 60s, Seeburg
and AMI were out front in sound. It took another few years for Wurlitzer and Rockola to catch up. Actually, Wurlitzer didn't redesign
their amps until two years before they shut down. I suspect that they just
didn't have the funds for major changes. They had been losing money for years,
and the company was drained.
Should you avoid buying an early stereo juke? Probably
not, since many of the advances in components can be retrofitted into the early
amps, which will make a noticeable difference in sound quality. Also, these
same boxes are still real bargains today. In a couple of years this may not be
the case. This is a very good time to look to the future and buy another box
even if you don't need it today. If nothing else, it will be good trading material
in the future.
From James Loflin of Music and
Games Service comes a tech tip: "One way to get fairly decent sound from a
Wurlitzer using a cobra cartridge is to use a 2 mil needle on 45 records. The needle will ride higher in the groove and
eliminate the distortion normally associated with playing a modern stereo
record on an early system. The bass will be noticeably stronger, and the
If anyone else has a tech tip or just a bit of advice
that they would like to share with the readers, please send it to me by e-mail
or letter and I'll be glad to share it in the upcoming months. Also, any
questions that arise will be answered in upcoming columns.