NAB Hubs Help Page
adaptors fit metal NAB 1/4" audio tape reels, and will work with
virtually any 10.5" reel-to-reel deck which has reel retainers built
into the reel table spindles.
Most consumer audio machines made after 1970 have these; the two common
spring-loaded (Sony, Akai, Roberts, Pioneer, Dokorder, Tandberg; see at right) and
screw-twist (Teac, Tascam, Fostex, Ampex; see below). You're likely already familiar with these if
you use your
machine in the vertical position with 7" reels; if not, its
owner's manual explains how they work. Otari is the exception; their proprietary design is not compatible with NAB adaptors other than their own. Our TC-503 NAB adaptors fit just one
Otari-labeled product family we know of; the Teac-manufactured MX-50
and its variants. Otari is still very much in business, and
their clamp type hub adaptors can be obtained thru servicing dealers.
Some older decks have NO integrated reel retainers, relying instead on
push or snap-on rubber caps to hold reels in place. These machines were
not designed for routine vertical use and cannot be used with most NAB
adaptors (including ours; more on this below).
is a typical (Teac) screw-twist spindle lock shown in the open position
(unscrewed fully CCW), ready to have a 7" reel (or our NAB hub adaptor)
inserted over it. Sping-loaded spindle locks look very similar when open (the upper and lower splines are aligned in the same manner), although the overall
spindle length is usually shorter and the upper splines sometimes extend to
the top of the spindle.
is the same spindle lock still in the open
position, but now with our hub adaptor inserted over it. For clarity, no tape
reel is shown; normally it would be placed on the reel table first, and
the hub then inserted over the spindle (and seated into the reel's center
hole). If shims are being used (see below), they insert between the reel tables and the reels.
C) Here is the spindle now in the closed or locked
position (screwed in fully CW), with our hub adaptor secured in place.
The spindle's upper and lower splines can clearly be seen to now be
unaligned; spring-loaded retainers are very similar in appearance when
shows a 10.5"reel loaded and locked in place; ready to play. The Teac
A-3300SX image below left shows the entire machine with
both reels mounted. Always doublecheck that screw-type retainers
are tight before initiating tape movement; a reel falling off while in
fast-wind becomes a dangerous projectile.
older 10.5" decks like the one at right lack reel retainers and
therefore cannot be used with our hub adaptors (note; the other
commonly available variety also does not work). Our product also does not enable mounting 10.5" reels on machines which were never intended to use them. Many consumer reel-to-reel decks accept only 7" or smaller reels. A simple
test: are your reel tables under 3" in diameter, or the reel table
spindles less than 10.5" apart? If yes, your machine cannot handle
10.5" reels; they physically will not fit. Second test: is the
distance between either reel spindle and the nearest corner of the head block
cover less than 5.5"? If yes, there is
insufficient room for 10.5" reels. One final clue: virtually all 10.5" machines have a tape size selector switch (usually marked large/small, 10/7,
or similarly) used to adjust fast-wind speed and torque. If your deck lacks this feature, it likely accepts 7" or smaller
reels only. Note that failing to set this switch properly can cause severe tape stretching and tape spillage or breakage when transitioning from fast forward or rewind to stop; don't ignore it!|
is a Teac A-3300SX with 10.5" reels mounted using our hubs. Note the
location of the reel tables way out overhanging the upper corners of the
front panel; this is typical of most 10.5" machines and is necessary to
provide clearance for the reels. The size selector switch is right next
to the speed selector, under the left reel. This switch adjusts fast
wind speed, torque and braking balance to match the different reel diameters.
is a Teac A-2300SX; this 7" model's reel tables are more centered,
making for a much shorter machine. The 7" reels barely
clear the head block; there simply is no room for larger reels.
Note also only two switches are present under the left reel
(compared to the A-3300SX's three); this deck does not need or have a tape size selector
NAB reels are quite a bit thinner than plastic ones, and sometimes
require spacer shims. These when placed between the reel table and reel, raise the reel height slightly so as to
properly align the tape path and prevent the tape rubbing against the edge of
the reel. On Tandbergs and older Akais as
well as some Revoxes and Studers, the spindle lock doesn't tighten up
enough to hold metal tape reels snugly against the reel table unless
shims are used.
This looseness can cause the reel to move and rattle against the hub when
fast-winding. Placing a shim between the reel table and the metal reel
increases the overall reel thickness, and dramatically improves the
force so that the reel will not shift within the hub adaptor. We do not
supply shims with our hubs or separately. Shown above is a pair of Otari-manufactured
rubber shims; virtually every reel machine maker had a version of
these, but only Tascam and Otari still sell them. Fortunately, you can
easily make your
own; see at right.||
discovered a great way to create shims by utilizing round paper or cork
disposable drink coasters. Party goods stores sell these, and so do
package stores (usually printed with beer logos). Bars and restaurants
use these and throw them away after one use; simply take yours home
with you. Coasters right around 1mm thick and 3.5" to 4" in diameter
work great. Find and mark the center point; then punch a hole with an
awl or icepick. Carefully enlarge the hole to about 15mm diameter using
a ream, scissors blade or other pointy implement until it just
down over your reel table spindle and flush against the reel table.
Neaten up the hole edge and you're done. The hole may fray and enlarge
with time if removed and remounted routinely (unneeded unless you
switch reel sizes a lot) but given that these are
virtually free and quick to make, this aging issue does not pose a
per pair plus shipping
Why choose our hub adaptors? Ours are exact copies of hubs Teac/Tascam
supplied with their decks; compare the Teac hub on the left to ours on
the right. Sony, Pioneer, Tandberg, Technics, Dok and and others
all supplied similar ones. Our TC-503s are practically indestructable.
The only other variety commonly available today (Tascam TZ-612) has
moving parts which rub and wear, and may fall
apart with age or if overtightened. And the BEST reason: ours are
less than half
the price and cost less to ship...
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