Altec 604-8G [Template]

Selling last remaining personal audio items.  Please see other listings for more interesting field coil drivers.
Rare
opportunity to acquire a matching pair of Altec 604-8G that have many
upgrades to make a studio standard from the past usable to a high end
user that wants the attack and dynamics that this speaker is capable of
combined with modifications that smooth out the response and give
greater musicality to the audio presentation. 

Both the low frequency and high frequency have been
converted to field coil instead of magnets. They are easily powered with
a 12-18 volt DC power supply at around 2 amps.  The stock cell horn has
been replaced by a round poplar wood horn with a 875 cycle cutoff with
the calculations done by Dr Bruce Edgar as a tractrix curve.  This
allows the operation of this speaker using any 16 ohm crossover designed
by Altec to drive a 604 speaker.  The last change was to biflex cones
carefully lifted from later Altec 620 speakers.  This cone gives greater
presence to vocals and piano in the critical 800 to 1500 frequency
band.  The diaphragms are Radian 1228-16 aluminum at 16 ohm.  The Radian
diaphragms use a special aluminum formulation in the dome which has
better sound transfer and dynamics than the stock Altec diaphragms. 
They also have better consistency unit to unit which allows for a more
accurate stereo image.







The condition and cosmetics have been listed as very
good.  However, the cones have had additional treatment to improve
performance so may be less in appearance depending on individual
judgement.  A small tear in the outer edge of one speaker has been
repaired and in no way effects the overall performance.  The
modifications were done by Sam Saye who has consulted on many notable
speakers that use field coil design. This pair was completed in 2005 to
verify the improvements possible by using a field coil over a
conventional alnico magnet.

Offered as a pair less cabinets and crossovers for $2800 obo.
Bidders
from outside the US are welcome but please contact first to discuss
shipping and payment parameters.  Again, please see other listings for
more interesting field coil drivers.