This site is dedicated to the buying, selling and restoration of the Federal Signal TWINSONIC lightbar.
Did you watch EMERGENCY as a child... Ever saw a chase scene on CHiPs? Remember the Blues Brothers mall scene? If so.... Then you know the TWINSONIC
I, Ryan Shanower have been buying, selling and restoring Twinsonics for over 10 years now. I have about 200 lightbars in my coffers. I am going to try to make this website the most informative site on the net.
I am always looking to purchase more Twinsonics. If you have one or a hundred I am sure I have a home for them here!
I offer restoration, buying and selling of parts and how-to's for the avid collector. If I don't have it... Federal didnt make it in regards to the Twinsonic.In this site I will try to compile a complete list of pictures and information on every Twinsonic model there was. If you have any other news, tips and or items that should be listed here, please feel free to drop me a line!
The Federal Signal Twinsonic light bar is the brain child of Earl Gosswiller, (1912-2009) Lead design engineer
for Federal Signal.
His ideas were put into motion (see patent numbers 3,404,371 and 3,271,735 and 3,281,030) in 1967 for a fully
enclosed rotating beacon light that stretched across the roof of patrol cars. The Twinsonic was debuted at the
1968 International Association Fire Chiefs convention in Louisville Ky. The light bar was as instant success.
The light bar sold more units in 1969 then the model 11 Visibar's past 2 years combined. In 1968-69 there were 400 units built each year. The light bar was built by hand in an assembly line process. Once the light bar was conceived, Federal introduced the model ts24 (58 watt) speaker to be housed inside the stainless steel enclosure.
The model 12 series A1 and A3 was a 54" full size light bar with 2 tall triple reflection single direction mirrors
mounted next to the rotators. The first additions had black anodized aluminum frames and completely round
bulb holders.
The next brain storm from Earl was the model 12X which took the 2 tall triple reflection mirrors and cut them
horizontally and rotated the top half 180 degrees to face the rear. Now you had just as many flashes to the front as you did the rear.
The next product line was the 12F light bar which originally consisted of 4 par 36 (4414) bulbs mounted next to
the rotators and these flashed in a wig wag pattern to the front and rear. By 1972 this was replaced by the new
style 12F with lower front facing cascade mirrors and a top flasher housing with 2 polycarbonate filters made
from cut down dietz lenses.
Series A1 light bars featured metal speaker trays and both series 1 and series 2 motors. The series 1 motor has
rounded sides and a flat top and bottom. This motor is assembled with stronger windings to reduce fatigue over
time. The series 2 motor had similar properties as the heavy duty series 1 model but the castings were different.
The second series had an X in the cast on the rear of the housing.
In 1972 Federal Signal entered into an agreement to build a special service bar to meet California Vehicle Code
Section 25252 states that: "Every authorized emergency vehicle shall be equipped with at least one steady
burning red warning lamp visible from at least 1,000 feet to the front of the vehicle. This model of light bar was
the CTS series. This light bar featured a par 46 (ge 4001) steady burn red bulb on the inner driver’s side and a par 46 (ge 4478) mounted inner drivers side to the rear. This bulb was normally mounted in front of a cut out in the dome with an amber panel bolted and glued to the rear of the lens.
By 1974 they came out with a "small" line of Twinsonic light bars that measured 47 1/4 inches in length. These
were available in all the common models.
In 1974 they also came out with their Economy line which removed the stainless steel strips from the bar and
replaced the stainless speaker cover with an aluminum one.
In 1974 they introduced the A3 series line. This line featured natural color aluminum frames. They also switched
to plastic speaker trays and the "skinny" bulb holders for the rotators. (I have yet to see a series A2)
In 1976 we see a change to the new series 3 motor. This motor is round in diameter and was not built to meet the
same demands of the series 1 and 2. The series 3 motors were offered in the Twinsonic rebuild kits.
In 1977 Federal Signal introduced the "medium" line of Twinsonics which measured 47 1/2 inches. These
light bars were available in all the common Twinsonic models.
The years 1976-1980 saw the biggest production years of the Twinsonic. These bars lost production numbers
when the aerodynic and jetsonic light bars came into fruition. The last light bar according to Federal Signal was
sold to the Pierce manufacturing company in August of 1984. It was sold to a department in South Dakota.
Federal Signal manufactured 30 different variations of the Twinsonic.
Per a Federal Signal Price list from 1981:
The Twinsonic light and sound system set the standards for vehicle warning systems! It has two sealed beam rotating end lamps reflecting on inner mirrors, providing brilliant flashes of light warning. Models are available in single direction (front) or dual direction (front and rear). Choice of 12 or 24 volts.
------------------------------Twinsonic Light and sound system (full size 54")----------------------------------------------------
Model Description Original list price from 1981 1978
12 Twinsonic tall cascade mirrors facing front 12 volt. $446.00 $300.50
12 Any Twinsonic listed 24 volts applications add. $22.75
12Q Same as above but with halogen style outer bulbs. $455.25
12E Rotating outer lamps no inner mirrors or flashers. $334.00
12EF Rotating outer lamps with dual front and rear Par 36 flashers. $400.50 $344.25
12EV Rotating lamps with "V" mirrors. $371.25
12F Rotating lamps with front reflecting plus front and rear flashing. $511.25 $344.25
12FQ Same as above but with halogen style outer bulbs. $531.25
12X Rotating lamps with front and rear reflecting. $460.25 $310.00
12XQ Same as above but with halogen style outer bulbs. $489.75
CTS1 California style with front steady burn Par 46, rear amber flashing Par 46. $571.25 $370.75
---------------------------Twinsonic Light and sound system (Intermediate size 47-1/4")-------------------------------------
12M Twinsonic tall cascade mirrors facing front 12 volt. $440.50
12MQ Same as above but with halogen style outer bulbs. $469.25
12MF Rotating outer lamps with front reflecting and front and rear flashers. $506.26
12MFQ Same as above but with halogen style outer bulbs. $529.25
12MX Rotating lamps with front and rear reflecting. $456.00
12MXQ Same as above but with halogen style outer bulbs. $487.50
12MEF012 Rotating outer lamps with dual par 36 flashers front and rear, Aluminum grill $444.11
12MEV012 Rotating outer lamps with "V" mirrors and aluminum grill $324.38
CTS1M California style with front steady burn Par 46, rear amber flashing Par 46. $541.25
--------------------------Twinsonic Light and sound system (Compact size 43-1/2")--------------------------------------------
12S Twinsonic tall cascade mirrors facing front 12 volt. $437.75 $300.50
12S Any Twinsonic listed 24 volts applications add. $22.75
12SQ Same as above but with halogen style outer bulbs. $447.00
12SF Rotating outer lamps with front reflecting and front and rear flashers. $502.00 $344.25
12SFQ Same as above but with halogen style outer bulbs. $521.75
12SX Rotating lamps with front and rear reflecting. $451.75 $310.00
12SXQ Same as above but with halogen style outer bulbs. $480.75
CTS1S California style with front steady burn Par 46, rear amber flashing Par 46. $560.75
----------------------- You must order one of the following to mount all Twinsonic models-----------------------------------
12HK*3 Hook-On Mount $113.25 $64.25
12G Gutter Mount $113.25 $64.25
12P Permanent Mount $103.00 $58.50
12HG High Gutter Mount $116.75 $66.25
EBK*3 Extension bar kit for above mounts for use on 12, 12F, 12X and CTS1 $36.25 $27.75
----------------------------------------Conversion kits for Twinsonic------------------------------------------------------------------
GLCK Gutter to hook-On Kit $85.25
DMCK Dual mirror conversion kit $69.75
12XKF Converts model 12X to model 12F $84.75
12KF Converts model 12 with tall cascades to model 12F $119.50
------------- ** Visibeam cutout for speaker grill available at no extra charge if specified at time of order.-------------
----------------------------Dome size and mounting hardware common to model 12, 12M and 12S--------------------------
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