View Full Version : Mystery Speakers???????? ALTEC? Trusonic - Tru-Sonic?

06-16-2011, 02:35 PM
Hello -

I recently came across this pair of speakers and have been unable to determine who made them. Any help would be greatly appreciated. They are quite large and heavy - measuring 27 x 20.5 x 14" They are three ways - trusonic 15 - spelled tru-sonic in the casting. and trusonic 80fr. I have noticed other posts with ALTEC speakers having similar drivers?








and the link to the entire photobucket album


Harvey Gerst
06-16-2011, 06:50 PM

Steve Schell
06-17-2011, 12:32 AM
Calderdoran, we have only sketchy knowledge of the "Tru-sonic" speakers of this period. The Stephens Tru-sonic Manufacturing Company was established as early as 1938 by Robert Lee Stephens, former draftsman at MGM studios and participant in their groundbreaking Shearer Horn Two Way Loudspeaker project along with Jim Lansing, John Hilliard and others. Stephens left MGM and built up his very successful enterprise through the postwar era until his death in 1957. After that, Bert Berlant of Concertone tape recorder fame ran the company for awhile, then it passed to the people associated with the Standel guitar amplifiers in Temple City, CA for a time, then finally to the people behind Utah speakers, by then located in Indiana. It is interesting that your speakers contain drivers from both latter locations/ownerships. These drivers were built in the earlier tradition of strong Alnico V motors and cast baskets, but have no particular connection to Altec Lansing aside from this general similarity in design.

rudy sesztak
06-17-2011, 05:45 AM
It looks like a home built system,using Stephens Trusonic woofers,and mid range. The tweeter has to be an EV t35,or a Klipsch tweeter,that was made for them by EV. I hope this information helps.- RUDY SESZTAK

06-17-2011, 06:23 AM
Hey thanks for the info - I was not sure if they were stephens because of the spelling of trusonic - tru-sonic - and it does not say stephens anywhere I can see on the speakers. It may well be a kit/homebuilt - but very nicely done - just need to clean up the outside a bit. Also one more bit of info - I hooked them up last night and when I dial the control knobs on the rear - there is crackling - otherwise they sound quite nice. Are these things desirable ?

Thanks -


06-17-2011, 06:24 AM
Oh and I forgot - any guesses on the "vintage" of these speakers?

Thanks -


Don C
06-17-2011, 12:04 PM
Since the search function is currently broken, I'll add this link to an earlier discussion that may be useful.

06-17-2011, 12:54 PM
Thanks Don -

I did not see any dates - I am not an Audiophile just seem to have the knack in finding older interesting speakers - A year or two ago I bought a James B. Lansing c34 Corner Horn.

I am curious about dates for this latest find- 60s? 70s?.

Thanks Again


06-17-2011, 06:08 PM
The 8" and 15" look like bad recone jobs with Waldom parts.

The Trusonic fullrange 8" typically had a red cloth surround and a gold-tone aluminum dome.

Steve Schell
06-18-2011, 11:44 PM
I would agree with edgewound's assessment of inferior parts, though I think the cone jobs may be originals done by later incarnations of Trusonic rather than recones. The earlier Stephens-built versions were exactly as he describes. I have seen a number of these later drivers with their sick monkey green paint jobs and surrounds.

Dave, any guesses as to age are just that. Bob Stephens died in 1957, Bert Berlant ran Stephens Tru-sonic through the production of the original FR series until perhaps the early to mid 1960s. Your units built in Temple City and Indiana postdate that, though I'm unsure by how long. The builder of your speakers likely purchased at least some of the units used. Your FR-80s have scratched rear badges, which suggest to me that they have spent some time on the asphalt at a swap meet.

As Rudy said, your tweeters appear to be Electro-voice units. They probably have cloth and phenolic dome diaphragms and sound very sweet.

07-02-2011, 03:25 PM
Thanks for all the info - I am enjoying the speakers reconed or not.


Altec Best
07-21-2011, 10:08 AM
I hooked them up last night and when I dial the control knobs on the rear - there is crackling - otherwise they sound quite nice.

The pots are dirty on the Crossovers.If you can get some De-Oxit D5 and work it into the pots while turning the knob back and forth 50-100 times and spraying it a few times you should be able to get the crackling out of them.Depending on how dirty you may have to do this every few months or so.Or you can replace the pots and be done with it. ;)

04-04-2015, 09:03 AM
Hi, hope I can add a little info to this site even though the post is older as some will find it down the road. Evidently Utah bought up the Trusonic line in the late 60's as I recall. From what I can tell the black frame and edging came from this era of the last of the Trusonic's, or the beginning of the Utah production, maybe Utah wanted a new look or ran out of the red goop. The later run from the early 70's and on were green and I believe that Utah was responsible for the 120W/150W and 80M versions which had the paper center caps and designated as only woofers and the M for midrange.
There was a manufacturer named PAS here in Los Angeles in the early 70's using the Trusonic parts, they were a group of Aerospace Engineers I believe. The company never made it and I have no idea where they went off too, though there is a Musical Instrument Co. with that name but if that had anything to do with them I am not sure. These do not appear to be from that company, my guess is someone swapped parts from some other brand cabinet and used the EV horn tweeter or maybe it had the tweeter already in it.
All of the speakers made by Utah were like the originals and have flat ribbon voice coils with alnico magnets, some say Utah on them with the name Trusonic. Hope this helps, Jay

SiCo Amps
04-16-2016, 07:00 AM
... and I would like to share my thoughts.

First of all, these are not "one off" home brews. They may very well have been kits, but the fact that I found an identical pair in an old TV repair shop around 1995, makes it a commercial item.

My pair had a bad EV tweeter and a midrange that was suffering from bad voice coil rubbing. I sold both pair a long time ago. However I kept the 150W, which by the way, are GREAT woofers.

Going from memory here, as I recall, the crossover consisted of a single capacitor feeding the tweeter. Both woofer and midrange were wired in parallel. I suspect that they are both 16 ohm speakers. The DCR on the two FR80 was 5.6 and 5.1 ohms. I currently have a pair of older OEM FR80 that are 8 ohm drivers and came out of a Ampex studio monitor. They measure 4.8 and 4.8 DCR. The big 150W woofers measure 8.2 and 8.2 DCR.

I suggest that these driver come from the Tru-Sonic period of the mid to late 1960s. My Stephens manufactured "Ampex" FR80 are clearly early OEM jobs. They do not have the painted frame and have the pristine gold dust cap and red surround. The two that came with the speakers in question, are as pictured in the thread, aluminum dust cap and black surround. Pretty sure that this would be a late sixties version. The woofer however, while it looks like a green surround, I suggest you look more closely - or maybe remove it and look from behind - you will see that the green color is provided by a green painted on dope. At least in the case of my pair of 150W, the actual cloth surround is RED - with the green dope painted on. The woofer are outstanding and should not be taken lightly... which is easy, since they are very heavy. ;)

SiCo Amps
04-16-2016, 07:21 AM
... I can see the RED in the woofer surround peaking through. Also, note the location of manufacture on the magnet badge. :applaud: The FR80 is made outside California... at a later date. But of some interest, note the picture of the FR80 from behind... that is a RED surround covered with black dope on the front. ;)

BTW, I heard many years ago, that Heathkit may have offered for a short period of time, I speaker kit that fit this description, but I have not been able to collaborate that as fact. In any event, the drivers used in these speakers were not chopped liver.

04-16-2016, 05:49 PM
Thank you for your insite and welcome to LHF!

10-02-2016, 12:16 AM
Thanks for all the info - I am enjoying the speakers reconed or not.

I am from Southern California and had Trusonic speakers as a teenager around 1968-70. Moe's Old School Audio had your speakers for sale, or so it seems, and I picked them up and am building new enclosures for them, and I am going to replace the EV tweeters with JBL tweeters. It's a small world. Hope this gets to you after all these years. Best to you, Dan

10-22-2016, 08:30 AM
I own a pair of late 50's/early 60's Stephens 3 way speakers that look much like JBL Soveriegns.Mine are loaded with Stephens w150 woofers/M-8 mids/5KT bullet horns.These are part of my vintage reference system along with 50's Fisher eq,Fisher 50A mono block amps paired to 400c Fisher tube preamp/Fm100c tube tuner.Nice to see others enjoying the fantastic sound these Stephens are know to produce