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Unitra (made in Poland) speakers

BmWr75

BmWr75

Top octave? pfffffftttttt
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A co-worker of mine bought these new at Opus One in Pittsburgh, probably in the late 1970s. She brought them to me to take a look at the other day. The look pretty well made with solid cabinets, probably in the 30 lb. each range.

The woofers have pleated cloth surrounds, so no refoaming needed. Hooked them up and immediately noticed neither tweeter is playing. By the rear speaker terminals there appears to be a fuse holder. I've had no success getting it open so far, the plastic is brittle. Will pull a tweeter and see if it has continuity next.

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Both tweeters are blown (no continuity, infinite resistance). Luckily, they are Realistic dome tweeters, Cat. No. 40-1276A. Wonder is a replacement is available?
 

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Looks like that black round socket is for a custom plug. I would suspect that it may have had an external crossover and that is the entry point for the tweeter signal? I'd pull a drive and look at the internal wiring ...
 
Damn-nice-looking speakers...

Are the woofers Radio Shack jobbies as well, or do you think they're from a different maker?
 
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I pulled one woofer. They are marked Tonsil - Made in Poland. Tonsil was the parent company of Unitra (or vice-versa) from what I've read.
 
More than likely that extra connecter on the back is just a DIN style audio connector.

Not an uncommon type of connector on European audio equipment.
 
JBL GUY said:
More than likely that extra connecter on the back is just a DIN style audio connector.

Not an uncommon type of connector on European audio equipment.
Click to expand...

That is what it is. It connects directly to the other set of screw type connection posts.
 
Interesting that the speaker has a tweeter polarity reversing option right there on the back panel.

I guessed wrong on this one. The next post seems to clear it up. A jumper for tweeter level.
 
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I would suspect that it is for changing the level of the tweeter rather than the polarity, all though it is a somewhat unusual method.

If you note that in the picture of the speaker response graph, the graph splits into two curves on the high end, depending on + or -.

An interesting pair of speakers.
 
Hi, I remember these brands (Tonsil and Unitra). Unitra used to be making pretty good and affordable stuff at that time. There was a shortage of imported goods and this was good local brand.
In terms of connection it is common DIN audio connector used only to connect speakers. For signals it used to be 3-pin or 5-pin DIN in consumer equipment (even headphones).
 
Oh, I happen to know something about these. They are known locally as Unitra-Tonsil ZG40C/5 or C/8, depending on the rated impedance. Unitra was an association of Polish electronic manufacturers, started in the late 60s, ended together with the communist reign. These speakers date from 1979-1980. Made by the tons, exported by the tons. That may be surprising, but HiFi stereo gear was very popular in the gray, communist Poland of 1970s/1980s. Pretty much everyone who had an interest in music and stemmed from the middle-class would have a stereo system of decent quality.

The specs are as follows (from the service manual):

Rated power - 40W
Frequency response - 45 - 20000 Hz
Cabinet volume - 43 l
Crossover points - 1,8 kHz and 7 kHz
Weight - 20 kg

They are good speakers, not great. Unfortunately these Realistic drivers are obviously not original and you may have a hard time finding original units in the USA.
 
Emmm...

Sir, you e-mailed a Romanian vendor, not the Polish company.
Original midrange driver should be "GD 12/5/2", original tweeter: "GDWK 9/40"
GD 12/5/2 has not been in production since the 1980s. However, the updated version of GDWK 9/40 is still in production (as GDWK 9/80). You can buy it here (original Polish Tonsil distributor): http://www.e-tonsil.pl/index.php?p83,gdwk-9-80

I can ask them about shipping to the USA if that would be helpful to you.

Tonsil's webiste:
http://www.tonsilproducent.pl/
 
As Winters says, you probably should contact the Polish supplier. But if the Romanian vendor has in stock he should be ok as well.

Some more info regarding the loudspeaker:

The woofer: Unitra was the company name in the old days and it became later Tonsil so the woofer might be allready an original replacement.

Unitra (Poland) used to build loudspeakers for PIONEER as well.

The lower plug is indeed a DIN standard plug for loudspeakers. This was the original (1979) and only plug with the tweeter jumper. The screw type was later added.
 
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