| Duo |
Today I was out and about and picked up a pair of these speakers at the second hand shop. Looking through the grille cloth revealed a single 12" driver with a vented dustcap and accordion surround. It looked a lot like many Altecs I'd seen.
Unfortunately, these are some cheap 'who-knows-what' speakers.
I'm trying them out with the backs off and stuffing out and driving with a transconductance amplifier. With some tweaking I think these could really sound alright on a transconductance amp.
What I'd really like to know is; who made them? Where did they come from?
They sure look cheap!
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| bigwill |
| That magnet looks just like the magnet from a wharfedale driver I had. |
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| dnsey |
| The magnet is similar to Wharfedale (but slimmer for its size0, but the rest is nothing like one! |
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| Geoff H |
That square magnet should give it away. Wharfedale is the only one I am aware of. Agreed, nothing Wharfedale about the rest of it.
What's on the logo on the grill cloth? The cabinet should keep someone warm for about 20 mins.
Good drivers to tweak though. Treat the surrounds, remove the shining dome, and treat the cones. Probably best on OB, as big as you like to go.
Have fun with them. Geoff |
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| chrisb |
| I could be all washed up, but the grille cloth and enclosure margin details remind me of vintage (late 60/early 70's) Norecsco speakers, in which case the drivers could be OEM RSC (Radio Speakers of Canada) |
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| Duo |
They do look kind of noresco/wharefedale/who knows what..
I was contemplating removing the dustcap to see what they sound like... Open baffle is exactly what I had in mind, along with an amplifier adjusted for critical damping.
I find that the suspension is extremely stiff on these; far stiffer than typical drivers of their sort. They are terribly thin in the bass region no matter what I do, I'm thinking that if the suspensions were treated with something to soften them up, and broken in for a while, they may be soft enough.
They are essentially all mid-range, with the ability to do nice high end if driven a little strong in that range. (the transconductance amplifier helps here along with the bass.)
Keep the ideas coming, hehe. ;)
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| Geoff H |
OK Mod time. Can you take a close up shot of the surround. And if possible, one with the light coming in from behind. I want to see how translucent the rolls are. See if they are like this.
Where's Dave? He might want that Ultimate firewood.
Geoff |
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| Duo |
Here are more pictures. This time, macro shots.
There are two of the surround, one with flash and the other without, and one of the dustcap center.
The surround is opaque.
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| Duo |
Upon closer inspection, the surround is simply an extension of the cone paper itself, not a separate attached piece.
It is very heavily doped with a mildly sticky green coating, not unlike what you see on many other drivers. It's a bit shiny too. |
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| planet10 |
| quote: | Originally posted by Duo
They do look kind of noresco/wharefedale/who knows what.. |
I've got some of those... mine are made by CTS (in 1974) ... do yours have a code 137 9999
BTW... older Norescos are very worthy of scooping up. Yjr 2 smallest (1 way) have Philips 5 or 7" with whizzer, larger ones Isophons. One of the bigger ones have 8x12" coax.
dave |
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| Duo |
Hahaha, you would have a set of these.
Mine are 137 7413 and 137 7414 respectively.
They also have 5812484 written on each magnet.
Do you know anything about them? Besides the obvious fact of their utter cheapness. |
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| planet10 |
| quote: | Originally posted by Duo
Mine are 137 7413 and 137 7414 respectively. |
The 137 is the CTS OEM code. Made in April 1974. I put them up on the shelf & haven't done anything with them. I could pull em out and measure them.
And even with there "cheapness" they might sound just fine with a little teakage. Likely open baffle material.
dave |
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| Duo |
For sure open baffle, I tried that the minute I got them home and that was the only way they would perform at all.
I really feel they need a serious breaking in. Stiff as hell.
If you do get around to measuring them, please send me the parameters :)
Anyway, I'll keep tinkering with them and see what I get. Would you say it's best to rip these silver caps off as others have suggested or leave them on? |
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| planet10 |
| quote: | Originally posted by Duo
Would you say it's best to rip these silver caps off as others have suggested or leave them on? |
My guess is that they would change from FRs to midranges without.
dave |
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