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Vintage Radio Shack/Realistic Speakers?

Steve Smiley said:
Infantry Man, I think you got a really nice haul there!

Looking at the stack in the rack, you may have a very interesting receiver there. Technics has a line that used what they marketed as “New Class A” and it seems like that might be the tag on that receiver. It is well-received. Google “technics new class a” And you’ll see good info - here on AK and elsewhere, like DIYaudio.

Might have some other nice gets in there as well.

I think you’ll like the speakers as well. Do starters, they look great! Walnut veneer all around. They refinish very nicely. A couple tweaks I did to mine that made a big difference:

First, I added bracing in the cabinet. Big difference in the overall character of the bass and mids.

The woofers run without any inductors and are meant to roll off smoothly on their own. The tweeter is a cap only. Replace the original cap. Both woofers and tweeters run through the L-pad. The stock tweeter is disappointing. I replaced mine with a phenolic ring tweeter I picked up from Parts Express. I feel it is much nicer. Make sure, also, you check that both woofers are working. They are 16 ohm wired in parallel. When I played mine it sounded like they were working fine.
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Thanks for that , if I may ask , do you have any pics of the internal bracing you did ?
 
Infantry Man said:
Thanks for that , if I may ask , do you have any pics of the internal bracing you did ?
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Skip what I said about the L-pad. Only the tweeter uses the Lpad. The dual Lpad is on the Mach speakers. I made some updates on my original post for accuracy.

I’m looking for photos of the bracing now.

Smiley
 
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Isaac C. said:
Has anyone on here ever used a Realistic 40-1310 Super Tweeter with another speaker? Im thinking of pairing them with my Dynaco A25s.
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Free advice (and worth every penny :cool:). Skip the 40-1310 (which are overpriced today and really too sensitive for an A25 -- i.e., they will require substantial padding down) and seek out a pair of the R/S 40-1375 "leaf" (planar) tweeters. These were a "value engineered" OEM version, homage to, or ripoff of ;) some highly regarded JVC drivers of the early 1980s. Whatever they are, they are very, very sweet little drivers that serve quite well as "supertweeters" crossed in very high & first order, paralleled with the inputs of the loudspeaker to which one wishes to add some "air" :)

40-1375.jpg
upload_2020-8-10_15-40-9.png

source: http://www.radioshackcatalogs.com/html/1984/hr022.html

Here's one adding some sparkle to a 16 ohm Altec Valencia :) Time aligned 'n' everything :)

upload_2020-8-10_15-48-29.png
 
Woah, those are not original tweeters!

Are those the Foster horn tweeters (quick glance).
I think you picked this stuff up from someone who cared a little bit about what they were buying. Enjoy for sure!

well done!
 
Infantry Man said:
Thanks again Steve Smiley . I will pull one and get a pic . I should have picked a lottery ticket on the same run :)
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Pull the Lpad as well. You’ll want to see what it is crossing over at. I don’t think you can cross that I’ver low at all. I think it is rated at 5,000 Hz - 40,000 Hz, something like that. Let me see if I can find what the original tweeter was crossed at. I probably have a photo of the original cap.
This is fun!
 
Infantry Man said:
View attachment 1949855
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It looks like the original cap was a 4.7 uf. That high passes the tweeter signal gently at around 4200 Hz. really out of range for that tweeter, I believe.So that crossover point might not be great for that tweeter,

Anybody with 40-1310 experience? That question has been asked already today.

Looks like it is time for some research!

I'll look a little later tonight. I have some woodworking to do in the garage.

Regards,

Smiley
 
Steve Smiley said:
It looks like the original cap was a 4.7 uf. That high passes the tweeter signal gently at around 4200 Hz. really out of range for that tweeter, I believe.So that crossover point might not be great for that tweeter,

Anybody with 40-1310 experience? That question has been asked already today.

Looks like it is time for some research!

I'll look a little later tonight. I have some woodworking to do in the garage.

Regards,

Smiley
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It is indeed a 4.7 uf .
 
I think (???) 4kHz was the recommended/original XO in the add-on modules(?).
Maybe that's a synthetic memory, though :(

I dunno, I am sure someone knows off the top of his/her/their head what the XO components were in the original add-on 40-1310. I am also thinking I remember that they were actually second order?

There is a NIB pair (later ones, though, not Japan-made) in the basement someplace, but I don't think I have the gumption to find them, unbox one and open it up to see what the XO components are. Sorry. :confused:
 
So far , I'm surprised by the Optimus T-100 speakers , the upgraded tweeters are very bright , I took the l-pad down to 25% , good soundstage , surprising bass . Certainly not high end equipment , great for this old grunt .
 
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