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Soprano signature??? What are these?

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Today I was at my favorite tech's shop--Bristol Electronics--when a couple brought in some old and worn McIntosh componenets and a pair of speakers. Tim is an authorized Mac repair center but speakers aren't exactly his thing so he took a look, determined the woofers in one speaker were shot and phoned Bill LeGall. Bill's advice was to just get some new drivers from PE. So I volunteered.

These are interesting but unknown. No identification of any kind except "Soprano Signature" handwritten on the baffle. I googled it and nada. Pulled one 5" woofer and it's pretty impressive. Almost 2 pounds, but no markings on either woofer in one speaker. Tweeters are Audax HD13D34H. Ported, but tightly packed with polyfill (it's even stapled to the back of the baffle around the drivers). One binding post was pulled out and separated from the wiring inside, so that will need repair.

I need to find some woofers. Bolt pattern is 5.25" diameter. Maybe Dayton Audio DC130A-8 would be a good replacement. I'm not even certain that these are 8 ohm nominal. It will be interesting.....

Soprano signature resized.jpg

Soprano resized.jpg

woofer resized.jpg

audax tweet resized.jpg

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Very odd.

There's no stickers on the other 2 woofers?

The dust caps look like Peerless or ELAC but the chassis' look like KEF B110 or Dalesford D30/110.

The surrounds look like rubber. Are they?

The DC130A-8 drivers might be OK but if the mystery woofer's response is anything like a B110 the crossovers might well need some modifications.

Great tweeters!

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Hey Chris

Thanks for your comments. These things are so odd I didn't expect any input. I want to test the other speaker before inspecting the drivers but there were no markings on the 2 woofers from the first speaker. 

Yes--the surrounds are rubber. I will be checking DCR and will also sketch the xo.

Good to know the tweeters are great. The woofers do seem like quality items as well. As mentioned, nearly 2 pounds each, with massive (for their size) magnets. I'm hoping the Dayton DC130A-8 drivers are appropriate. They seem pretty good and won't break the bank.  There may be a Peerless that would work but they are more expensive. Maybe make a complete change and go with HiVi M5N. Dunno. More research is needed.

Kent

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I actually spend most of my time with older British speakers so I have some experience with B110's and their ilk.

Generally speaking those 5.25" drivers did have rather large magnets which is another reason I thought they were English. The Daytons might be fine but it depends.

I'll be keen to see what the crossover looks like. Some of the BBC/KEF crossovers are very specific to the drivers used and will sound awful with anything else. Look up the LS3/5a crossover. Yikes!! They were that way because the Bextrene coned drivers had an uneven upper end. Properly adjusted they were incredibly natural with vocals which was a big deal at the BBC.

Those tweeters are the big brother to the famous Audax 12X9 one of the earliest great 1" dome tweeters.

Chris

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Thanks Chris

I looked at some of those Brit mid-woofers and I do see the similarity. If this is your thing, maybe a shot of the unusual lugs on the speakers will help ID. A Google search turned up lugs like that on KEFs.

I pulled one crossover but have not had a chance to de-solder the capacitors. I assume what's here is a 6-ish uF mylar with some sort of bypass cap. Total value 6.5uF

Have not measured the inductor yet.

Here's a crude sketch of the xo.

Soprano woofer3.jpg

soprano cap resized.jpg

soprano xo.jpg

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Kent,

I think these may be DIY speakers. The neat-o crossover construction and the fact that it is a 1st order series crossover makes me think homemade. Usually the KEF/BBC way was to use 18db or least 12db parallel. It looks like it is set for about 3.5KHz which is about right but that wouldn't do much for the rising highs of the woofers.

That input lug IS very British but I don't think it's a B110. I can do some more research to try and figure out what those drivers are but it really doesn't matter if they have to go anyway. Assuming that the coil is the right value, you probably could use those Dayton drivers. It would take some work to figure out what their tuning would be in that box. The other thing is the rubber surrounds on the vintage Brit drivers are stiffening up so the Fs and Qts are going up which totally ruins the enclosure tuning anyway.

Chris

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Chris

Thanks for informing me about Brit speaker drivers. I pulled the other 2 woofers and the surrounds were a mess, one VC was open and the other one sounded awful. So.... I'll order 4 Dayton Audio DC130A-8 5-1/4" Classic Woofers. They'll fit--I need square frames--and I think they'll work with the tweeters. I'll post a revised xo sketch (somebody please check my work). The unknown cap is a 0.33 bypass and the coil is 0.25mH. The grille has a double layer of cloth over the tweeter. Maybe to attenuate it?

Speaking of grilles, one particle board frame was broken from when it was removed previously and I broke the other one getting it off. So the frames have to be repaired and I'll install new grille cloth while I'm at it/ PE is temporarily out of the brown, so it wil be a while.

Kent

 

Soprano xo schematic 2.jpg

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It will be interesting to see how it sounds to you. Do you have any measuring gear like a mic?

This, by the way, is the "approved" 😉 method for drawing series crossovers. It looks like this one is at about 3KHz.

I drew the coil as an iron core. Just take off the 2 parallel lines if it's air core.

Were there any labels or anything on the other 2 woofers?

Soprano.png

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thanks Chris 

No marks on the woofers 

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Back from a short trip. So in addition to all 4 woofers being shot, one tweeter is toast. Beginning to wish I hadn't volunteered to repair these--they're a total disaster. Should have checked the tweeters sooner.

As I suspected, the owners have a sentimental attachment to these so I had to be careful about presenting the options. And sure enough they do want them restored, so.... found an NOS Audax HD13D34H on ebay. It was the same price as a new Audax TW034X0 from Madisound, which is supposed to be the direct replacement for the earlier model but I figured better to have the 2 tweeters match.

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If you haven't ordered the woofers yet, I would say don't. Unless price is no object this isn't worth it.

https://www.madisoundspeakerstore.com/audax-soft-dome-tweeters/audax-tw034x0-1.3-textile-dome-tweeter-by-aac/

And you should get two because they aren't exactly the same as the original model.

With a 6db per octave crossover even at 3KHz you can't just stick in a "normal" 1in. dome tweeter. This might be OK but because it is 4ohms you'd have to change the crossover cap and maybe add a resistor. There may also be some impedance issues at the crossover.

https://meniscusaudio.com/product/sb-sb29sdac-c0004/

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Hi Chris

You replied while I was revising my post.  I did see those tweeters at Madisound and had the same thought about it not matching so I bought an NOS original off the 'bay. 

The Dayton woofers are inexpensive and I'm hoping they will be good replacements. I spoke to the owner of these speakers today and did offer the option of just tossing the whole thing but he and his wife are very eager to have these working again, after decades of sittting idle. The speakers have value to them, so I'll forge ahead.

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Are the owners sentimentally attached to the towers or to the sound?

If that many drivers are gone, it's likely that they haven't actually heard the original sound for years.

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10 minutes ago, genek said:

it's likely that they haven't actually heard the original sound for years.

Agreed. I'm sure no one can remember what speakers sounded like decades ago. They like the "speakers", meaning the cabinets.

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Just out of curiosity, are the owners elderly? I was thinking that maybe "those darn kids of ours" nuked them rocking out. Those wouldn't have had too much volume capability.

The sound should be close enough with the Daytons if it's been that long since they heard them.

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Hey! Define "elderly"! I'd say they're a little older than me so, yeah.

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Jeez calm down!😜

I'm 68 and if the corona virus doesn't get me, moving around Altec Valencias and Rectilinear IIIs just might.

Sadly, my KLH 22's and 14's just don't sound as good no matter how much I love them.😢

If anyone wants to donate some KLH Fives to the "save Chris' back" cause it would be welcomed.

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That was meant as a joke but guess I needed to add a 😁

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Woofers should arrive tomorrow. In the meantime I fixed the damaged xo, glued the broken grille frames and filled some broken particleboard on the baffle. All the drivers were glued in with silicone caulk so pulling the drivers took some of the particleboard. And the grilles were mounted on wood dowels but also glued, so one frame was broken and I cracked the other trying to remove it 😠

I'll be re-covering the grilles but thought this was odd: A doubled layer of grille cloth over the tweeter (so 3 layers total). I suppose this is to attenuate the tweets? Analogous to AR & KLH putting fiberglass over tweeters? I'll have to do some listening when the new woofers are installed to see how these sound with and without the grilles.

3 layers.jpg

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Got the Dayton Audio DC130A-8 Classic Woofer Speakers installed. I was concerned because the cutout diameter. According to PE is 4.72" and these boxes have 4 3/8" holes but the drivers dropped right in. The originals had been glued in with silicone caulk so I scraped that off as best as possible and used PE Speaker Sealing Caulk with the new drivers. The name of that caulk is "Kent". Cool.

Temporarily wired in a spare tweeter for testing and everything works. The new tweet should arrive in 2 days. The brown grille cloth is backordered so that may be a while. Still need to work some more on the corner bash.

So how do they sound? Good for their size. I couldn't use my usual reference AR-91s to compare to these little guys so I used my Cizek KA-1s and the Sopranos did very well. I may haul out my AR-4x's for another comparison. The Sopranos are a bit bright, so that triple layer of grille cloth helps but I found myself turning the Treble down on my preamp. It may be that I'm so used to the "AR/KLH sound" that anything else will sound bright. OTOH my septuagenarian ears are incapable of hearing much beyond 10k so as far as I know I may be really pissing off the neighborhood dogs with these speakers. Wish they had level controls but I'm not going to add them. Any of you crossover gurus have ideas about a simple, reversible way to tone down the tweeters?

Kent

PS: Roy suggested adding an L-pad temporarily, adjusting the level by ear and then measuring the series and parallel resistance. I may give that a try.

sealer.jpg

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It's true, AR's were balanced to sound like you're half way back in Boston Symphony Hall. KLH's put you about a third of the way back. With Advents Mr. Kloss moved you into the first quarter of the audience. Boston Acoustics are about the same as Advents just cleaner sounding.

Hard to say what the best balance would be. The owners might like it brighter. The Dayton woofers may not be as efficient as the originals. Because of the series crossover you can't just stick in an L-Pad. Referring to your second drawing of the crossover, I would insert a 3 ohm, 10 watt resistor between the tweeter plus and the coil. If that doesn't make sense let me know and I'll redraw it.

I really don't like series crossovers.

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Thanks. Roy also suggested trying a 3 ohm although he said it will lower the xo point. Worth a try.

In the meantime I was not satisfied with the Famowood corner patch so I cut some veneer. Still have to trim and stain. Won't be as pretty as Glenn's but better than it was (I hope)

corner patch 2.jpg

corner patch.jpg

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Series crossovers are more tolerant of driver impedances.

The resistor will change it but less so than a parallel network.

Are you going to use velcro for the grills?

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yup 

The crossover with the pulled-out banana jack was so stressed that a cap lead broke as I tried to move things back in place. So I replaced the 6.2uF mylar + 0.3 bypass with two 3.0uF mylars and 0.47uF bypass.

new caps.jpg

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