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    World Designs speaker KIT based on the Dynaco A-25 "aperiodic" speaker - link

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    Bob Latino
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    World Designs speaker KIT based on the Dynaco A-25 "aperiodic" speaker - link

    Post by Bob Latino on Wed Apr 22, 2009 1:19 pm

    World Designs in the UK now has a speaker kit based on the original Dynaco A-25 "aperiodic" speaker. Check it out at the link below ..

    World Designs A-25 speaker kit

    Bob


    Last edited by Bob Latino on Sun Jan 05, 2014 9:20 am; edited 1 time in total

    TXinD76121

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    Re: World Designs speaker KIT based on the Dynaco A-25 "aperiodic" speaker - link

    Post by TXinD76121 on Wed Apr 22, 2009 6:30 pm

    BTW, I talked to World Designs, and they can actually ship more cheaply than 96 British pounds, which is (today) $140 Shocked and thus rather absurd. If you get the cabinets from them here in the U.S. the shipping will still be pretty expensive. But I advise contacting them first if you want to get the kit, and see if they can get the shipping cost down for you.

    Listens2tubes

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    Re: World Designs speaker KIT based on the Dynaco A-25 "aperiodic" speaker - link

    Post by Listens2tubes on Sat Apr 25, 2009 3:59 pm

    I've seen quite a few originals while trolling ebay as of late. Wish I had room for a "B system". OH! Embarassed That would our "home theater" in the family room.Rolling Eyes

    TXinD76121

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    Re: World Designs speaker KIT based on the Dynaco A-25 "aperiodic" speaker - link

    Post by TXinD76121 on Sat Apr 25, 2009 4:58 pm

    I've been listening to a vintage pair of late, perched atop my Tannoy floorstanders. A-25's still do pretty well because the rubber woofer surrounds don't rot away as has happened to so many other vintage speakers of that era. Musically, they have some flaws by today's standards, mostly relating to the not-very-refined tweeter and too-simple crossover. But they still have the qualities that made them the best-selling audiophile speaker of all time: coherence, clarity, and taut, descriptive, if slightly dry bass.

    Plus, I got mine for less than $100.

    I like them well enough that I'm seriously considering getting one of the updates, "sight unseen" (sound unheard?).

    Mike

    DesignInc

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    Re: World Designs speaker KIT based on the Dynaco A-25 "aperiodic" speaker - link

    Post by DesignInc on Tue Sep 28, 2010 2:39 pm

    At that World Design sight, I noticed they say the original Dynaco A-25 was designed to be on the floor tight to the wall for best response ... counter to todays raised stand approach. FYI

    David

    DesignInc

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    Re: World Designs speaker KIT based on the Dynaco A-25 "aperiodic" speaker - link

    Post by DesignInc on Tue Sep 28, 2010 2:45 pm

    Bob:
    I have an original set of Dynaco A25’s that I got for $5 in xtra-nice shape and they sound pretty good too. But I’ve read a lot about capacitors that are 40 years old and probably low quality to begin with, have lost character…istics. Should I replace those 5uf 50v caps?

    Was planning to use the Solen Fast Caps 4.7uf paralleled with a 0.22uf 630v to create a 4.92uf that would be close to the original 5uf.

    Solen metallized polypropylene Fast Cap 4.7uf and 0.22uf 630v would be $18/pr
    AuriCap 4.7uf and 0.22uf 400v would be $60/pr
    AuriCap 4.7uf and 0.22uf 600v would be $106/pr

    The main dilemma is that the Solens would probably be the closest to OEM sound but ... my other thought was I could probably make the treble sound better than original with the AuriCaps. Some say the heavier 600v vs 400v windings make for a richer/smoother sound, does that make sense to you … or is it esoteric bs or making a silk purse out of a… etc.

    Anything else I should consider replacing?
    Your thoughts...?

    Thanks, David

    Bob Latino
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    Re: World Designs speaker KIT based on the Dynaco A-25 "aperiodic" speaker - link

    Post by Bob Latino on Tue Sep 28, 2010 3:05 pm

    Hi David,

    One of the biggest improvements you can make in any pair of vintage speakers is replace ALL the capacitors in the crossovers on both speakers. Of the caps you mentioned, the Auricaps are probably the best but are expensive.

    Re: the 400 vs the 600 volt caps. I think that the lower value caps will probably break in quicker but personally I don't think that the increase in voltage capacity (to 600 volts) will sound much different than the lower voltage rated caps. I would go with the 4.7 uF 400 volt rated Auricaps with the .22 uF 630V caps as you have mentioned. After you make the capacitor switch, give those speakers 100 - 200 hours of play time before you form any opinion of the sound.

    Bob

    Luddite

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    Re: World Designs speaker KIT based on the Dynaco A-25 "aperiodic" speaker

    Post by Luddite on Wed Sep 29, 2010 11:20 am

    FYI: World Designs was recently sold by it's former owner Peter Comeau, and is now under new ownership. Presently, they have reintroduced several of their tube amplifier & tube preamplifier kits. I understand that they hope to resume offering speaker kits, but since they are no longer the British distributor for SEAS speaker components, they are, unfortunately, putting this on hold for the present time. Here is the new link to World Designs: http://www.world-designs.co.uk/

    Charlie

    P.S. For those who might be interested, Madisound Speakers in Wisconsin has both of the SEAS drivers used in the World Designs WD25A speaker. The woofer model is A26RE4-H1411 and the tweeter model is 29TFFW-H1318 (or an optional and more costly, model T29CF001-E0038). Madisound's link is: http://www.madisound.com/

    P.P.S. If anyone would like a copy of the original WD25A design article, just send me a PM and I will email it back to you.

    Luddite

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    Re: World Designs speaker KIT based on the Dynaco A-25 "aperiodic" speaker - link

    Post by Luddite on Sat Oct 02, 2010 7:04 pm

    Would anyone have any thoughts or comments about constructing the WD25A's as "WD35A's"? In other words, building the A-35 cabinet from the original Dynaco plans and then installing the same SEAS drivers as used in the World Designs model WD25A.

    I suppose that I could construct the WD25A cabinets from the HI-FI World articles, but thought it might be intriguing to try the A-35 cabinets instead.

    Charlie

    DesignInc

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    Re: World Designs speaker KIT based on the Dynaco A-25 "aperiodic" speaker - link

    Post by DesignInc on Mon Oct 04, 2010 12:44 pm

    Hey Charlie

    My first reaction after reading WD's articles about construction and the XL-crossovers ie: stage three crossover, it sure sounds like they did a lot of sophisticated testing to create the WD25-XL unit. I'll bet it sounds pretty good.

    BUT ... I'm surprised they went to all that work and didn't base it on the Dynaco A-35 with it's internally vented woofer and Greg Dunn says "different crossover" which from everything I've read was superior. Or even the A-40XL with the XL 1' tweeter.

    My 2 cents - add that baffle and internal slot and make the A-35, and without that front vent it would be easier to build anyway.

    I assume you saw Bob's info on the cabinet:

    http://dynacotubeaudio.forumotion.com/basket-f2/dynaco-a-10-a-25-a-35-40-speaker-schematics-photos-t133.htm

    David

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    Re: World Designs speaker KIT based on the Dynaco A-25 "aperiodic" speaker - link

    Post by Luddite on Mon Oct 04, 2010 5:47 pm

    DesignInc wrote:Hey Charlie

    ...My 2 cents - add that baffle and internal slot and make the A-35, and without that front vent it would be easier to build anyway.

    I assume you saw Bob's info on the cabinet...


    David

    David,

    Thanks for your reply and suggestions. I agree that it would be simpler with the internal vent. To answer your question, yes I've saved the A35 cabinet drawings that Bob posted, which will be very useful when I get the opportunity to build these. Probably not until next spring.

    Charlie

    Luddite

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    Re: World Designs speaker KIT based on the Dynaco A-25 "aperiodic" speaker - link

    Post by Luddite on Tue Nov 23, 2010 2:54 am

    I was fortunate recently in coming across a pair of NOS, SEAS 25F-EW 10" speakers. I believe these were the same as used in the Dynaco A-25XL series. I also obtained a couple of "prototype" enclosures with the Scanspeak "aperiodic" vents already installed. I am in the process of finishing the cabinets and should have these functional within the next month. I will be ordering a pair of SEAS H1189 tweeters soon.

    Best Regards,
    Charlie

    quad

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    Re: World Designs speaker KIT based on the Dynaco A-25 "aperiodic" speaker - link

    Post by quad on Thu Nov 25, 2010 4:08 am

    Replying to one of the older posts on this thread -
    The Dayton 5.1 uf cap from PE has been recommended elsewhere to
    recap the A25 crossover.

    http://www.partsexpress.com/pe/pshowdetl.cfm?&PartNumber=027-232

    Alternatively, Parts Express part number 027-554 is a Solen 5.1uF.

    Luddite

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    Re: World Designs speaker KIT based on the Dynaco A-25 "aperiodic" speaker - link

    Post by Luddite on Thu Dec 02, 2010 11:30 am

    I recently purchased some speaker components, etc. from Gary at Annandale Acoustics and I would like to compliment him on his helpfulness and on the high quality of service he has provided. All items were of excellent quality and IMHO they were very reasonably priced. I plan on doing further business with Gary and would highly recommend his company to all!

    http://annandaleacoustics.com/

    Best Regards,
    Charlie

      Current date/time is Thu Dec 18, 2014 9:22 am