loudspeakers

[leadtower]

Say Wa4swj; I looked up your link for the new Dyna A 25's. They are fantastic looking. They sell to North America; converting from Euro's it looks like they go for about 410$ Can I ask do you happen to know anything more about them? They might be right up the alley for the ST 35's.

[WA4SWJ]

Howdy!

Well, I wrote to Madisound and asked if they had seen them and if they were going to import them since they are a Seas distributor. I did get a response, but the only thing they said was that they are thinking about it. The gentleman that wrote me also said that the woofer they are using in the design is being obsoleted by Seas. So, I guess the speakers will eventually have to be re-designed for a new driver.

I also wrote directly to the company in England (World Designs I think) and I have not received a response. So, I don't know if these can be had in the US or not. They sure do look very cool and would probably sound even better than the original A25's.

Wish I had more info. I think they are fantastic looking! The magazine that reviewed them hinted that they are fantastic but their review is for subscribers only. And, I didn't find a link on how to subscribe in the US. Darn!

Regards,

[leadtower]

I looked through the site and they have shipping to North America listed. Also they offer kits but they don't have a specific listing for that set-up as a kit. I know the old 25's have a first order xover with just a cap and a resistor because I have a pair; but I wouldn't mind another brand spanking new 25's.
There is a phone number on the site; I wonder if it is worth a call?

[WA4SWJ]

Probably is - when I first looked at their site I couldn't find anything about shipping to the US. Looks like it's there now - of course I could have just missed it the first time I looked at it.

They look like speakers worth investigating. I would hope they would have updated the crossovers to something more modern. They almost surely did so they probably sound pretty good indeed. I'd love to hear a set somehow.

The other option of course is to work on a new crossover for existing A-25's and put it into the old speakers. I don't know if anyone has worked on that or even if it's worth the effort. Sure would be fun to work on it though. Wish I had the time and the analysis tools.

Regards,

[leadtower]

I checked the site again. they use upgraded passive parts in the xover. The price is 270$ plus about 100$ for shipping; and thats for parts only no boxes.
The drivers are upgraded obviously; they include all passive parts plus a special foam for the aperiodic vent and stuffing; I think long hair wool along with the speaker jacks. You can get the box flat packed too. Probably more money than building one here to ship. If I read you right thats a great idea; use your original A25 box and stuff it with the new components.
This may be a keeper.

[WA4SWJ]

Yes, that's the idea. Although, I am not sure the original drivers need replacing. Maybe just a crossover tweak or two. BUT - I am not a speaker engineer. I really don't know much about speaker design at all. I did replace the tweeters in one of my A-25 sets (I have 3 now) with Morel MDT-20's. I think they definitely sound better. Driving them with my Dynaco ST-70 clone with Shannon's board is wonderful.

World Designs now have the first of an apparent 3-part article posted called "Technical Information". That definitely was not there a few days ago. If you haven't seen that it's definitely worth checking out. Next month they will issue the second article with info on the crossover and then finally the wood details.

Can't wait to see it!

Regards,

[erichayes]

Hi All,

A couple of thoughts . . .

The only "improvement" Bud and I made to the A-25 crossovers was to replace the electrolytic 4.7 µF cap with a Solen 4.7 µF poly. One of the reasons the A-25s sound so good is due to the minimalist first order crossover. When you start throwing inductors and resistors at a crossover to compensate for the mismatching of the drivers, you create more problems than you solve. Seas took great pains to physically match the woofer and tweeter so they'd cross over naturally. The cap's in there primarily to protect the tweeter from excessive low frequency energy burning out the voice coil. If you're interested in experimenting with crossover frequencies and slopes, put a second set of binding posts on the back and wire the tweeter directly to them (the woofer's already wired directly to the existing posts). Now you can hook up passive components or biamp the speakers using an active crossover. I recall seeing a circuit for a tube crossover a couple of years ago on the net, and I'm sure there's probably nore now.

The Brits seem to be fond of using wool for loading speaker cabinets--it's by far the material of choice for loading transmission lines--but there's a downside. Back in the 70s, a freind of mine decided he wanted to build some transmission line speakers, using instructions from England (where XL systems are much more popular than over here). Since the parts list called for so many ounces of wool to load the line, he logically figured he could get some from one of the local 4H kids in the area. Builds the cabinet, stuffs the line with the wool, drags 'em into the living room and fires them up. They had such an effortless and infinite low end that I became an immediate convert. I go home, he leaves town for the weekend, gets back Sunday eve, and I get a phone call: "Can I stay at your place tonight?" Well, he's only 3 doors down, so I walk over to his place to find out what's up. He forgot to wash the wool. It smelled like a shepherd had led his entire flock through my friend's living room.

Needless to say, he spent the night at my place, the speakers were removed to the garage, another pair was eventually built, and this time he used fiberfill pillow stuffing. I'll never forget that smell . . .

[TomMcNally]

It smelled like a shepherd had led his entire flock through my friend's living room.

hahah - thanks for the laugh

I have a pair of original A-25's and know of another pair I could snag. They sound great with the original ST-35 and ST-70 (Triode's Driver) I need to listen to them with some of the other amps. I think I have 2 sets of speakers for every room in the house now.

[WA4SWJ]

Tom,

Glad to hear someone is like me in some respects. I'm being overrun with amps and speakers and loving every minute of it.

Eric,

I think I've seen a post you did on the caps in the A-25's here. I might do that next. But to tell you the truth, I love the way the A25's I'm listening to right now sound with those Morel MDT-20 tweeters. I don't have any intention of messing around with drivers or damping materials in the enclosures. They sound pretty darn good to me as they now are. But the cap would be worthwhile. I'll order a couple.

Regards to all and have a great audio weekend wherever you are!

[erichayes]

Here's one.

[erichayes]

You forgot this one, Shannon.

[Shannon Parks]

Thanks, Eric!