Open Baffle Epiphany!

[Poultrygeist]

Nice. The OB world was saddened to see Hawthorne stop production. Hope Daryl is enjoying his retirement.

 

[Miron]

Miron, can you share more details about how your leather OB’s are made? How thick is the foam? How big are the wood circles that support the drivers? Maybe you could show a picture from the back side of your big leather OB’s.

This idea of leather as a surface treatment fascinates me.

Thank you Miron.

Hello Goggle, the foam is 3cm. Now I have not wood with the polystyrene baffle. The driver is screwed on the polystyrene. And I plan to glue the leather with the polystyrene.

 

[Poultrygeist]

I've enjoyed a variety of tweeters over the years but the finest OB tweeter I've experienced so far is the Planar dipole B&G Neo 3 PDRw-2. B&G stands for Bohlender Graebener which went out of business for awhile when the owner passed away. I bought the two versions of the Neo 3 from PE shortly before they ceased production. Happy to report that B&G's are back in production and PE is carrying them again. They come with a back cover that makes them appropriate for box speakers. The cover is lightly glued on and should be removed to get the benefit of OB rear radiation. In the picture you can see how a blade is used to gently pry off the back cover. The round mount is extra and not necessary but it does allows for easy use with box speakers and OB's.

 

[Poultrygeist]

 

[Poultrygeist]

This is one way to mount them above the baffle but I've since used a single L bracket as well as a straight bracket.

 

[Poultrygeist]

The Neo 3 dipoles are so versatile they work well with box speakers. Great cymbal shimmer. They're so detailed and smooth that some over lap with the mains is fine in my book.

 

[Miron]

I've enjoyed a variety of tweeters over the years but the finest OB tweeter I've experienced so far is the Planar dipole B&G Neo 3 PDRw-2. B&G stands for Bohlender Graebener which went out of business for awhile when the owner passed away. I bought the two versions of the Neo 3 from PE shortly before they ceased production. Happy to report that B&G's are back in production and PE is carrying them again. They come with a back cover that makes them appropriate for box speakers. The cover is lightly glued on and should be removed to get the benefit of OB rear radiation. In the picture you can see how a blade is used to gently pry off the back cover. The round mount is extra and not necessary but it does allows for easy use with box speakers and OB's.

View attachment 1326969

Hello Poultry! What tweeters have you to your baffle with Zeniths?? Have you only a simple cap for tweeters??
If I put the same tweeters to my baffle without woofer is it good idea??
Thank you!!

 

[Poultrygeist]

Hello Poultry! What tweeters have you to your baffle with Zeniths?? Have you only a simple cap for tweeters??
If I put the same tweeters to my baffle without woofer is it good idea??
Thank you!![/QUOTE

With the Zeniths I use the Eminence ASD 1001 compression tweeters with wave guides paired with rear firing Realistic ( Radio Shack ) pod tweeters. Both tweeters use a 1.5uF cap on their + terminals and are driven from the same amp that powers the Zeniths. The Zeniths and tweeters cover the mids and highs but I like the Alpha woofers for the LF.

 

[Poultrygeist]

Hello Poultry! What tweeters have you to your baffle with Zeniths?? Have you only a simple cap for tweeters??
If I put the same tweeters to my baffle without woofer is it good idea??
Thank you!!

 

[Poultrygeist]

 

[djnagle]

Hey P, are you still using that horn? I use them in a pair of bookshelves and really like them.

 

[Poultrygeist]

Hey P, are you still using that horn? I use them in a pair of bookshelves and really like them.

Yes, they're excellent and don't cost an arm and leg.

 

[Miron]

View attachment 1327357

Thank you for your reply. I See that Eminence has a plastic at front that it has not it normally . What is this??

 

[Poultrygeist]

This is the waveguide I used. The ASD 1001 compression horn tweeter has a threaded end and the plastic waveguide just screws onto it. You have to purchase it separately.

https://www.parts-express.com/dayton-audio-h45e-45-x-45-elliptical-waveguide-1-3-8--18-tpi--270-314

 

[Poultrygeist]

You can see the threaded end on this ASD 1001 tweeter that accepts the waveguide.

 

[Miron]

You can see the threaded end on this ASD 1001 tweeter that accepts the waveguide.

Yes I understand. Of course Is this necessary for Eminence??

 

[Poultrygeist]

Yes I understand. Of course Is this necessary for Eminence??

Yes. With the Eminence the waveguide functions like the bell of a trumpet. Without it the sound would be thin and unable to project very far.

 

[Poultrygeist]

Zilla a friend at diyaudio uses the Eminence ASD 1001 in his OB's. Here's his blog which I'm sure I've already shared but this thread is too long to find or reference it.

https://speakerprojects.wordpress.com/2016/08/29/eminence-beta-12lta-on-open-baffle/

 

[Miron]

Zilla a friend at diyaudio uses the Eminence ASD 1001 in his OB's. Here's his blog which I'm sure I've already shared but this thread is too long to find or reference it.

https://speakerprojects.wordpress.com/2016/08/29/eminence-beta-12lta-on-open-baffle/

Thank you for your rich informations Poultry!!!
I have two questions for Zenith speaker:
1) Is this speaker capable for high volumes (loud)???
Because I see that when I play loud (no very loud),
I demote (lower) to the equalizer 500hertz, 1k , 2k, 4k
Generally I think that Zenith is not flat. If I add the woofer the problem will correct?? Perhaps my Zeniths have problem?? (I don't think because they are in perfect condition). I had other speakers Rogers etc. and I had not this problem at all volumes. But when I correct with my phone equalizer then Zeniths play magically. I love this sound , huge, elegant, with beautiful tone of magic. But I 'm confused and please I want help to solve this problem!!! And with the wood baffle and with the polystyrene baffle the problem is the same.( But the the wood had a lot of colourations).
2) What is preferred , to add the woofer firstly or the tweeters?? I have two pair of tweeters Zeniths, that I bought all these with the Zeniths 49cz852 . The one pair is 3inches and the other I think 1inch. I think that are no good in sound. I must to test these.
Sorry for the long text. I wait for your advises. Thank you again.

 

[Poultrygeist]

I listen mostly in the 70's and 80's and haven't tried high volume but I'm sure they'd play loud enough if pushed hard but their power band is limited.

OB's are not for headbangers and at 100 dbs you'll be hearing baffle vibration unless they're concrete. Folks go to great lengths to curb resonance with thick sand filled baffles or layers of composite held together with exotic sound absorbing green glues. Since I don't care for loud music I've always used basic 3/4 plywood or MDF. At the levels I listen at resonance is not audible.

The Zeniths are from the 1950's and were designed to be powered by flea watt tube amps. That was the only amplification available then. I doubt they would be a good match for a powerful solid state amp.

I would definitely go with the woofers first and power them separately from the Zeniths ( bi-amp ). The tweeters that came in my Zenith console were not very good and I trashed them.