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Open Baffle Epiphany!

z-adamson said:
I know what an h frame is, but what is an alpha h frame?
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The Eminence Alpha 15A is probably the most popular OB woofer sold today. It's got a whopping QTS of 1.26.

Eminence-Alpha-15A-Woofer-Driver.jpg
 
Poultrygeist said:
The Eminence Alpha 15A is probably the most popular OB woofer sold today. It's got a whopping QTS of 1.26.
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The question is....

What is an Alpha H frame?

I know what an H Frame is.

I have seen Eminence's catalog and as such I have seen the Eminence Alpha 15A in the catalog, along with everything else in there.

Am I to assume that an Alpha H Frame is an H Frame loaded with an Eminence Alpha 15A? But there are many Eminence speakers that are use the "Alpha" name.

Or is it an H Frame that is rather dominant in nature?
 
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z-adamson said:
The question is....

What is an Alpha H frame?

I know what an H Frame is.

I have seen Eminence's catalog and as such I have seen the Eminence Alpha 15A in the catalog, along with everything else in there.

Am I to assume that an Alpha H Frame is an H Frame loaded with an Eminence Alpha 15A? But there are many Eminence speakers that are use the "Alpha" name.

Or is it an H Frame that is rather dominant in nature?
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Yes it's the Eminence Alpha 15A and the reason it's so popular is that it's able to move more air in free space due to it's looser suspension. A low QTS woofer with a tight suspension needs a box so the air in the box can act like a spring. The Alphas are so common and have been around so long folks just call them by that name.
 
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Here are the high end Emerald Physics OBs which featured two Eminence Alpha 15A's and a Eminence Beta 12LTA. Other OB companies like Pure Audio and Hawthorne have used modified versions of the Alpha.

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For good OB bass you need a large woofer with high excursion ( cone travel ). Many woofers used in open baffles require EQ and one of the big advantages of the Alpha is it doesn't. That's a characteristic of purpose built OB woofers like the Lii Audio W-15 which I'd love to get my hands on.
 
fjdds said:
I see that the baffle cut on the these is smaller than the driver? Is this to create some sort of port, or focus the air movement from the Alpha 15As?
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Yes. I think it's similar to what is referred to as a SLOB or slot loaded open baffle. With a SLOB the woofers fire through a thin slot rather than a smaller hole.

5280a8c8612daf290e24ca94ec33b11d.jpg
 
opnly bafld said:
high end??? :dunno:
All budget speakers/models.

modified versions = the key, but still better drivers available

The original owner and designer of EP sold the company, now he is making better speakers. :thumbsup:
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The Emerald Physics shown above cost $4,795 back in 2011. Don't know if that included the active crossover which today would be over $500. Clayton Shaw started his new business with the tried and true Alpha 15A's.
 
It's quite common for speaker companies to start out with off the shelf drivers. Then with company growth they'll switch to proprietary speakers often made by Eminence which is largest speaker maker in the world. Proprietary speakers are often spruced up examples of the originals which might include things like cast frames and magnet cooling fins (?). The Eminence made Pure woofers are a good example of those. I've tested the Alpha against the far more expensive Hawthrone Augie and preferred the Alpha. The fact is the great majority of speaker companies don't make their drivers. They farm them out to companies like Eminence or Misco. Both Zu and Tekton use guitar based drivers made by Eminence. If you're ever near Eminence, Ky visit the Eminence plant for a nice tour.
 
opnly bafld said:
EP CS 2.3
"A good question to ask in all this is just how flawed hardware ingredients can be to ultimately not matter once digital corrections have 'fixed' them. Without digital EQ for example, Emerald Physics' raw speaker ingredients flatly wouldn't work, period." 6moons

Some newer models may have used the same cone and basket, but that doesn't mean it is a stock 15A.
All pictures I find have a different magnet, modified = not really a15A.

I don't see serious ($$$) diy'ers using Alpha 15s, just budget builds. The magnet is too weak (very high qts), it doesn't control the cone much (woolly bass).
People get used to something and think it is fine until they hear something better (some may just have bad hearing).
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Well I'm happy being a budget DIY guy. So what woofers do you use in your open baffles?
 
opnly bafld said:
A lot of people are and that is fine, doesn't mean what they have is what everyone should use and be happy with.
No longer use open baffle speakers, I have 2 stereo rooms and neither one is suitable.
Audiokinesis' LCS provides several open baffle like benefits, is much easier to integrate into more rooms, and is easy to diy (if Duke's fine speakers are out of budget).
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Didn't I read a few posts back that you were using the B200's in open baffles? That Visaton driver put OB's on the map. Unless your room is the size of a closet OB's are easier to integrate than box speakers. Actually I did try OB's in a closet and they weren't half bad. For someone who doesn't use OB's you sure spend a lot of time posting about them on every OB forum I visit.
 
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opnly bafld said:
You must have missed "were" (as in past) in the post about B200s. At one time I had 5 per side, one fullrange and 4 in parallel for bass only.
Sorry I don't do speakers in a closet, open baffle or boxed (IB and horn could work, but still not using a closet). :no:
I know you won't take my word for it, but speakers 5 to 6 feet out from the wall are not a good fit for my rooms. The speakers I have now do what I need them to do. :)
Ever try LCS?
In your world everyone that stops doing something (work, sports, hobbies) forgets all they have learned and/or are unwilling to share? :crazy:
Don't watch sports or you will be complaining about all the former players commenting on and analyzing the game. :eek:
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Wow, I'm impressed. You've had 10 B200's at $250 each in OB's at your young age. When I was a teenager I felt fortunate to have a transistor radio and I bagged lots of groceries after school. I've never spent anywhere close to $2500 on any build but maybe in my retirement years I'll save up enough to get to where you've already been. For years I've been keenly interested in a similar B200 project but you probably didn't take pictures so I won't ask.
 
opnly bafld said:
I bought 2 pair new (they weren't $250 ea then), the rest were used and I have been retired for 4 years.
Some people can see with their mind's eye, but I wouldn't expect you to have much in certain abilities.
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Since you're into those LCS speakers now and not using open baffles anymore would you be willing to sell the ten B200's? They won't work in your two listening rooms and I doubt you'll find another person interested in all ten. I thought you were very young as you didn't correct me in our last pm. You're just like my grandkids with all those many emoji's you use but now I stand corrected. We have a AK retirement forum here so I hope to see you posting there.
 
Alright fellas. This is ridiculous. I’ve read both of y’all’s posts for quite sometime now, and know that you both are very knowledgeable in this hobby. I respect both of you gents, and have learned from both of you. There is room enough for everyone’s opinion. This sparing match is getting pretty ugly.

Can we please pause, and take a breath. Let’s focus on positives, and stay away from the negatives. Shake hands, and let’s move on.

Best,

Geno
 
A new arrangement, de-commissioned the Zenith 1043's. They are crisp and detailed butfocal 5 inch1).JPG a tad forward for my tastes in character, so decided to try a smaller driver for better dispersion.
Had a couple Focal 5N313's, a pair I bought probably 35 years back. Nice cast frame, 5 inches with a rubber surround and a phase plug. Also bought a pair of
Goldwood GW-1248 12 inch woofers. They have a Qts. of 1. I rolled them off around 200 Hz. The Focal's drop off fairly steep below 100 Hz. and above 7-8K so they run full-range.
I have a small cloth dome tweeter to handle 6K+ on up with just a blocking capacitor.
The woofer is in a separate open backed enclosure from the one that houses the Focal and tweeter, also open backed. I did need to cut the Focal 3 dB to match
the woofer, but the sound is very balanced. The bass is fine without Eq. The screens keep kitty hands out of the mix.
 

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dfoulk said:
A new arrangement, de-commissioned the Zenith 1043's. They are crisp and detailed butView attachment 2687155 a tad forward for my tastes in character, so decided to try a smaller driver for better dispersion.
Had a couple Focal 5N313's, a pair I bought probably 35 years back. Nice cast frame, 5 inches with a rubber surround and a phase plug. Also bought a pair of
Goldwood GW-1248 12 inch woofers. They have a Qts. of 1. I rolled them off around 200 Hz. The Focal's drop off fairly steep below 100 Hz. and above 7-8K so they run full-range.
I have a small cloth dome tweeter to handle 6K+ on up with just a blocking capacitor.
The woofer is in a separate open backed enclosure from the one that houses the Focal and tweeter, also open backed. I did need to cut the Focal 3 dB to match
the woofer, but the sound is very balanced. The bass is fine without Eq. The screens keep kitty hands out of the mix.
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Very nice. What do the backs look like?
 
Poultrygeist said:
Very nice. What do the backs look like?
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Hi Poultry:)

Turned one around for a portrait. I also need a rear guard from kitties around here, but I have compared a shallow baffle with these and not noticed a terrible
downside to having the sides. I do like those Focal mids though, so glad that I tried them out for size. I guess that I had developed a bias for the larger drivers
over the years, but these 5 inchers are nice. I don't know when Focal stopped making them, but they are solid.
 

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