Pictures of my Tri-amped Open Baffles

[Mash]

Well, Feanor... that Linkwitz Orion looks complicated..... Monopole tweeters, dipole mid and a series woofer? The Legacy Whisper I encountered some time ago but I remember nothing about them. But they look very complicated...... maybe too much so.... a violation of KISS.

These are both far beyond Pg 's DIY project, and they seem hardly appropiate as anyone's DIY projects.

[E-Stat]

Linkwitz "must" use complex crossovers which is thankfully avoided with multi-amped ...

It is an eight channel active design. Now using an H-frame for the woofers.

I'm sure sound fantastic with your gorilla amps...

You have no idea. And none of it is mine. That system recalibrated my notion of what an audio system can do many years ago. Sense of authority. Walls disappear. Spooky.

...but I see nothing relative to crossover-less full range drivers in OB.

You seem to think open baffle is a single design concept. That's like saying all electrostats are designed the same way. Some are hybrids. Some use frequency specific panels to achieve full range. Others use single panels or multiple identical panels. Not all are dipoles.

Vive la difference!

[E-Stat]

that Linkwitz Orion looks complicated..... Monopole tweeters, dipole mid and a series woofer?

Full range dipole on latter versions with the additional tweeter in rear. Dipole woofers driven with separate amps.

... they seem hardly appropiate as anyone's DIY projects.

You can buy the package as a kit here.. Including the active crossover with 44(!) op amps.

[Poultrygeist]

E-Stat, you seem so knowledgeable of DIY builds I'm anxious to see and read about yours. And please post some pictures.

[E-Stat]

E-Stat, you seem so knowledgeable of DIY builds. I'm anxious to see and read about yours. And please post some pictures.

Aware of many designs, yes. My DIY projects are now limited to room treatments and attenuators for the digital front end in the main system. There is no way to DIY a U-1. The last electronics I built were Dynakits when I was a teenager.

SE-2 (link to details)





The twelve bass traps used this recipe.



I'm still using the original owner's Kenwood receiver to drive speakers throughout the house and to the outdoor patio / pool with access to the digital library on my server along with internet radio of various sorts. It's nice having music indoors and out.

[Poultrygeist]

Any basic speakers?

[E-Stat]

Any basic speakers?

No,. Just rebuilt parts of the Advents. New wiring, crossover caps, felt tweeter diffraction.

I bid on a pair of Acoustat 1+1s on ebay, but they guy had too high a reserve. That's what I'd really like to replace the Advents in the garage.

[BoJonJovi]

The TB's look good and reviewed highly over many builds. They are out until September. Just nosing around I ran into the Goldwood GW-8003/8 8" Full Range Driver w/Whizzer for 26 bucks. What are your thoughts on the Goldwood GW-8003's?
I thought they might offer an ultra cheap introduction to OB while the TB come.

[Poultrygeist]

The Goldwoods look good but at 87 dbs will need power. I have a pair of these GRS below which are even cheaper and more efficient at 91dbs. They replaced the famous Pioneer BOFU full ranger that was a Nelson Pass favorite. I have a pair of those as well.


GRS 8FR-8 Full-Range 8" Speaker Pioneer Type B20FU20-51FW 292-430

[BoJonJovi]

The Goldwoods look good but at 87 dbs will need power. I have a pair of these GRS below which are even cheaper and more efficient at 91dbs. They replaced the famous Pioneer BOFU full ranger that was a Nelson Pass favorite. I have a pair of those as well.


GRS 8FR-8 Full-Range 8" Speaker Pioneer Type B20FU20-51FW 292-430

Glad you mentioned those. I was considered them as well. I think they can be had for around 14. I think I saw the qts of .40 vs .79 for the Goldwell and figured the Goldwell might be the better option.

[Poultrygeist]

Here's a link to an interesting enclosure using the Bofu ( GRS drop in ) but the GRS should work fine in OB. A qts of .40 is not bad for OB if you're using bass support ( H-frames ). The TBs are right at ,40

Pass The Bofu Building a transmission line cabinet for the Pioneer 8-inch full range driver. Article By Jeff Poth

[BoJonJovi]

Just curious. What do you think of the Tang Band W8-1772 for OB? I got one off ebay for $116 with the option to return it. I thought it might also make a cheap pair of voight pipes. Unfortunately PE will not have them in stock until August for me to finish the pair.

[Poultrygeist]

The wife has not been a happy camper with my large OB's. I brought this old single bed down from the attic and converted it into a garden bench. I cut the foot board into and used it for side arms. With the brownie points earned I can build more speakers in peace.

[BoJonJovi]

It looks lonely without a Gazebo. Hmm..., a gazebo would keep an amp out of the weather, and a pair of OA (Open Air) yard speakers disguised as yard art. You are brilliant.

[Poultrygeist]

I almost did a gazebo but instead did a screened porch where strange full rangers propagate.

The 1772 will work in OB as long as you augment the bass with H-frames.

[BoJonJovi]

Nice. Like the wine as well. Brewing wines and ciders is one of my other avocations. I have 60 gallons of various brews going. I guess a lifetime of working with at-risk kids, the mentally ill, and big bureaucracies makes one want to blunt the memories by indulging the other senses.

[Poultrygeist]

Between the two Tang Bands and the Beta, I think I'd go with the Beta. Reasons: cheaper, more efficient ( by 4dbs ) and much larger sound stage. A friend who has heard the TB's and Betas in my home wants me to build him these same Betas over H-frames. I trust his ear and as a professional violinist it feeds his family. He has owned Omegas, Tektons and Zu's but is enthralled with the Betas.

[BoJonJovi]

OK I am ready to pull the pin on the 12inch Beta.
Was there a reason for the alpha over the 15 inch beta for H frame woofers?
Seems like I might have read somewhere that there was a reason.

[Poultrygeist]

The 15 inch Alphas are just a better choice for H-frames. They have very high Qts and will move more air in open baffle. Even though the Alphas are efficient they'll still need 50 to 100 watts of solid state power. Actually they can handle even more if it's available. The Betas OTOH need only a couple of watts and preferably tube watts or t-amps watts.

If you build this you'll eventually end up driving the Betas with a SET. The $200 Miniwatt/APPJ on ebay is a great choice if you're on a tight budget. SETs and high efficiency full range drivers are a match made in heaven.

[Poultrygeist]

BoJon,

FWIW I too worked with at-risk kids for much of my career. My first job out of grad school was in a mental health hospital. I recently retired from a state agency serving children with SED/BD.

[BoJonJovi]

I started in public education working in lower economic class schools and alternative schools as a Special Ed teacher for Emotionally Behavior Disorder Kids.Then as school principals in schools that needed help to clean up problems. I retired from the Colorado Mental Health Institute as the Director of Patient Education. I really enjoyed the patients and kids in all settings but the bureaucracies were soul sucking; not too much PTSD but some.

Not on a real tight budget if I drag it out. I would like to build a SET as I get a little more experience.


I am going to go ahead and order the 15 inch alphas and the 12 betas. I thought about the cheaper full rangers but then I thought the 12 inch betas were not really budget breakers. I think I can still manage to keep the water and lights on and the wife should not beat me too bad.

[Poultrygeist]

The Betas over H-frame Alphas are good enough to be a final destination system.

Unless you use the Dayton APA150 amps with built in crossover controls you'll need to buy two 8 ohm 80hz low pass crossovers from Parts Express. I believe they cost $17 each. To save money on shipping and use their online discount coupon it's good to order everything from PE at the same time.

What amps will you be using?

[BoJonJovi]

I have the Class-D Audio 250x2. I am building the other Sure amp 250x2. It is about ready to go but I think I have something amiss with the polarity. I have not had time to fiddle with it. So I am thinking one amp for the top end and one for the bottom end. I am also thinking of the Dayton 150 in the future but cannot do it all at so I should probably get the low pass crossovers.
I am also thinking I need some tweeters. I was looking at the planer and ribbon tweeters from parts express but kinda have a jones for a horn as well. Any suggestions for tweeters? I will also need some caps for them.

[Poultrygeist]

If you drive them with their own amp you can use 4 ohm tweets with lower efficiency but if you run them off the same amp as the Betas I'd stick with 8 ohms and slightly higher efficiency than the Beta's 98dbs.

My 108 dbs 8 ohm super tweets were a PE buyout and no longer available.

I would consider: Eminence ASD1001 horn driver ( 8 ohm 103 dbs ) @ $29 each plus Dayton H45E wave guides @ $6.35 each or perhaps the Pioneer AHE60-51F @ only $12.32 each ( very good reviews but looks a little cheap - 100 dbs )

I have had good luck with these vintage Realistics ( see link below ) but they're only available on ebay and at flea markets. They are said to be the same as the highly regarded Fostexs. You can remove them from their pods and easily flat mount them in baffles. You can often find them for around $40 a pair.

Radio Shack 40-1310 Super Tweeter

[BoJonJovi]

After spending the moring reviewing tweets I am leaning toward the ASD 1001 with Dayton Waveguides.
However the Foster 025N03 Cast Aluminum Horn Tweeter caught my eye for a second and perhaps cheaper build.

Is there a reason you went with the 15" H-frame rather than the Goldwood-1858 H_frame?