Open Baffle Epiphany!

[TubeHiFiNut]

I have the Tang Bands.

The four Eminence Alpha 15s have been shipped from PE and should be here soon.

Been discussing the actual build with my friend the cabinet maker. We are rounding up the wood next weekend.

Everything should be built and mounted within a week or two.

I already have the Crown for the woofer, the SET amps for the Tang Bands, the Dahlquist DQ-LP1 and an SAE Parametric (if needed).

My biggest speed bump right now is the 60+ hour work weeks that are really cutting into my fun time.

 

[BHamm]

Congrats, those look very nice, and I'm sure they sound awesome.

FINALLY!!!! Finished my Hybrid OB Bookshelfs!!!

 

[PR Audio]

Congrats, those look very nice, and I'm sure they sound awesome.

Thanks! Yes they do...Will fine tune tomorrow using the active x-over.

 

[TubeHiFiNut]

Thanks! Yes they do...Will fine tune tomorrow using the active x-over.

Very nicely done!

Which active crossover are you using?

 

[Poultrygeist]

I have the Tang Bands.

The four Eminence Alpha 15s have been shipped from PE and should be here soon.

Been discussing the actual build with my friend the cabinet maker. We are rounding up the wood next weekend.

Everything should be built and mounted within a week or two.

I already have the Crown for the woofer, the SET amps for the Tang Bands, the Dahlquist DQ-LP1 and an SAE Parametric (if needed).

My biggest speed bump right now is the 60+ hour work weeks that are really cutting into my fun time.

I used 3/4" MDF with my flat baffle Alphas/Lowthers which works fine for low to moderate listening levels. Since I rarely listen to anything other than small group jazz I have little need to crank it up. To avoid resonance for those who listen at high volume levels thicker or re-enforced baffles would make sense.

 

[PR Audio]

Very nicely done!

Which active crossover are you using?

It's not in front of me, so don't have the exact model, but it is a Behringer CX-XXXX 2-Way Stereo/3-Way Mono.


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[PastTechFan]

It's not in front of me, so don't have the exact model, but it is a Behringer CX-XXXX 2-Way Stereo/3-Way Mono.


Sent from my iPhone using Tapatalk

CX-2310 maybe? I picked up one of those at PG's suggestion for my OB's.

 

[TubeHiFiNut]

I used 3/4" MDF with my flat baffle Alphas/Lowthers which works fine for low to moderate listening levels. Since I rarely listen to anything other than small group jazz I have little need to crank it up. To avoid resonance for those who listen at high volume levels thicker or re-enforced baffles would make sense.

Thank you for bringing this up - been wondering about the baffle thickness.

I listen to pretty much everything from Rock to Blues to Jazz to Classical - at moderate to high volume.

What do you think would be the best path forward to prevent resonance?

1. 1" baffle?

2. A 'sandwich' of plywood on the outside and MDF in the middle? 1/2" or 3/4" for each of the 3 parts of the 'sandwich'?

3. Re-enforced baffle like the Jamo R909 (pic attached)?

4. Some other ideas?

Thank you for your ideas.....

 

[PR Audio]

CX-2310 maybe? I picked up one of those at PG's suggestion for my OB's.

Reading the manual right now...Yes, CX-2310, and, as in your case, PG is to blame!!!

 

[TubeHiFiNut]

Reading the manual right now...Yes, CX-2310, and, as in your case, PG is to blame!!!

That's who I blame for all this wonderful OB fun. :yes:

 

[Mister Pig]

Thank you for bringing this up - been wondering about the baffle thickness.

I listen to pretty much everything from Rock to Blues to Jazz to Classical - at moderate to high volume.

What do you think would be the best path forward to prevent resonance?

1. 1" baffle?

2. A 'sandwich' of plywood on the outside and MDF in the middle? 1/2" or 3/4" for each of the 3 parts of the 'sandwich'?

3. Re-enforced baffle like the Jamo R909 (pic attached)?

4. Some other ideas?

Thank you for your ideas.....

The OB I have hear use a hardwood front panel, and the drives are mounted to individual sections of MDF. The MDF/driver combination is bolted to the hardwood frame, but there is a layer of rope on the front side of the MDF to isolate it from the hardwood frame. The system seems to work well. But I have a 10" coax driver and the slight recess between the driver and front panel is not an issue. May not be true with other types of drivers.

Regards
Mister Pig

 

[TubeHiFiNut]

The OB I have hear use a hardwood front panel, and the drives are mounted to individual sections of MDF. The MDF/driver combination is bolted to the hardwood frame, but there is a layer of rope on the front side of the MDF to isolate it from the hardwood frame. The system seems to work well. But I have a 10" coax driver and the slight recess between the driver and front panel is not an issue. May not be true with other types of drivers.

Regards
Mister Pig

Thank you, Mister Pig.

May I impose on you to post a picture so I can better visualize how you put your OB together?

Thank you.

 

[Poultrygeist]

Thank you for bringing this up - been wondering about the baffle thickness.

I listen to pretty much everything from Rock to Blues to Jazz to Classical - at moderate to high volume.

What do you think would be the best path forward to prevent resonance?

1. 1" baffle?

2. A 'sandwich' of plywood on the outside and MDF in the middle? 1/2" or 3/4" for each of the 3 parts of the 'sandwich'?

3. Re-enforced baffle like the Jamo R909 (pic attached)?

4. Some other ideas?

Thank you for your ideas.....

My experience so far has only been with 3/4 ply or MDF.

Based on some threads I've read a sandwich of 1/2 inch materials with a layer of green glue between works well. Green glue has special acoustic deadening properties.

Some of the Hawthorne baffles are sand filled.

 

[TubeHiFiNut]

My experience so far has only been with 3/4 ply or MDF.

Based on some threads I've read a sandwich of 1/2 inch materials with a layer of green glue between works well. Green glue has special acoustic deadening properties.

Some of the Hawthorne baffles are sand filled.

Probably won't go with sand filled.

Sounds like a sandwich may be the way to go.

Thank you, PG.

 

[Porkloin]

Sandwich Suggestion

Probably won't go with sand filled.

Sounds like a sandwich may be the way to go.

Thank you, PG.

Mmmmm...sa-a-a-aandwich.....

 

[PR Audio]

That's who I blame for all this wonderful OB fun. :yes:

I can see the pattern of PG trying to conquer the world! One OB at a time!


Sent from my iPhone using Tapatalk

 

[Poultrygeist]

I can see the pattern of PG trying to conquer the world! One OB at a time!


Sent from my iPhone using Tapatalk

Fooling with OB's is a blast.

Maybe as much fun as you can have with your pants on.

 

[Mister Pig]

Thank you, Mister Pig.

May I impose on you to post a picture so I can better visualize how you put your OB together?

Thank you.

Here is a picture I happen to have. Still a bit hard to see but the back panel is bolted onto the front hardwood one. A caulking rope like what is used for sealing the door of a wood stove is sandwiched between the two woods. This is all standard practice on the Hawthorne speakers.

Oh I did not build these, as I am just a simple pig. Do not have these kind of woodworking skills.

Regards
Mister Pig

 

[TubeHiFiNut]

Here is a picture I happen to have. Still a bit hard to see but the back panel is bolted onto the front hardwood one. A caulking rope like what is used for sealing the door of a wood stove is sandwiched between the two woods. This is all standard practice on the Hawthorne speakers.

Oh I did not build these, as I am just a simple pig. Do not have these kind of woodworking skills.

Regards
Mister Pig

Thank you, Mister Pig. Apologies for the delayed response. Been quite the week at work.

Something tells me that you are an incredibly talented pig who knows his way around a Hi-Fi better than most.

On my new OB project front, my Eminance Alpha 15s arrived yesterday.

Time to get this OB build started.....! :yes:

 

[PR Audio]

Here is a picture I happen to have. Still a bit hard to see but the back panel is bolted onto the front hardwood one. A caulking rope like what is used for sealing the door of a wood stove is sandwiched between the two woods. This is all standard practice on the Hawthorne speakers.

Oh I did not build these, as I am just a simple pig. Do not have these kind of woodworking skills.

Regards
Mister Pig

I just started woodworking, but these are not difficult to replicate or get close to that. A router definitely would be needed, a miter saw would be nice to have, and obviously a circular saw (straight edge or table).

The front panel can be made of 1/2" thk veneered wood, cut in three equal squares (dims can be scaled from the driver size), the back panel to which the driver bolts is 1/2" painted wood or a composite panel, and there is a 1/2" thk x approx. 1" wide frame for edging the back of the front panels creating a recess for the rear panel holding the driver. The legs and rear supports look like 1" x 2" oak board cut at angles with a miter saw. A router would be used to round the edges of the front panel and create the top and bottom caps by grooving. Hardware is easy to find at a hardware store, as they are flat head 1/4-20 hex-drive connecting bolts or screws; if bolts a 1/4-20 x 5/8" brass expansion nut has to be inserted in the behind the front panel. As for the crossover, easy to build, and I would actually flip it upside down as to keep it concealed.

Sounds like a lot of work, but the most difficult part is using the router.

Thank you, Mister Pig. Apologies for the delayed response. Been quite the week at work.

Something tells me that you are an incredibly talented pig who knows his way around a Hi-Fi better than most.

On my new OB project front, my Eminance Alpha 15s arrived yesterday.

Time to get this OB build started.....! :yes:

Work always gets in the way...Good for you! Keep us updated as the build progresses.