What Should It Cost...?

[toddalin]

To make something like this in a similar finish, well braced, 3 feet tall to house an 18" and a 10"?

https://images.craigslist.org/00m0m_...I_1200x900.jpg

[Robh3606]

Hard to say?? Really depends on the materials chosen. Prices have gone up a lot since my last build just looking at MDF. Without cabinet size in Cu Ft it's hard to begin an estimate. I use precut 2'x4' 3/4" With half rounds front corners. So calculate the cabinet size to see how many sheets. As a starter plus double flared bass ports. 3" or 4" single or double??

Obviously going for a sub enclosure on the 10". You can use concrete tube forms for that so relatively cheap.

Have any idea what you want to use or are you contracting it out??

Rob

[toddalin]

Hard to say?? Really depends on the materials chosen. Prices have gone up a lot since my last build just looking at MDF. Without cabinet size in Cu Ft it's hard to begin an estimate. I use precut 2'x4' 3/4" With half rounds front corners. So calculate the cabinet size to see how many sheets. As a starter plus double flared bass ports. 3" or 4" single or double??

Obviously going for a sub enclosure on the 10". You can use concrete tube forms for that so relatively cheap.

Have any idea what you want to use or are you contracting it out??

Rob

Farmed out, as shown, but sized at 3' tall, ~22" wide, ~24" deep and to hold an 18" and 10" is ~$3,200, in furniture grade (as shown), audiophile grade (well braced) cabinets, with grills, similar to what you see in the picture. I could make mods at small cost.

[Robh3606]

Those will look nice with a Heil up top! I have never had cabinets built so I can't say if that number is typical or not. Might want to PM Widget.

Looking at it DIY say aprox 10 cubic ft. I would estimate roughly $600 in materials for the pair. Using $30 per sheet for MDF 4" doubled flared port. Are you going to port your 10 or go sealed?? The vernier cost is an open question depending on the cut, type and wood chosen.

That is using precut 1/4 sheets not full. So max width will be less than 24" to make sure you have square unblemished edges.

You going to put them on short stands?? Or casters??? They are going to be heavy!!

Rob

[toddalin]

Thanks.

Would probably use a small port for the 10" (piece of 1-1/2" PVC or such).

Hadn't thought about feet or wheels. Wheels would be easier, but that would be a lot of weight, so they would need to be quality..., maybe not Harbor Freight. Inevitably, one would sit partially on the bricks on the fireplace mantle and the other on a stand of similar height. Alternatively, if the wheels unplug, this could compensate for the height of the bricks for the one channel.

And there we have it! Casters that unplug, sized to the bricks so the rear casters could be removed with the front casters left in place for the one cabinet to be level with the bricks.

[Earl K]

Looks nice Todd.

Cost seems quite inline with my best guess.

What size sub-enclosure will the 2251j be working in?

[toddalin]

Looks nice Todd.

Cost seems quite inline with my best guess.

What size sub-enclosure will the 2251j be working in?

~0.75 cu ft. Existing cabinet is ~ 0.6 cu ft. and works fine.

An alternative would be to just build nice cabinets for the 18"s and use the existing 10" cabinets, which excel at imaging. I would be able to time align them and tilt them as I currently do. But I lose volume for the 18". The 10" cabinets are in satin black wood with rounded edges. I would kind of like to get away from the "PA" look of the 18"s and even treated with sound deadening liner material and acoustic foam (but no internal bracing), they ring at some frequencies and soak up others.

https://cimg0.ibsrv.net/gimg/www.cor...58107c6978.jpg

[rusty jefferson]

Farmed out, as shown, but sized at 3' tall, ~22" wide, ~24" deep and to hold an 18" and 10" is ~$3,200, in furniture grade (as shown), audiophile grade (well braced) cabinets, with grills, similar to what you see in the picture. I could make mods at small cost.

If someone would make you a pair of those same cabinets with faceted baffles (2" thick?), non-parallel sides, holes cut, veneered, finished, in your 3'x2'x2' size and appropriately built for the task including grilles for $3200, it's a bargain in my opinion. Jump on it.

[toddalin]

Looks nice Todd.

Cost seems quite inline with my best guess.

What size sub-enclosure will the 2251j be working in?

Actually, I've given this some thought and I think that maybe the best way, and certainly easiest, is to use a large, heavy, wooden "salad bowl" caulked to the inside of the main cabinet. This would be round with a concave or spherical inside bottom, which is reported to be the best shape to alleviate internal reflections and standing waves. It would also be easy to drill to run wires or even port, if it came to that.

Remember that the 2251J is made to be used in a small enclosure that is horn loaded. They essentually treat is as a large horn driver in it's intended purpose.

[toddalin]

I did up the cabinet in CAD and sent the drawings to the builder, but have not heard back. Maybe he figured that there was just no way he could do it at that kind of a cost. Or maybe he just needs some time. But no response doesn't instill much confidence when you would expect to initially lay out $$$ for materials.

The Heil sits on top with it's center at 3-1/2". The centers of the Heil and 2241H converge with the center of the 2251J at a distance of 130" (10'10") which is my listening distance. The sides of the 10" "fall away" so as to increase imaging. When the cabinet is on casters, the center of the 10" is at listening height sitting on my sofa.

The drawing does not show the porting or sub-enclosure for the 2251J. The squares represent square inches so you could actually figure the actual cabinet volume from the drawings, though you need to consider the volume of 18", the sub-enclosure, and bracing.

https://cimg4.ibsrv.net/gimg/www.cor...1202798bc3.jpg

[Robh3606]

Hello Toddalin

So you going for a focused array kind of like the larger Focals??? Are you going to have a sled for angle adjustment on the HEIL if you change listening distance changes or to experiment??

I am surprised you set the angle for the 2241 and not the 2251. Curious to see how this works I have never built that type of cabinet so I really don't know with no practical experience.

If you purchase the HEIL mounting kit you get a rubber block to aim the HEIL up at about 10 degrees of so. Makes sense with the directivity being so tight.

You are aiming the backwave up at the backwall so depending on what's behind them all the reflections may influence the imaging on the HEIL. When I had my HEILS up I attenuated the backwave. Probably from years of using monopoles. Just didn't sound right to me liked sharper imaging with attenuation but that's all about preference.

You are also a 3 way so the mids may "fix the image" as opposed to just a HEIL 2 way.

May also increase the sense of space?? Let us know.

Keep us posted!

Rob

[toddalin]

Hello Toddalin

So you going for a focused array kind of like the larger Focals??? Are you going to have a sled for angle adjustment on the HEIL if you change listening distance changes or to experiment??

I am surprised you set the angle for the 2241 and not the 2251. Curious to see how this works I have never built that type of cabinet so I really don't know with no practical experience.

If you purchase the HEIL mounting kit you get a rubber block to aim the HEIL up at about 10 degrees of so. Makes sense with the directivity being so tight.

You are aiming the backwave up at the backwall so depending on what's behind them all the reflections may influence the imaging on the HEIL. When I had my HEILS up I attenuated the backwave. Probably from years of using monopoles. Just didn't sound right to me liked sharper imaging with attenuation but that's all about preference.

You are also a 3 way so the mids may "fix the image" as opposed to just a HEIL 2 way.

May also increase the sense of space?? Let us know.

Keep us posted!

Rob

Thanks Rob, One at a time:

The Heils are mounted on smoked acrylic stands with the center of the slot at 3-1/2" above the mounting surface. These are from an AMT1D and do have the older rubber gaskets that were not angled. The angle of the top of the cabinet perfectly puts the center of the Heil to intersect the 2251 and 2241 at my listening spot, that has been my listening spot for the last 30 years, with no forseeable changes. If I do want to re-angle the Heil, I can simply place felt pads under the front/rear feet as I do now. But at 10'-10", placed 7-1/2' center to center, this is where the speakers throw a really nice soundstage/imaging, and even if I moved, this would be the approximate goal.

There is no backwave! This is blocked off and it's reflection is what makes the Heils work (image/soundstage) like you can't believe! I found the secret to making the Heils work with a ~flat response above ~3kHz and you can read about it on AudioKarma.

I run these as a 2.5-way.

This shows my mounts. The front diffuser has now been replaced by a rear reflector and the foam wedges have been replaced by "flares".



These are a regular CD played on an Oppo95 through a Yamaha RX-Z9 RECEIVER in "Pure Direct" mode. There is no eq, digital processing, or room correction, electronic or acoustic. You need good monitors to appreciate these.

Both L-pads are run "flat out" and could be removed entirely.


https://youtu.be/bMDzU5-z-Yw
https://youtu.be/WkgqMew8zRo

[Robh3606]

"There is no backwave! This is blocked off and it's reflection is what makes the Heils work (image/soundstage) like you can't believe! I found the secret to making the Heils work with a ~flat response above ~3kHz and you can read about it on AudioKarma."

Hello Toddalin

I am a little confused here. You say it's blocked of and it's reflection adds to soundstage??? Through the diaphragm???

When I was running my HEILs I ended up absorbing it with fibreglass batting. Made a huge difference imaging wise!

Rob

[toddalin]

"There is no backwave! This is blocked off and it's reflection is what makes the Heils work (image/soundstage) like you can't believe! I found the secret to making the Heils work with a ~flat response above ~3kHz and you can read about it on AudioKarma."

Hello Toddalin

I am a little confused here. You say it's blocked of and it's reflection adds to soundstage??? Through the diaphragm???

When I was running my HEILs I ended up absorbing it with fibreglass batting. Made a huge difference imaging wise!

Rob

I was initially doing that also and yes, it really helps soundstage and imaging. But I found a way to take it to a whole new level.

I was using the acousticmat and foam to block off the rear. But BION, the acousticmat was creating a reflection that was interfering with the diaphragm and creating a suck-out at ~6kHz IIRC. Removing the acousticmat but leaving the foam, the suck-out goes away. But the foam really doesn't do alot to block the rear wave, nor focus it back to the diaphragm in a constructive, rather than destructive, manner.

So, I came up with a convex strip that fits PERFECTLY into the Heil recess and focus the rear wave back to the diaphragm in a constructive manner. Of course, "THERE IS NO FREE LUNCH" and regardless of how the crossover is set up, there is a "brick wall" at ~3kHz with a "mesa" above that all the way past audibility. This REALLY brought out extreme detail in the recordings!

But, there was still improvement to be had. A piece of felt was placed over the convex strip, reducing the volume of the Heil by ~0.1-0.2 dB, but enhancing detail, imaging, and soundstage and this is how the recordings were made! If you follow the thread, you will see that the 4-6kHz is now just a bit higher than the 10kHz. The felt primarily reduces the 4-6kHz making it flat to the 10kHz and lets the Heil blend a bit better with the 2251 in the crossover area.

https://audiokarma.org/forums/index....-heil.1025205/

In the immortal words of The Firesign Theater, "And to think, all I had to do was to put the balls on the other side!"

When the "strip" is pushed in all of the way, it is a near perfect fit with it's flat back pretty much inline with the Heil's indent.

[hjames]

Interesting! Thank you for the rear shot of the Great Heil. In the previous picture it did look like the rear of the driver was blocked with accoustic foam.
Nice to get a clear image and description of what's going on back there.

I was initially doing that also and yes, it really helps soundstage and imaging. But I found a way to take it to a whole new level.

I was using the acousticmat and foam to block off the rear. But BION, the acousticmat was creating a reflection that was interfering with the diaphragm and creating a suck-out at ~6kHz IIRC. Removing the acousticmat but leaving the foam, the suck-out goes away. But the foam really doesn't do alot to block the rear wave, nor focus it back to the diaphragm in a constructive, rather than destructive, manner.

So, I came up with a convex strip that fits PERFECTLY into the Heil recess and focus the rear wave back to the diaphragm in a constructive manner. Of course, "THERE IS NO FREE LUNCH" and regardless of how the crossover is set up, there is a "brick wall" at ~3kHz with a "mesa" above that all the way past audibility. This REALLY brought out extreme detail in the recordings!

But, there was still improvement to be had. A piece of felt was placed over the convex strip, reducing the volume of the Heil by ~0.1-0.2 dB, but enhancing detail, imaging, and soundstage and this is how the recordings were made! If you follow the thread, you will see that the 4-6kHz is now just a bit higher than the 10kHz. The felt primarily reduces the 4-6kHz making it flat to the 10kHz and lets the Heil blend a bit better with the 2251 in the crossover area.

https://audiokarma.org/forums/index....-heil.1025205/

In the immortal words of The Firesign Theater, "And to think, all I had to do was to put the balls on the other side!"

When the "strip" is pushed in all of the way, it is a near perfect fit with it's flat back pretty much inline with the Heil's indent.