have started painting
im thinking going gloss black on the stands and feet and sand and clear the balls
thoughts
im thinking going gloss black on the stands and feet and sand and clear the balls
thoughts
I love this idea.
Just finished reading the 33 pages now, and this one idea, from page 1 stuck with me.
Mounting the ball on pilotis over a cylinder housing a sub driver for 360 bass.
Bass driver would handle up to 100-150ish Hz, fullrange in the ball.
Made a crude model in Sketchup (I used to be fluent with FormZ in the old days, I do not like Sketchup at all!)
Just finished reading the 33 pages now, and this one idea, from page 1 stuck with me.
Mounting the ball on pilotis over a cylinder housing a sub driver for 360 bass.
Bass driver would handle up to 100-150ish Hz, fullrange in the ball.
Made a crude model in Sketchup (I used to be fluent with FormZ in the old days, I do not like Sketchup at all!)
Attachments
Goodlagger, it looks like you have a band wrapped around at the union of the two bowls. If so can you explain how you did this. I am searching for ways to professionally hide the joint, I thought maybe an aluminum band similar to your solution.
David
David
I haven't started my project yet, but I am thinking of using a solid 1" hardwood to space & join the 2 bowls. My challenge is to construct an auxiliary fence for my band saw to safely slice off the bottom of the bowl and create the platform to mount my woofer! I believe the wood insert would be 2 fold: first it will give me the needed space restoring the symmetrical, spherical shape. Second, it will give much needed space; allowing a deeper bass and acting as a ridged brace as well! The spacer/brace, will be perorated for good air transfer and acoustic damping. Given the proper stuffing!
no band was used sorry
all i did was sand the edge with a rough grit to allow for extra bondage lined up the grain and compressed together using weights i cut the hole for the woofer first and glued the ring in for the recess
any amp ideas guys ??????
all i did was sand the edge with a rough grit to allow for extra bondage lined up the grain and compressed together using weights i cut the hole for the woofer first and glued the ring in for the recess
any amp ideas guys ??????
It would appear that the large wooden Ikea Blanda bowls, as used with the initial builds, are no longer available. There is a similar large version, made of bamboo (should be fine, but less attractive imo), though it doesn't seem to be available here in the UK (maybe just for the US market?).
Shame, I was going to stash some for a future build with Jordan units.
Shame, I was going to stash some for a future build with Jordan units.
My original ones (pics on page 1), which have been gathering dust for a while now, took a tumble off the workbench and the magnet ripped from the driver. I don't want to fix them and it renders one useless.
So, they are up for grabs, free to a good home and anyone who wants to collect. Central Bristol
So, they are up for grabs, free to a good home and anyone who wants to collect. Central Bristol
Hi Goodlagger,
Looking good!
I'm honered 😀
Mean while I'm "working" on a new design to use the Blanda bowl speakers as a FAST system. I am going to incoparate two Pearless XLS-10 subs. I will be using two Hypex AS2.100 plate amps with DSP. So the stands will be replaced but they won't go to waste, they be used later on for the rearspeakers. The Blanda bowls with the Alpair drivers were ment to be used as rearspeakers from the start. But in combination with the AS2.100 modules they out performed my Dali 2.8 speakers by far so I started using them as front speakers.
Gooluck woth your build Goodlagger, I'm looking forward to the final result.
Dave, I'll shortly be inheriting Louis' Blanda bowls and I plan to rework them to use MA Alpair 7 drive units. I like your Onken approach; is there a possibility of getting hold of your CAD drawing that you included with the above post. I'm assuming you've dimensioned the ports correctly and there seems little point in re-inventing the (wagon)wheel.
Cheers
Ray
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Apologies for another (increasingly frequent!) senior moment. It seems that the 28cm bamboo version of the Blanda is available in the UK.
Also, having read through the full thread now I plan to use MA Alpair 7 drive units rather than the jordans.
Ray
Ray,
The plans were never really finished, but if you email i can send them to you. The venting for the A7 is different than the CHR, so vents would need changing. The A7 also has a larger bezel, so the driver rebate would need reworking.
dave
Here's why I asked....
An externally hosted image should be here but it was not working when we last tested it.
Had to take some rubbish to the local tip this morning and came back with these; cost me all of £2! My thinking is to use them as moulds to make something like papier mache backs to blanda front hemispheres. They're actually old light shades, made of aluminium, but with one or two little dents but they should be fine as moulds. Diameter is a 25.5cm (10in), which I think is very close to the inside diameter of the 28cm blanda bowl.
I'll try to measure the volume later. The volume will obviously be more than the Blanda hemisphere and perhaps sufficiently more to move up to an Alpair 10?
Ray
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Volume is 6 litres. A half Blanda is 4.5 litres so that's 10.5 litres, minus anything lost with mounting the driver plus any joining band, so lets assume a working volume of circa 10-11 litres total, which is getting into Alpair 10 territory I think (from calculating the volume of a vented design for that unit on the MarkAudio website).
I am of course assuming that the Alpair 10 is preferable to the Alpair 7.
Ray
I am of course assuming that the Alpair 10 is preferable to the Alpair 7.
Ray
An assumption, which depending on thedesired traits, is not so. The larger bezel, i would guess, wouldmean slicing off more of the sphere toallow it to fit,meaning less volume.
9-10 litre is p[timum for A7, 16-18 litre for A10p, 13-14 for A10.3
dave
Thanks Dave.
Assumption was based on anticipating a little more bass from the 10. I had considered the volume loss resulting from the larger chassis but had assumed this would be more than offset by the volume of a joining ring but I don't think that arrangement would give the volume required for optimal use based on your numbers - Alpair 7 it is then!
Any thoughts on my idea of moulding papier mache cones from the lamp shades for the rear sections? I've assumed papier mache as it would be easy to build up the required wall thickness to blend with the bowls. Plus it's cheap and easy. Have also considered plaster of paris impregnated bandaging to mould them - I think this would be superior but maybe a bit fragile and heavy.
Also, with a reflex arrangement, an obvious aesthetic location for the port would be the apex of the rear cone but that would then align it with the rear of the drive unit; any issues from an audio engineering perspective with that?
Still interested in considering your annular Onken approach - did you get my mail?
Ray
Assumption was based on anticipating a little more bass from the 10. I had considered the volume loss resulting from the larger chassis but had assumed this would be more than offset by the volume of a joining ring but I don't think that arrangement would give the volume required for optimal use based on your numbers - Alpair 7 it is then!
Any thoughts on my idea of moulding papier mache cones from the lamp shades for the rear sections? I've assumed papier mache as it would be easy to build up the required wall thickness to blend with the bowls. Plus it's cheap and easy. Have also considered plaster of paris impregnated bandaging to mould them - I think this would be superior but maybe a bit fragile and heavy.
Also, with a reflex arrangement, an obvious aesthetic location for the port would be the apex of the rear cone but that would then align it with the rear of the drive unit; any issues from an audio engineering perspective with that?
Still interested in considering your annular Onken approach - did you get my mail?
Ray