You said it X.
Way to go Squiffy, you are reflecting the same feelings I had on my first one.
Cheers.
That tracing wheel looks like a good idea. I wonder how it would work on the Sure-ply wood? I remember, about the only frustrating thing with these (I am a very impatient person) was poking those holes to get the pattern onto the wood. It looks like it would do a good job. I also think the indents it creates are actually a bonus for the gluing.
I've got some scrap ply in the garage, I'll give it a bash later and let you know.
I'll admit I'm not the world's most patient person either, hence why I experimented with the tracing wheel as I didn't fancy trying to mark it all out by hand. Plus I thought the rolling motion of the wheel might make it easier to mark out the curves.
If the paper surface had been absorbent or I'd been using depron foam, I saw a technique on the RC forums using acetone to transfer ink from printouts directly to the foam that looked like a very fast and accurate method of transferring templates.
Squiffy's build epitomizes the beauty of this speaker: you don't need no stinkin' T/S parameters! He just pulled out some drivers from a random computer speaker and popped them in. I find that it works with both low Qts and high Qts drivers - adjust the stuffing to taste and let the foam core flex do its job in taking out peakiness of the high Qts drivers.
Cal,
Attached is the result of running the tracing wheel over part of my template onto some birch ply. Not too bad, although you would probably have to trace over the marks. Not sure how long the tracing wheel teeth would last cutting in to ply either. But then they're relatively cheap to replace.
Attached is the result of running the tracing wheel over part of my template onto some birch ply. Not too bad, although you would probably have to trace over the marks. Not sure how long the tracing wheel teeth would last cutting in to ply either. But then they're relatively cheap to replace.
Attachments
The first one was finished up this morning and hung in place. Well when I say finished, the speaker is, the picture element has hit a snag that will take a bit of sorting but that is in hand. Oh and as I'd finished the first one I rattled on and completed the second this afternoon 
I couldn't leave the first one all on it's lonesome and I was gagging to hear the stereo effect that these produce.
The enthusiasm and support from Mr X and Cal for this project both for myself and the other guys trying it out had to be honoured. So both are up and have been playing for the later half of the afternoon and evening.
The wife has been decorating so to keep in the good books whilst I played and to give the boxes a good workout I was playing music that she would appreciate. First up was the latest album from James Blunt. I like it and it sounded pretty damn good through the one speaker hung up on the wall. The second was soon finished and hung up along side it's counterpart. Dina Carol was then stuck on and the sound was incredible. A sound stage that totally took over the room. Volume was checked out and no distortion whatsoever. The wife commented that it was like being in the clubs down London all over again. High praise indeed from she who just doesn't get the Hifi thing.
Still pandering to my loveliests choices, although this choice is also a bit of a fave of mine, UB40's greatest hits compilation followed This would check out the bass notes as well as seeing how well the horn sections would fare. I shouldn't have had any doubts as the performance was incredible. How the heck can a couple of cheap computer speakers stuck into a pile of packing material be turned into something that out performs my KEF's? This cannot be right but by me giddy Aunts knickers it is! These little old chuck-aways are throwing notes and sounds around producing a sound stage that I would expect to have to pay several high hundreds of pounds to produce.
Please don't get me wrong, any that have read my posts will know that I'm no way an audiophile but I like what I like and any improvement on that is always a good step taken. My feelings on these are that it's not a step in improvement but a leap and the sort of leap that you might take if you were in the Matrix film, one building to another type of leap
So once again thanks to the guys for the thread, the encouragement to give it a go and to DIY Audio for another project completed.
Ps pics and maybe a video will follow when I get peace and quiet in the house again
I couldn't leave the first one all on it's lonesome and I was gagging to hear the stereo effect that these produce. The enthusiasm and support from Mr X and Cal for this project both for myself and the other guys trying it out had to be honoured. So both are up and have been playing for the later half of the afternoon and evening.
The wife has been decorating so to keep in the good books whilst I played and to give the boxes a good workout I was playing music that she would appreciate. First up was the latest album from James Blunt. I like it and it sounded pretty damn good through the one speaker hung up on the wall. The second was soon finished and hung up along side it's counterpart. Dina Carol was then stuck on and the sound was incredible. A sound stage that totally took over the room. Volume was checked out and no distortion whatsoever. The wife commented that it was like being in the clubs down London all over again. High praise indeed from she who just doesn't get the Hifi thing.
Still pandering to my loveliests choices, although this choice is also a bit of a fave of mine, UB40's greatest hits compilation followed This would check out the bass notes as well as seeing how well the horn sections would fare. I shouldn't have had any doubts as the performance was incredible. How the heck can a couple of cheap computer speakers stuck into a pile of packing material be turned into something that out performs my KEF's? This cannot be right but by me giddy Aunts knickers it is! These little old chuck-aways are throwing notes and sounds around producing a sound stage that I would expect to have to pay several high hundreds of pounds to produce.
Please don't get me wrong, any that have read my posts will know that I'm no way an audiophile but I like what I like and any improvement on that is always a good step taken. My feelings on these are that it's not a step in improvement but a leap and the sort of leap that you might take if you were in the Matrix film, one building to another type of leap
So once again thanks to the guys for the thread, the encouragement to give it a go and to DIY Audio for another project completed.
Ps pics and maybe a video will follow when I get peace and quiet in the house again
Squiffy,
So happy that it all worked out for you! I know the feeling when the wife gives unsolicited praise! Imagine how they would sound off you put some real drivers in them. But then again, it may be that your computer speakers are actually pretty good drivers. Good drivers don't have to be expensive as my measurements of the Vifa TC9FD have shown. Please post pics when you get a chance.
Cheers,
X
So happy that it all worked out for you! I know the feeling when the wife gives unsolicited praise!
Imagine how they would sound off you put some real drivers in them. But then again, it may be that your computer speakers are actually pretty good drivers. Good drivers don't have to be expensive as my measurements of the Vifa TC9FD have shown. Please post pics when you get a chance. Cheers,
X
Not that hard, but with a fair amount of pressure and much harder than for the foamboard. Given the extra pressure and the tougher surface of the ply, I just got the impression that the tracing wheel might blunt a bit sooner than when used on softer material.
Having said that I'm sure it would make it through a few templates before giving up the ghost and the one I used only cost ~£2 so when you consider that cost against your time/patience marking out by hand it's certainly worth it.
Squiffy,
Thanks for showing us the details of the tweeter - I think this may really expand on the possibilities for the Cornu for many of us. We may even try bi-amping with a DSP XO
X
I meant to say that the tweeter has a tiny little pot on the side however the original speakers had an internal power supply with tone balance and volume controls. I thought it might be a little too much to try and fit all of that in the box.
So how are you connecting the tweeter - fullrange direct drive to the main driver or with a high pass capacitor?
Btw, now that you don't have computer speakers anymore since you turned those into the cornu, you may be interested in these: http://www.diyaudio.com/forums/full-range/223313-foam-core-board-speaker-enclosures-226.html#post3847794
Btw, now that you don't have computer speakers anymore since you turned those into the cornu, you may be interested in these: http://www.diyaudio.com/forums/full-range/223313-foam-core-board-speaker-enclosures-226.html#post3847794
Ah and one other thing I should mention and this is by way of a word of warning to all you dining table builders (Cal, X I mean you guys) when glueing the back panel and loading it up with whatever heavy things you can find to weigh it down, in my case a cast iron casserole dish eight heavy dinner place mats, a box of all the goodies and tools used in the construction of said speakers and two vintage cast iron flat irons (the wife's kitchen ornaments shh don't mention that) it is advisable to have something to lay the speaker front on especially when the screws holding the drivers in place stick out just a little bit. And you definitely do not want to turn the speaker, in a turntable display type of way, to check if all the channels are glueing down nicely when you have all that weight on.
It has been a lovely sunny day over here in England, just the sort of day to spend outside sanding down an oak dining table to get rid of some nasty looking scratches and then giving it a liberal coating of teak oil. Hmmmmm teak oil.......
It has been a lovely sunny day over here in England, just the sort of day to spend outside sanding down an oak dining table to get rid of some nasty looking scratches and then giving it a liberal coating of teak oil. Hmmmmm teak oil.......
I kept it the same as they came out of the computer speakers, two leads direct to the two terminals on the main drivers. Is this the full range that you refer to?