Hi, guys. *S* Both V2s' work, happy to report. Image nicely, but undergoing break-in for awhile before I give them a 'push'. The tweets may be a fail, as they don't seem to be holding up their end well at this point. But they are a straight up experiment; I can swap them out if desired.
Yep, they look odd, and those are foil tweets. *L* I 'repurposed' the bases from the original pair, but the 'new' drivers' baskets were slightly smaller so a lexan plate fills the difference between the hardware locations' different diameters. The drivers themselves have a 30w rms rating, so hopefully I won't 'cook' them as quickly. The rating of the V1 pair was unknown...
The tweets are using the 'heavier' of the 2 foils Cochleus donated for this endeavour (Thanks Again *G*). Might be too much mass, so I may make another pair using the lighter foil. They look particularly strange with the soda straw in the middle, a support for experiments in edge damping.
I'll have a better grasp of the tweets' situation after break-in when I'll hook it up to the mains and throw some serious eq at them. Make 'em sound funny for awhile, always good for at least a laugh...
With this pair I've tried for an improved 'build' and paid more attention to damping. Initial result seems that they seem more 'polite', lacking some of the 'attack' of the originals. The damping is removable, so I will see what removing it does later.
Break-in is fairly simple. Feed it a cd, set it to replay, and leave the area. When I've walked in on every segment of the cd at random, it'll either be done or I'll change the cd....
Yep, they look odd, and those are foil tweets. *L* I 'repurposed' the bases from the original pair, but the 'new' drivers' baskets were slightly smaller so a lexan plate fills the difference between the hardware locations' different diameters. The drivers themselves have a 30w rms rating, so hopefully I won't 'cook' them as quickly. The rating of the V1 pair was unknown...
The tweets are using the 'heavier' of the 2 foils Cochleus donated for this endeavour (Thanks Again *G*). Might be too much mass, so I may make another pair using the lighter foil. They look particularly strange with the soda straw in the middle, a support for experiments in edge damping.
I'll have a better grasp of the tweets' situation after break-in when I'll hook it up to the mains and throw some serious eq at them. Make 'em sound funny for awhile, always good for at least a laugh...
With this pair I've tried for an improved 'build' and paid more attention to damping. Initial result seems that they seem more 'polite', lacking some of the 'attack' of the originals. The damping is removable, so I will see what removing it does later.
Break-in is fairly simple. Feed it a cd, set it to replay, and leave the area. When I've walked in on every segment of the cd at random, it'll either be done or I'll change the cd....
Hi Jerry,
You are right about foil thickness effecting the amount of energy transfer to the cone. The .002" foil generally works good. The thin .001" foil sounded better to my ears, but is so much more difficult to work with, and is less mechanically robust.
The aluminum foil you are using is the same exact foil that Lincoln Walsh used for his prototypes (.002" full hardness). The cone area makes a big difference, the smaller cone is radiating a smaller amount of sound energy. But, I suspect you may be over damping or constraining the cone movement. What do you think?
Right now I suspect I may have too much cone for too small a driver; you can see from the pic that the driver is a dink. *L* I removed the damping to no discernible effect; I'm thinking about disconnecting them and running them 'bi-amped' so I can give 'em a harder 'push'. I can do this on the 'car stereo test rig' by just running them as the 'rears' and using the fader for level control. We'll see what gives with that...fly 'em or fry 'em. *G*
Again, nothing precious about them...
Again, nothing precious about them...
I am working on a walsh clone too.
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This is a 38mm voicecoil,from a 5.5" unit from seas.
[/url][/IMG]
[/url][/IMG]
Here cones .One made from 15my alu and 12my mylar.The other from alu/mylar film and 50my adhesive alutape.
No sound yet.Both are corugated to increace stifnes.
Bernt
This is a 38mm voicecoil,from a 5.5" unit from seas.
Here cones .One made from 15my alu and 12my mylar.The other from alu/mylar film and 50my adhesive alutape.
No sound yet.Both are corugated to increace stifnes.
Bernt
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Nice work, Bernt. I particularly like the slenderness of your standoffs...beats my clunky ones on esthetics...
What are you using for a surround at the base of the cone? It looks to me like you're adhering to the cone and segmenting to the basket, which is valid and will work but seems labor intensive... Centering and not distorting the cone base could be an issue? Just saying...your workbench and I'm just kibitzing....*G*
But I agree with Cochleus..."Whats' it Sound Like?" *L* When you get to it...
(I should talk...I'm out of town on a project until the weekend, so my progeny sits silent, un-messed with...*sigh*)
What are you using for a surround at the base of the cone? It looks to me like you're adhering to the cone and segmenting to the basket, which is valid and will work but seems labor intensive... Centering and not distorting the cone base could be an issue? Just saying...your workbench and I'm just kibitzing....*G*
But I agree with Cochleus..."Whats' it Sound Like?" *L* When you get to it...
(I should talk...I'm out of town on a project until the weekend, so my progeny sits silent, un-messed with...*sigh*)
An update moment:
Walsh style tweeters on 2A & B units are a 'fail'; cones have been salvaged and are looking for a new, more robust driver pair to be mated to.
I've noticed that the voice coils for the main cone drivers can generate a considerable amount of heat. If you touch the stems that previously supported the tweeters after being driven hard, they get quite hot. No surprise there; since the coils are being constrained driving the cone in a totally different fashion, selection of a driver with a voice coil rated for high temperatures/wattage becomes a must. That, and more attention to the t/s parameters if opting for modifying a new driver...
On a 'listening impressions' note, the 2A & B like to be about 4' from the back wall. Imagining is enhanced when you do, and they still love pianos. Thinking about mating them with a small ribbon tweeter, as the 'high end' rolls off to my ears. I really need to wave a calibrated mike at them to verify this terribly subjective impression...
Attached is a pic of the bases for 3A~3D, with one of the 4 drivers in the foreground. Still a ways to go before they can make some noise, but getting these assemblies to this state has been a major step that can now be marked off the 'to do' list. We shall see if 'bigger is better' soon enough...
Walsh style tweeters on 2A & B units are a 'fail'; cones have been salvaged and are looking for a new, more robust driver pair to be mated to.
I've noticed that the voice coils for the main cone drivers can generate a considerable amount of heat. If you touch the stems that previously supported the tweeters after being driven hard, they get quite hot. No surprise there; since the coils are being constrained driving the cone in a totally different fashion, selection of a driver with a voice coil rated for high temperatures/wattage becomes a must. That, and more attention to the t/s parameters if opting for modifying a new driver...
On a 'listening impressions' note, the 2A & B like to be about 4' from the back wall. Imagining is enhanced when you do, and they still love pianos. Thinking about mating them with a small ribbon tweeter, as the 'high end' rolls off to my ears. I really need to wave a calibrated mike at them to verify this terribly subjective impression...
Attached is a pic of the bases for 3A~3D, with one of the 4 drivers in the foreground. Still a ways to go before they can make some noise, but getting these assemblies to this state has been a major step that can now be marked off the 'to do' list. We shall see if 'bigger is better' soon enough...
Attachments
Here my latest creation:
[url=http://www.diyaudio.com/forums/gallery/showphoto.php/photo/11980]
[/URL]
This one uses a rubber surround and the cone is made from 50my selfadhesive tape and 15/12my foil.
The first one was 15/12 my foil and a surround made from 3M microporre tape.
The treble is too weak in both models.
I think the best material for the cone is stiff and light.Hardened alu or titanium.
Maybe we should use a dustcap to cool the coil better.
Bernt
[url=http://www.diyaudio.com/forums/gallery/showphoto.php/photo/11980]
[/URL]This one uses a rubber surround and the cone is made from 50my selfadhesive tape and 15/12my foil.
The first one was 15/12 my foil and a surround made from 3M microporre tape.
The treble is too weak in both models.
I think the best material for the cone is stiff and light.Hardened alu or titanium.
Maybe we should use a dustcap to cool the coil better.
Bernt
Merry Post-Xmas, Båndsei... *G*
Treble is a bit 'thin' on mine as well, which is why I've attaching various tweeters on top, as well as trying to create a version of my own (ergo the 'ice cream cones' that didn't work).
Titanium is one material that German Physiks uses on their units, as well as carbon fibre. Still a bit 'rich' for my budget, which is near to nil as I can make it. *L* Something to work towards.... I'm still using 5 mil litho aluminum, as I've got Lots of it...
How tall is your unit in the pic? It seems large/tall, nothing to scale it by in the frame...
As for the heat, I've just stayed conservative with the volume. One response is to use a driver rated for higher wattage, but I suspect that the load placed on the voice coil driving a restrained cone takes its' toll eventually. Voice coils with ferrofluid might help; it's been suggested to me to mind the t/s parameters...the specific one escapes my midget mind this moment, but I'll look back and post it here later...
Is that a salad bowl base? *G* Nicer than PVC...
Treble is a bit 'thin' on mine as well, which is why I've attaching various tweeters on top, as well as trying to create a version of my own (ergo the 'ice cream cones' that didn't work).
Titanium is one material that German Physiks uses on their units, as well as carbon fibre. Still a bit 'rich' for my budget, which is near to nil as I can make it. *L* Something to work towards.... I'm still using 5 mil litho aluminum, as I've got Lots of it...
How tall is your unit in the pic? It seems large/tall, nothing to scale it by in the frame...
As for the heat, I've just stayed conservative with the volume. One response is to use a driver rated for higher wattage, but I suspect that the load placed on the voice coil driving a restrained cone takes its' toll eventually. Voice coils with ferrofluid might help; it's been suggested to me to mind the t/s parameters...the specific one escapes my midget mind this moment, but I'll look back and post it here later...
Is that a salad bowl base? *G* Nicer than PVC...
Oh, that's way cool! I've been to Linkwitzs' site too...it's nice that a legend is a fan of PVC. *G* Glad to see someone else has a nest of cable snakes....
The angle seems to vary depending upon whose building it, IMHO. The patent shows both squat and narrow, so it may vary +/-15 degrees from my best 'guesstimate'. It'd probably make for an interesting trial to see if and how it might effect response...
More bowls, or are you a wood turner?
The angle seems to vary depending upon whose building it, IMHO. The patent shows both squat and narrow, so it may vary +/-15 degrees from my best 'guesstimate'. It'd probably make for an interesting trial to see if and how it might effect response...
More bowls, or are you a wood turner?
Serious listening hour
OK, break-in continues...3 of the 4 sound very similar to each other to my ears, which is pleasing. The 4th has a 'roughness' that occurs with various frequency/peak combinations. A suspected voice coil misalignment which, considering how 'high tech' the construction/assemble routine I've managed, isn't a huge surprise....
The 'high tech' cure? A piece of steel wire with a piece of aquarium tubing, hooked to the basket frame, up against the cone/voice coil intersection. A forced re-alignment...
Real 'hacksaw & hammer tech'. The KISS response. Beats the F out of a rebuild....
Meanwhile....
Larger cones=deeper bass response, no surprise there.
They can play louder=bigger radiation surface, ditto.
4 instead of 2=there IS a 'sweet spot' in the center. Depending upon the 'mix', a snare drum can appear right in front of you. A vocalist next to you. A guitar is over there, but Moves. A 'sound soup' that moves around you. It'd be a hoot to set them up in a totally empty room and see what happens. Play with knocking the 'back' pair out of phase with the front pair and see what interference patterns occur....
I'm considering pairing them, base to base, with a short sleeve, a routine I discussed with Magnasanti some pages back. I suspect the 'normal' dispersion of a walsh will return, but I'm curious to hear what having the cones 'push' against each other would do. Will they interfere with each other, exhibit cancellations, damp each other? Something unforeseen?
*S* It's fun to have my new 'toys' work.
OK, break-in continues...3 of the 4 sound very similar to each other to my ears, which is pleasing. The 4th has a 'roughness' that occurs with various frequency/peak combinations. A suspected voice coil misalignment which, considering how 'high tech' the construction/assemble routine I've managed, isn't a huge surprise....
The 'high tech' cure? A piece of steel wire with a piece of aquarium tubing, hooked to the basket frame, up against the cone/voice coil intersection. A forced re-alignment...
Real 'hacksaw & hammer tech'. The KISS response. Beats the F out of a rebuild....
Meanwhile....
Larger cones=deeper bass response, no surprise there.
They can play louder=bigger radiation surface, ditto.
4 instead of 2=there IS a 'sweet spot' in the center. Depending upon the 'mix', a snare drum can appear right in front of you. A vocalist next to you. A guitar is over there, but Moves. A 'sound soup' that moves around you. It'd be a hoot to set them up in a totally empty room and see what happens. Play with knocking the 'back' pair out of phase with the front pair and see what interference patterns occur....
I'm considering pairing them, base to base, with a short sleeve, a routine I discussed with Magnasanti some pages back. I suspect the 'normal' dispersion of a walsh will return, but I'm curious to hear what having the cones 'push' against each other would do. Will they interfere with each other, exhibit cancellations, damp each other? Something unforeseen?
*S* It's fun to have my new 'toys' work.
...and I've noticed that they're power hungry. Likely due to the large and relatively heavy cones, they don't 'hit their stride' until you've turned them up a bit. Which makes for a 'dance of death' with the voice coils, which I'm interested in avoiding at this point....
...but they sure start sounding nice when you do. As before with the V.1s', and I suspect with the original Walshs', 'They sound great @ 200 watts, and blow up @ 201...'.
I will play cautiously for awhile, and begin to consider what drivers would work for the eventual V.4s'. I'm open to suggestions. Something in a 6" that can handle power, ferrofluid a plus, and preferably Cheap. Doesn't have to have a 'pedigree', as it gets carved up anyway....
...but they sure start sounding nice when you do. As before with the V.1s', and I suspect with the original Walshs', 'They sound great @ 200 watts, and blow up @ 201...'.
I will play cautiously for awhile, and begin to consider what drivers would work for the eventual V.4s'. I'm open to suggestions. Something in a 6" that can handle power, ferrofluid a plus, and preferably Cheap. Doesn't have to have a 'pedigree', as it gets carved up anyway....
