Anyone making Apogee bass panels?

The big floppy mid ribbon has charms I dont think a bunch of small planer mids and tweets can do.

Free swinging ribbons have the advantage of very very low resonant freq. This pays dividend in the lower mids that im not sure can be achieved in a small planer diaphragm.

As well the Scins have tru foil only ribbons. No backing material and adhesive.

Subjectively I feel the foil only ribbons can do micro dynamics better than the laminated versions BUT you have to tailor everything just right to avoid resonant issues.
That said the laminated versions can be perhaps subjectively "sweeter" but can sometimes sound slightly veild compared to FOs.

I cannot at all make this case through measurment and im not at all sure one is "technically " better, BUT after building and side by side compare of probably 1000 mrts of both, this is where my thoughts land.

In fact my own ribbon work has been in part to find a happy medium between the two.
 
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Yes their free hanging ribbons, doesn't matter how loud you play music, they never twitch or move, extremely stable. The Diva's are a different animal, like the duetta sigs, they twitch and bounce around when it gets loud,, replace Diva mids yearly, or sooner,,, the tweeter ribbon never give's a problem,,,been thinking about going to a foil hanging in the midrange like the scintilla, it would be 1.125 wide for the gap,,BUT would be just about a dead short.
 
Those pulsing tweeters were unique and wonder if there were frequency cancellations
since they were right in front and along the edges of the mid foil.
I never heard of anything amiss on measurements or sound quality though

This was the only model constructed this way. Probably too labor intensive And costly for continued production.


Regards
David
 
You can certainly convert the Diva to a foil only mid ribbon

BUT I caution you here, I believe the Diva crosses over from mid to tweet at around 9 khz and the Diva, laminated/ small corrugation ribbon, is well behaved enough to cross that high.
If you make a big FO for the Diva mid with corrugations you may find it difficult to get a smooth response up to 9K. There will likely be a strong wiggle and a bunch of energy storage somewhere in there. My guess, depending on size of corrugations, you will see trouble between 3 and 7 khz. Close mic waterfall plots will show it. The ear will hear it as edgy brightness. And traps dont filter the sharp peaks out all that well. Traps better suited to smooth long symmetrical rise and falls

The Sins get away with this I think because they cross over down around 3 khz and the wider mid ribbon is more directional in dispersion


BTW a word on Apogee and other similar speakers sound. Ive had Apogee along side many many protos of other similar designs on deck for months just playing with exact levels, crossover points, rakes, etc.

I can say this, this type of speaker can go from good to truly top class with very small changes in the mentioned areas. Its startling at times how convincing even crude setups can sound when everything is dialed in. My suspicion is many have not heard what these this are capable of simply because every room/setup is so different.

Ive had Diva mid tweeter copies where the vocals can be utterly convincing IF everything is right . Even 1/2 db changes in level or rake of the mids and up can bring the magic
 
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All this talk of refurbing Apogees got me re-interested in finishing my Scinnies bass panels...anyone know where I can get new Mid/Tweeter ribbons for Scinnies? Also would be interested in trying a DIY effort for an experiment...

A long while ago I made my own ribbons for an Apogee caliper tweeter - I used the thinnest kitchen aluminum foil, put it thru my crank spaghetti maker to get a nice flat 1/4" wide strip (don't laugh - it worked a treat), and then ran thru a corrugator my wife had from Michael's craft stores.

I did not have kapton backing on the three strips, but I scotch taped the three sections every foot or so down its length to keep them apart, and connected them in series, with an additional 2 ohm resistor to get 4 ohm. Then used a weight (don't remember what it was - but was from installation instructions for an actual replacement tweeter ribbon) and set the ribbon tension. It worked out well, was it as good as original? Donno, but i was impressed that basic thin kitchen foil sounded as good as it did...
 
Caplinq
Has sputtered aluminum on Kapton total thickness (25.5 um) so a little over .001”

Part # PIT1N-ALUM/500-3

So you would have to find a way to etch off your traces
Excellent material from the looks of it
Not sure if it would hold a corrugation consistently as its appears to have a spread of tolerance variations..,
Free air res. is going to go up as well

Not bad on prices - available in 3 or 33 meters /500 mm width


Regards
David
 
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Have you priced bass panels from Graz? Oh, that's right...you can't even by them.

I would think for some real Apogee hobbyist capable of rebuilding his panels this would be a steal.

This may be a stupid question but is aluminum the only metal option for this process? Why not copper?

Single-sided Pyralux(R) AC Features Excellent Dimensional Stability


The spec sheet here:

https://www.dupont.com/content/dam/...rmation/documents/PyraluxACclad_DataSheet.pdf

...has the thinnest product at 21um (AC 091200E), 9 for the copper and 12 for the film.
 
Aluminum has 61% the conductivity of copper but is 30% lighter.
If you match the electrical conductivity of both , alum. is 50% lighter

Another issue is copper corrosion overtime at these thickness levels and whether you will coat the metal which adds mass
Looks like 250’ min order and copper is more expensive too boot

So already you have a weight penalty unless you want mass and a lower FR
 
How about this:

TR-Clad™ Flexible Laminates

9 um copper on 2 um film! Even with another front film or coating it's still light. Oh, they also make it with aluminum, 4um and up.

My thought years ago was to make a panel/ribbon without corrugations but embossed with a specific semi-random pattern, to stiffen the material and control resonances. it was a specific pattern I had seen on another prototype ribbon. Something like what RAAL does. Getting a bit off topic here...
 
So here is the corrugation and its not like you can find an abundance of choice out in the market on what will work.
We do want a cheap solution to work with.
Even though it doesn’t match exactly, the actual height is in comparison is the same although it looks higher.
My cuts are bigger and that will more than likely result in less output but every frequency graph I have seen on Apogees shows huge bass gain relative to the rest of the spectrum.
The Scintilla being one of the worst at 10 to 15 db so maybe a good thing in the end.
Time will tell and a new template with thinner cuts is possible.
View attachment 794504
This is the first panel attempt I made so go easy

This i so impressive. I have worked on a corrugator for many years and I have not been successful so far. The problem I have experienced is that it misalign during the corrugation. I am now working on a new one. Could you share a picture of your corrugator? I am at the moment using uncorrugated aluminium and foil witch works, but I am wondering how a properly corrugated will sound. By the way I am using a DIY Krell KSA100 II (Jims Audio) with a little modification with 12 output transistors pr. side. Fully biased into class A and it sounds wonderful. 1000VA Toroidal trafos pr. side. This only shows the potential of this type of speaker and the ability it has to surprise you time and again.