I see the 4 mounting clamps/blocks for the panel. The top and bottom clamps appear to have some clearance and free play. I can see a thin strip of foam underneath which I guess is the same thickness as the foam on the grille side of the clamps.

The clamp nearest the mid/tweeter ribbon has some extra screws and appears to have some sort of adjustability.

I guess if the foam is replaced the panel will need to be tensioned again.

It would appear there maybe a better option instead of foam. I was thinking urethane o-ring and routing a groove in the clamping blocks.

Foam replacement is possible ONLY for the upper horizontal clamps in any planar Apogee. When new there is damping foam above and below the bass ribbon on all sides so replacing the foam on the only accessible clamps is usually a futile move. In the Stage this problem is compounded as there is no lower clamp system, the foam just being the thinnest available, and laid on the surface of the backboard that forms the "underclamp". As time goes by this foam turns to dust under the constant pressure, and the dust presses into the adhesive that the foam is backed with. The ribbon bonds to the adhesive and in the case of the tuning side the ribbon ceases to have correct tension, and the buzz starts.

My unpopular opinion is the Stages were designed with serious cost cutting ideas, not as a long-lived little brother, but as a shorter-lived intro to planar Apogees, a commercial stepping stone to larger Apogees. Many Stages are over 15 years old, and have given longer service than originally designed for. Panel replacement is a problem, as developing a panel replacement for these is a time consuming and costly exercise, that has always had two reasons against me investing this time and energy. Those things are the HUGELY variable quality of Stages. Magnet array tolerances being a real problem, an accurate ribbon over an inaccurate magnet array is something that won't last or play purely. Add to that the fact that any real Stage refurbishment involves some woodwork that should have been incorporated into the original design and the whole bass restoration project is costly, many not considering it commercially viable. The second reality is that there is a source of Stage panels out there, the original Apogee panels from a/d/s that have been sold regularly at less than 50% manufacturing costs by Bob Dragunas. Important - I don't blame Bob for this at all - he was given a pile of panels by a/d/s and did what anybody would do, priced them to sell. Perhaps there are some left, perhaps they are sold - I don't know. I always said that panel stock would eventually dry up and when they did that would be that, and that's how it panned out I guess.

People have looked to me for a replacement and in the past I really considered it knowing the problems but every dead Stage pair that popped up and was offered for research never actually made it here, and every enquiry I had was given the option to contact Bob disappeared in one way or another.

Who knows - one day a dead pair might make it here without time constraint or commitment (there are some Stages down here), and if/when they do I may be able to work out a method of repair with the installers that would be useful for all.

And that is because it is glued to something?

And that glue can't be removed without destroying the panel?

So a new panel won't be destroyed by gluing it to the blocks?

I would be interested in participating.

I may also be able to get to the bottom of the bass panel intricacies and where I am at - on this discussion topic.

You are correct, the bass ribbon is sandwiched between two blocks of wood (clamps) via glue. Once this is disassembled, the ribbon is demolished.

It's unfortunate because if it were designed differently, we could probably somehow save the ribbon while re-foaming, or better yet install them ourselves.

So is there damping foam on the vertical clamps?

Is there foam on all four edges of the ribbon on the front side or opposing sides of the clamps?

Is the bass driver only glued to the vertical clamps and not the speaker frame? If it is only glued to the clamps then removal and replacement may be possible and practical.

Maybe it is a question that only the installers would know. I did a lot of searching on this forum and it was difficult to find a definitive answer.

I did read about re-tensioning/tuning the panels but as I say, not clear. Well if no one can tell me here I will keep searching.

If anyone knows for sure if there is glue on the frame side of the driver it would be good to know. Because removal and refitting could be done with a jig. But the clamp side may be a different story.

Isn't there a video somewhere on how to do the driver replacements.

Thanks for all of your replies.

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So that would mean that tuning the Stage bass panels is impossible without destroying them unless it is being done during installation of a new panel.

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Exactly. If you want to re-tension or "tune" a bass panel, you must do that as you are installing a brand new pair of bass panels. That is, if you could FIND a new pair of bass panels somewhere ...

Graz does not make bass panels for Stages because there seems to be too much physical variance between existing Stage speakers to make it practical for him to do so.

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Originally posted by geddie:
Exactly. If you want to re-tension or "tune" a bass panel, you must do that as you are installing a brand new pair of bass panels. That is, if you could FIND a new pair of bass panels somewhere ...

Graz does not make bass panels for Stages because there seems to be too much physical variance between existing Stage speakers to make it practical for him to do so.

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However, I know that it is only a matter of time before the Stages get the dreaded buzz.

Graz, I have a question for you.

Since repairing the bass panels isn't practical, either in an engineering or economic sense, could you simply design and create a new replacement Stage? I mean a complete speaker, with new bass and MRTW ribbons, and a redesigned crossover.

I would expect the result to be a big upgrade over the stock Stages in my Mini-Grands.

Steven

Im trying to see this Appogee design in my head based on comments in this forum and pics.
I see clamps at ribbon edges. The ribbon is between the clamps. There is glue between the ribbon and the clamps. Both clamps have glue. Where the ribbon comes out of the clamps, right at the edge of the clamps, is the foam. Foam on both sides of the ribbon. Foam degrades, ribbon slaps against edges of clamps or somthing that the foam used to damp.

Ok if this is even remotly correct then it seems to me there may be a crude way to deal with this (without diaphram replacment) that just might give at least 90% ( maybe more) of perf of replaced foam.

Heres what I see in my head. Take the front cover off and look at where the foam is around the diaphram. If the foam was completly rotted away then there would look like a gap between the clamp and the diaphram. Or maybe the foam is still there and just partialy rotted away. Eather way, why couldnt this space where the foam is/ should be, be filled with silicone calk. Very carfully of course so as not to put any dents in ribbon with your finger or calk gun. Maybe cut out a crude calk spreding knife from thick craft paper or plastic,that fits over the edge of the clamp and comes about 2 or 3 mm away from ribbon. Use the ribbon Clamp structure to hold the "knife" away from ribbon, and just spread the silicone bead along the edge where the foam would be.I supose you would want to practice on somthing simulating the speaker untill you have a methode that works.
The idea is to "glue" the ribbon edge to the clamp in the space that used to be occupied by the foam using a soft compliant adhesive.100% pure silicone calk seems best to me. I have used this on many ribbon designs.If there is a lot of foam still there then the silicone would be kindof a "skin" over the foam from ribbon surface to clamp.

I understand only one side(front) can get this treatment but that may be just fine. The ribbon would be held in position by the glue even if only one side is done. May have to experament with the thickness of calk untill enough to "damp" the buzz out.My guess is you will need at least 2-3 mm thick "skin".

One other idea. This would be where there is no foam left. Completly rotted out. There is a vynl based foam weatherstriping in an arosole can available at hardwear stores. Its like the expanding urathane foam used for insulating around windows and such in houses but it doesnt get hard like that expanding foam. This stuff is vynl based foam that cures soft and has a very very good damping quality. May even exceed the stock foam!However it is rather fragile. Im not sure if it would hold up to forces. Also it will rot from sunlight over time. Silicone will be here long after U a I . It squerts out of a straw from a can. Again you would need to experament on somthing other than speaker till your good at it.

Now I know this all sounds crazy and someone who has seen the insides of these speakers may have much to say about the above ideas , However I have done a ton of work like this.

Think about this carfully. If you have a pair of Stages that you cant listen to because of the buzz but were working fine up till that point ,then you may be doing everyone a service by trying this. Eather the silicone or the foam can be removed latter if new diaphrams become available.

The repair requires;-

1) A new double sided ribbon
2) The speakers' back board be routed to rebate the foam, to ensure a long life
3) The ribbon be installed and tensioned by a person who knows how (installer)
4) Properly aligned magnets

CAN THE RIBBON PARTS BE MADE BY ME? YES.

For an effective perfect repair the magnets should be in perfect order and alignment, unfortunately this was not the case for many Stages. Many had/have their own distortion signatures because of this. This is a worry - as a newly restored speaker is possibly coming under the most serious scrutiny it ever has, and it's "signature distortion" may be heard for the first time by it's third owner that probably never heard it working. Who would get the blame?

Economics - who would be willing to pay for such work and seriously engineered parts, made in 2008 with small production? And who would compare the costs unfavorably to previously supplied bass parts only from a source that obtained a bulk supply for zero costs? Would Bob come back to ditch his last Stage bass parts (if he has any left) in an untimely way to kill off a lasting solution?

Prototyping. I completely understand the Stage problem, but making a ribbon design in kapton would require some prototype work, and that would require some Stages here, without pressure to come up with a production solution in a set time. So far - none have come up within reasonable distance (anywhere in Australia). Exterior options have all been unboxed and would have to be shipped here, import taxes and packing paid for.

And at the end of the day the END CLIENT has to be willing to pay for parts/rework/installation, and there would have to be quite a few that would want to do this - so far I could easily count those serious on one hand! I have been contacted by over 100 people curious about the parts, but all have either managed to contact Bob Dragunas and got some old ribbons, or have decided the task isn't worth the effort or expense. No exceptions. I have tried calling Bob to ask how many panels he has left for months on his home number that he used to answer at all times, and just like all the other numbers!

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So that's the position. If anybody hears of dead Stages that I can ever get here, please email me...Graz[/B]

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Does anyone else want to contribute money to buy and ship these (or other) speakers below to Graz? (I'll send $100 of my own provided someone else that you all trust receive and group the funds - for purchase of these or other speakers).

These stages are probably not the best choice. As they have been exposed to smoke in a house fire and in an unrelated incident the right Stage was fed excessive current from a heavily clipping amplifier damaging its MRTR and likely more. Additionally they are located in Anchorage AK without boxes (and it did not sound like the owner would be proficient at crate building last I spoke with him). I do hope someone saves them from the landfill though.

Original CL posting below:

apogee stage speakers

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Reply to: see below
Date: 2007-12-20, 9:40AM AKST

one speaker is blown,and needs a new ribbon.Im only apealing to serious audiophiles,or techs that have resources to be able to repair them.paid 3000.00 new ten years ago. make offer. call shawn at 223-7013

Location: anchorage
it's NOT ok to contact this poster with services or other commercial interests

PostingID: 499646980

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Bronson

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Originally posted by Graz:
etc etc

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If we only had a faq we could paste this kind of info into...

And I think it is a good thing when people are interested in their speakers.