Are Apogees Bass Panels Unrepairable?

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I've tried to ask questions on other threads to get help with re-tensioning the loose woofer panel in one of my Calipers, but so far all I've seen is a German how to that shreds the existing panel.

The anti-DIY attitude of the firm that refuses to send me a replacement disgusts me. Can I get a little help here? I can fix anything, I just need a little guidance. I want to retension an Apogee bass panel that is otherwise in good condition.

The silicone minor buzz fix that Graz suppresses on his website won't do it for my left panel, but it did wonders for my right panel; it's almost perfect now. Thanks to all involved!

If it's impossible to fix a loose bass panel, then I'm OK with that too. As my hero John Lennon put it, "Just give me some truth."
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Graz has made a business decision to turn his back on the DIY crowd regarding bass that I think will ultimately doom his enterprise, but that's beside the point now.

It seems you're under the impression that many handy DIY'ers have already performed (on their own) bass panel re-tensioning, foam replacement, etc, etc, and there exists a step-by-step procedure for those efforts. I don't believe that to be the case. Very few users have attempted this and most have not documented their efforts.

The bass re-tensioning procedure....primitive as it contained in the document I posted a few days back. Grab the DIY bull by the horns and give it a go yourself. And document your effort and let us know how it goes. It would be much appreciated.

Sometimes a person searches forums and Googles for help on various subjects and finds out it might be the person in the mirror that has to make the effort. That's probably the case here.


To be fair to Graz..

A) He may have elected to supply his bass panels only to approved installers in the hope that they would be installed correctly and thus avoid any hassles with unhappy clients who may deem themselves capable of doing the job (which they might be) but then go on to screw up the process and then unfairly blame the product –such complaints would not be good for his business…

B) By selling direct to DIY installers , he may well sell more panels , the first to be screwed up and the next to get it installed correctly….

It’s his call…
just because I may produce the world’s most efficient wart remover , and make it available only to medical professionals , doesn’t mean I have to sell it to the DIY wart removalists….

I have no affiliation with Graz – nor do I own any of Apogee’s or Graz’s products.

I hope you get your Apogee’s running again- and as has been pointed out - you might have to be the trail blazer...I wish you luck - this sounds an interesting experience- part of the reason many join this forum- not just the destination but also the of luck

Regards to all
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just because I may produce the world’s most efficient wart remover , and make it available only to medical professionals , doesn’t mean I have to sell it to the DIY wart removalists….

A good wart remover businessman would probably disagree... ;)

I agree to a point...its his product to sell, but, if he were to offer a "No refund, no whining" sale of some bass panels, I, and a few others here, would surely jump on the opportunity to try.
The top rails are the problem, once removed it's just a matter of cutting the silicone from the lower rail and rolling up the ribbon as you go, removing the top rails require's a lot of patience and time as you cannot really see what you are doing and must go by feel, the other option for removing the top rail is, make a new set of top rails with all the holes in them, set up a support for a router and slowly router off the upper rails, last 1/16th of an inch soak and remove debruis, solvent will help with the removal of silicone. I have done this, it's risky but can save the 600 bucks for the ribbon. Put alot of thought into this before preceding, the risk is your's.
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The top and bottom wooden clamp rails are just screwed in and come off easily on my DS. The top / bottom wooden clamps have no silicone, and are not connected to the diaphragm at all. The side rail wooden clamps are what hold the main side to side tension, and hold up the ribbon diaphragm in place. The top/bottom wooden clamps really do nothing
DeltaStar......Thanks for all the thought You put into this ...Geat info on the Savings!
Most well not try this but it can work...
One place with the Apogees Stages An the Duetta Sg... I am geting inprovement on is working on the Big movement in the Mid-tweeter ribbons....
If the stock crossover are being used as most are an i for one say there hard to beat sound wize....Most of the Caps are out of Spek....there +-10% anyway .....i find if you just cut off one of the 10mf caps in the string that make up the 70mf in the setup that leves 60mf...I know this MAY? rases the crossover if you feel you have lost ...then you can add a 2-5mf back.....
An pull all coils lose for the there(Not glued)to the back board....

The Mid-tweeter ribbon well stop moving!
An the sound is much sweeter.. An much more real sounding....
An its much ezer to see what Jason Bloom and Leo Spiegel were go for an hearing in the great ribbons that all who hear lov.....

Thanks for any an all info on ribbons.... Apogee an other.
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When you take out the 10uf, you are raising the HP filter to a higher frequency. The reason its moving is it may be too low of a frequency in the first place, or just loose.

I checked my foam pad where the ribbon bends back (about a 9 inched below upper ribbon anchor point on my DS) and it was completely gone. I put in a new peice of foam and it tensioned (took up slack) the ribbon just enough that it now does not move as much...
All good points....
But its the caps an coils...Look the Caps are +- 10% hell thay could be at 20years of hard driving diff amps.. 100-120mf now.....An Any coils make movment when there gluded down... EZE to see this... an the should be nothing in the middel of the coils ...there best sound is when there just freeair!
Too low crossover point.. is what i am saying....there should be NO movement for the Best sound....with any tweeter... even if it just hanging... the Stage has nothing No foam... it just hangs...
For years this has been the BIg downd sides For me ...With Magnepans..
There so called True Ribbons Move all over the place....
An i have even seen some say this was good for the brain dose not work that way....i dont read moveing the book..
So any movement is out for the best sound....FOR ME!
But like i said.... Most well not do the work!

One more way to get better sound with Apogees it too just let the covers hang...puting in the bottem swes in can unaline the Drivers.....
this give better bass an highs...better sound all around that all i wont!
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An Yes when your driveing hard with a good Amp.... The Apogee or any other Ribbon Mid-tweeter....An it get so Hot you can just tuch it or hot at all....
The crossover point is to low...Or you got a Amp that can keep up!
An Guess what the Apogees are all over 20years old if thay still work now an you fix this...get a nother 20years an Better sound...not bad for just pulling a cap an moveing some coils around!......Have fun live long have good sound
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