[gregcss]

Can ribbon tweeter materials, particularly from RAAL, last forever or do they eventually break down?  I'm not talking about defective tweeters, but rather the materials deteriorating as they age. I posted this here because I am thinking about upgrading from standard STs to SCSTs.

[Phil A]

Assuming they are not abused or subject to conditions like high humidity, they should last a very long time - see this - http://www.madisound.com/manufacturers/raal/index.php

[gregcss]

Thanks. The last few sentences answers my question.

[fsimms]

Here is a video showing how to replace a RAAL ribbon.  I guess we will never have to do it though.

Ribbon Installation

Bob

[PETE6737]

On the topic of the RAAL tweeter, has anyone seen their ribbon move?  I ask this because I was listening to some music at a loud volume and for the first time I noticed the ribbon moving. I'm just wondering if it's normal.  Thanks Pete

[jules]

At a guess, what you're seeing could be feedback from your room, or other drivers, rather than movement from a frequency generated by the ribbon, which should really be far too fast to see. Neigbours allowing, you could try pointing one out a window at high volume to see if its still moves.

Jules

[PDR]

I had a pair of Carver Amazings that were built in 1987.
Gave them to a friend, those ribbons are still going strong, almost 30 years later.

[NIGHTFALL1970]

I had Apogee Acoustics Centaurs for 23 years.  One ribbon finally deteriorated.  I threw them away as cost of replacement was the same as the speakers were new ($1800.00 in 1990).

[srb]

The corrugated folded ribbon elements used in Aurum Cantus tweeters are susceptible to stretching from stiff breezes (or accidental vacuuming!).  They are inexpensive, $5 to $15, but are a bit tricky to replace.  I would assume the similarly constructed Fountek and LCY ribbons would also be similar in cost and replacement procedure.

The RAAL Flatfoil elements are not as delicate, and if replacement is needed, the part has the ribbon already suspended in a frame so replacement is a lot easier.  Madisound sells the non-OEM 70-10D replacement ribbon for $44, which is close in size to the OEM Salk RAAL (as a cost comparison only).

However, RAAL has this to say about replacement ribbons:

RIBBON REPLACEMENT KIT: ribbon replacement is made easy by our ribbon replacement kit, which is easily replaced by the user. This “kit” is in fact our SYMMLEAD® signal leading frame, holding the stretched ribbon, allowing it to snap into perfect position between the magnets.

This feature might be an obsolete one, because RAAL ribbons are destructible only by really extreme abuse or curiosity. In two years, we sent away only 3 replacement kits to customers who destroyed the ribbons by opening the drivers out of curiosity. Aside from that, our reliability record is 0% failure rate.

Steve

[ckunstadt]

I don't know how it happened, but I believe that during a move across town, one of my RAAL ribbons has sagged. I have noticed an occasional clatter that does not sound right from that speaker.  They were all boxed up for the move.  weird.  At least I have an option to replace it without sending the whole dang speaker in.

thanks for this thread.

[fsimms]

If you look at the link I posted earlier in the thread, it shows how to tighten the ribbon.  Make sure you check the screws on the faceplate to insure that they are snug before you do it though.  Also, make sure you don’t over tighten the screws.  It doesn’t even require dis-assembly of the tweeter to tighten the ribbon.   I would recommend removing the tweeter from the cabinet though as using a heat gun on the finish is probably not recommended.  I did find one screw loose on one of my tweeters but the other screw on that side was keeping the tension on the ribbon.  Please check with Jim before you do anything like what I am suggesting.

Bob

[ckunstadt]

If you look at the link I posted earlier in the thread, it shows how to tighten the ribbon.  Make sure you check the screws on the faceplate to insure that they are snug before you do it though.  Also, make sure you don’t over tighten the screws.  It doesn’t even require dis-assembly of the tweeter to tighten the ribbon.   I would recommend removing the tweeter from the cabinet though as using a heat gun on the finish is probably not recommended.  I did find one screw loose on one of my tweeters but the other screw on that side was keeping the tension on the ribbon.  Please check with Jim before you do anything like what I am suggesting.

Bob

Sweet!! Thanks!