Sierra 2 Ribbon Flexing

[jpmc]

This is how soundwaves are produced -- no movement, no sound....

Thanks David. That much I knew (for that matter most of us on this board know). I think being more specific might help. I believe a while back people spoke about RAAl showing a tightening procedure on the ribbon when it is replaced. I am sure there is a threshold as to how loose (or tight) these should be.

Are there negative effects of having a ribbon looser than the recommended amount?

[davef]

Thanks David. That much I knew (for that matter most of us on this board know). I think being more specific might help. I believe a while back people spoke about RAAl showing a tightening procedure on the ribbon when it is replaced. I am sure there is a threshold as to how loose (or tight) these should be.

Are there negative effects of having a ribbon looser than the recommended amount?

The tightening procedure you mention is only for RAAL 70-20's and that is when the ribbon diaphragm is replaced as the diaphragm replacement modules are not pre-tensioned at the factory because they first need to be installed into the housing. The ribbon in your Sierra-2 is entirely different and is set by the factory (RAAL). You will destroy your tweeter if you attempt to tighten the diaphragm as is done with RAAL 70-20 diaphragm replacements.

Yes, there can be negative effects if the tension is too high -- the tension of the diaphragm needs to be loose enough to allow the diaphragm to move freely, as it is doing. However, the design of these ribbons is such that too much tension is not possible. Again, there is nothing wrong here -- the ribbons need to move and the movement correlates directly to what frequencies are being reproduced and at what volume. If you feel the ribbon is moving too much, lower the volume.

[ematthews]

The tightening procedure you mention is only for RAAL 70-20's and that is when the ribbon diaphragm is replaced as the diaphragm replacement modules are not pre-tensioned at the factory because they first need to be installed into the housing. The ribbon in your Sierra-2 is entirely different and is set by the factory (RAAL). You will destroy your tweeter if you attempt to tighten the diaphragm as is done with RAAL 70-20 diaphragm replacements.

Yes, there can be negative effects if the tension is too high -- the tension of the diaphragm needs to be loose enough to allow the diaphragm to move freely, as it is doing. However, the design of these ribbons is such that too much tension is not possible. Again, there is nothing wrong here -- the ribbons need to move and the movement correlates directly to what frequencies are being reproduced and at what volume. If you feel the ribbon is moving too much, lower the volume.

Dave. Does this apply to the Tower Ribbon as well? As a second question, do the ribbons ever need servicing? Say like ten years from now, will I need to?

[davef]

Dave. Does this apply to the Tower Ribbon as well? As a second question, do the ribbons ever need servicing? Say like ten years from now, will I need to?

This tightening procedure that was mentioned here is for ONLY when a person replaces the ribbon diaphragm module on the 70-20xr, which is what we use in our ribbon towers. All ribbon tweeters we ship are pre-tightened by RAAL and attempting this procedure on a ribbon tweeter received from us will destroy the ribbon and, obviously, this would not be covered under any form of warranty.

To this date, in the many thousands of 70-20xr ribbons we have shipped in our towers, we have only had 2 that required servicing. One was due to being completely destroyed because the tower fell over and basically smashed the tweeter into 5 pieces and the other was due to an amplifier failure, which also took out every other component in the tower as well.

In the extremely rare occasion that a 70-20 ribbon fails, we would do the servicing here as replacing the diaphragm module is not a simple task and requires soldering skills, the correct tools and the ability to properly test the tweeter after the procedure is completed.

These ribbons do not require any type of servicing or maintenance whatsoever, regardless of their age...