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jpmc
06-13-2018, 08:00 AM
Hey all! hope all is well.

Out of curiosity, has anyone ever noticed the ribbon on the RAAl tweeter move? On one of mine I can see it flexing and moving when being used.

Appreciate any feedback!

Thanks!

Mag_Neato
06-13-2018, 09:53 AM
I have noticed that as well, pretty wild to watch the foil ripple and twist!

davef
06-13-2018, 03:22 PM
Hey all! hope all is well.

Out of curiosity, has anyone ever noticed the ribbon on the RAAl tweeter move? On one of mine I can see it flexing and moving when being used.

Appreciate any feedback!

Thanks!

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

jpmc
06-14-2018, 06:13 AM
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
06-14-2018, 05:15 PM
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
06-18-2018, 04:57 AM
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
06-18-2018, 04:08 PM
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...

Phastm3
06-28-2018, 01:40 PM
Hey all! hope all is well.

Out of curiosity, has anyone ever noticed the ribbon on the RAAl tweeter move? On one of mine I can see it flexing and moving when being used.

Appreciate any feedback!

Thanks!

I had a set of Sierra 2's a few years ago and the tweeters ripped in half...happened to 4 tweeters. I know of another sierra2 owner who had the same issue. If they are moving be ready for them to rip unless you start listening at lower volumes. I hear that the towers don't have the same issue as the sierra 2's.

jpmc
06-28-2018, 05:01 PM
I had a set of Sierra 2's a few years ago and the tweeters ripped in half...happened to 4 tweeters. I know of another sierra2 owner who had the same issue. If they are moving be ready for them to rip unless you start listening at lower volumes. I hear that the towers don't have the same issue as the sierra 2's.

This is concerning to read. I just had a ribbon tweeter replaced by Dave.

I can't really say I crank the speakers way to high. I can also tell when a speaker is being pushed to strong.

I sent in my tweeter to get replaced because a tear had formed, Dave told me it was not covered under warranty. Dave sent me pictures where he concludes that some type of debris had flown by the ribbon and torn the ribbon. I will admit it was a bit disheartened to hear this and not take a different approach.

I could've argued that there was a possibility this was during assembly or manufacturing of the tweeter itself, but I did not want to start this. I simply agreed to replaced the tweeter and cabinet (since I scratched the cabinet as I attempted to replace the tweeter by a screw that slipped).

I have always loved the way these speakers sound, for that I am a fan of. I can say that this previous experience has left a bitter sweet taste. For one I think as a customer I should've had the benefit of the doubt.

Dave did an outstanding job at replacing the cabinet.

I know that Dave seems like a pretty cool guy, but I have lost a bit of pride in saying I own these speakers after this previous tweeter replacement.

This is also the second instance I hear of a scenario like yours this past week.

davef
06-28-2018, 06:06 PM
I had a set of Sierra 2's a few years ago and the tweeters ripped in half...happened to 4 tweeters. I know of another sierra2 owner who had the same issue. If they are moving be ready for them to rip unless you start listening at lower volumes. I hear that the towers don't have the same issue as the sierra 2's.

As I have stated many times, ribbon tweeters can be sensitive to amplifier clipping, the distortion of which causes transverse waves that will cause the diaphragm to vibrate in a direction against the proper movement of the ribbon. when this happens, the ribbon actually fights against itself. This is equally damaging to dome tweeters as well (really any tweeter) - -the difference is that in a dome, the transverse waves cause excessive heat in the voice coil which eventually leads to the voice coil becoming burned. The difference is that one will "see" this damage to a ribbon tweeter and generally assume something isn't right with the ribbon, while with other tweeters, the damage is internal and can't be seen - it just eventually stops and the average consumer does not know what happened.

I remember your tweeters, this was 4 1/2 years ago and the diaphragms were basically disintegrated.
This occurred because you were listening at 100dB+ at approx. 9 feet distance from a Yamaha receiver rated at 100 watts into 2-channels. You were running all 5 channels at the same time which dramatically reduces that output power capability of the receiver (likely down to about a max of 60-70 watts all channels driven) Simple math tells us that with speakers rated at 86dB sensitivity, to reach 100dB (extremely loud), at your listening distance required more power than you receiver was capable of, thus you were clipping your receiver.

We replaced the tweeters for you and then you upgraded to a 300watt per channel amplifier. You melted these tweeters only a week later... I explained to you that at the listening distance and volume levels you were trying to achieve, these were absolutely NOT the right speakers for you, we took the speakers back from you after the return period had expired.



This is concerning to read. I just had a ribbon tweeter replaced by Dave.

I can't really say I crank the speakers way to high. I can also tell when a speaker is being pushed to strong.

I sent in my tweeter to get replaced because a tear had formed, Dave told me it was not covered under warranty. Dave sent me pictures where he concludes that some type of debris had flown by the ribbon and torn the ribbon. I will admit it was a bit disheartened to hear this and not take a different approach.

I could've argued that there was a possibility this was during assembly or manufacturing of the tweeter itself, but I did not want to start this. I simply agreed to replaced the tweeter and cabinet (since I scratched the cabinet as I attempted to replace the tweeter by a screw that slipped).

I have always loved the way these speakers sound, for that I am a fan of. I can say that this previous experience has left a bitter sweet taste. For one I don't think as a customer I should've had the benefit of the doubt.

Dave did an outstanding job at replacing the cabinet.

I know that Dave seems like a pretty cool guy, but I have lost a bit of pride in saying I own these speakers after this previous tweeter replacement.

This is also the second instance I hear of a scenario like yours this past week.

Your situation was entirely different and not related to the above. Your tweeter had a small hole in it, a puncture, and I sent you pics of precisely what caused the damage, we found debris inside the tweeter. You have been running your pair of sierra-2 without issue for 2 years now (other than (2) damaged cabinets you requested that we replace for you due to damage)

We have been there for you every step of the way, and will continue to do so.

jpmc
06-30-2018, 03:57 PM
As I have stated many times, ribbon tweeters can be sensitive to amplifier clipping, the distortion of which causes transverse waves that will cause the diaphragm to vibrate in a direction against the proper movement of the ribbon. when this happens, the ribbon actually fights against itself. This is equally damaging to dome tweeters as well (really any tweeter) - -the difference is that in a dome, the transverse waves cause excessive heat in the voice coil which eventually leads to the voice coil becoming burned. The difference is that one will "see" this damage to a ribbon tweeter and generally assume something isn't right with the ribbon, while with other tweeters, the damage is internal and can't be seen - it just eventually stops and the average consumer does not know what happened.

I remember your tweeters, this was 4 1/2 years ago and the diaphragms were basically disintegrated.
This occurred because you were listening at 100dB+ at approx. 9 feet distance from a Yamaha receiver rated at 100 watts into 2-channels. You were running all 5 channels at the same time which dramatically reduces that output power capability of the receiver (likely down to about a max of 60-70 watts all channels driven) Simple math tells us that with speakers rated at 86dB sensitivity, to reach 100dB (extremely loud), at your listening distance required more power than you receiver was capable of, thus you were clipping your receiver.

We replaced the tweeters for you and then you upgraded to a 300watt per channel amplifier. You melted these tweeters only a week later... I explained to you that at the listening distance and volume levels you were trying to achieve, these were absolutely NOT the right speakers for you, we took the speakers back from you after the return period had expired.




Your situation was entirely different and not related to the above. Your tweeter had a small hole in it, a puncture, and I sent you pics of precisely what caused the damage, we found debris inside the tweeter. You have been running your pair of sierra-2 without issue for 2 years now (other than (2) damaged cabinets you requested that we replace for you due to damage)

We have been there for you every step of the way, and will continue to do so.

I can't really say much about the previous poster and his issues, I can only comment on my experience.

Dave, I never compared his situation with mine. I understand they were different situations. I simply shared my experience with my tweeter.

It does concern me that the old ribbon (speaker that has the original ribbon) moves much more than the new one. Is it that there is a break in period for the new one since it's new and tight? I don't know. Will it eventually loosen as much as the old one? Who knows... Does this have an impact on one tweeter producing frequencies differently than the old one. Maybe.

I often tend to stay behind and not comment immediately because I like to truly analyze situations and responses. I am a mechanical engineer. I make flight critical parts for big oem aerospace companies everyone here has heard of (including defense). To receive a description like "This is how soundwaves are produced -- no movement, no sound.... " and "If you feel the ribbon is moving too much, lower the volume." are unnecessary and can come as an insult to ones intelligence. It's not an issue to me but it might be to some on here that are also looking for objective answers.

I will say it again. I love these speakers, I truly believe these will eventually hold to be a classic wanted set years from now.


Full disclaimer: Dave has repaired one cabinet when my speakers were new because I used sorbothane on the bottom of the speaker and damaged the Bamboo.

This second repair was due to the tweeter tearing on an edge and with time the tear extended. As I attempted to replace the tweeter I scratched the cabinet with a screw that slipped.

His workmanship, and his attention to detail to match my older cabinet was second to none. I do not disregard your efforts.

Thank you for supporting me with your products. I appreciate everything you and Dina do to stand behind them.

I guess this is why I am a bit confused with feedback on this thread since I would never expect this.

Have a wonderful day everyone.

davef
06-30-2018, 05:30 PM
I can't really say much about the previous poster and his issues, I can only comment on my experience.

Dave, I never compared his situation with mine. I understand they were different situations. I simply shared my experience with my tweeter.

It does concern me that the old ribbon (speaker that has the original ribbon) moves much more than the new one. Is it that there is a break in period for the new one since it's new and tight? I don't know. Will it eventually loosen as much as the old one? Who knows... Does this have an impact on one tweeter producing frequencies differently than the old one. Maybe.

I often tend to stay behind and not comment immediately because I like to truly analyze situations and responses. I am a mechanical engineer. I make flight critical parts for big oem aerospace companies everyone here has heard of (including defense). To receive a description like "This is how soundwaves are produced -- no movement, no sound.... " and "If you feel the ribbon is moving too much, lower the volume." are unnecessary and can come as an insult to ones intelligence. It's not an issue to me but it might be to some on here that are also looking for objective answers.

I will say it again. I love these speakers, I truly believe these will eventually hold to be a classic wanted set years from now.


Full disclaimer: Dave has repaired one cabinet when my speakers were new because I used sorbothane on the bottom of the speaker and damaged the Bamboo.

This second repair was due to the tweeter tearing on an edge and with time the tear extended. As I attempted to replace the tweeter I scratched the cabinet with a screw that slipped.

His workmanship, and his attention to detail to match my older cabinet was second to none. I do not disregard your efforts.

Thank you for supporting me with your products. I appreciate everything you and Dina do to stand behind them.

I guess this is why I am a bit confused with feedback on this thread since I would never expect this.

Have a wonderful day everyone.

Hi JPMC,

My sincerest apologies, my post about the ribbon needing to move was really just a friendly tease to you on a personal level well knowing how meticulous you are. Sometimes a person can be overly meticulous about things. You even admitted this to me when I suggested saving the $$$ and keeping the original cabinet with the damaged finish on the bottom which was due to that oily residue produced from the sorbothane that actually ate into the polyester resin clear coat. I didn't mean to offend so I do apologize...

That said, as meticulous as you are, I am even more so and I inspect and test every single speaker we ship - even with service items sent in, even if we don't end up servicing it. However, my memory is not as good as it once was and I am not sure if you sent both speakers back to us so we can match the cabinet or only one speaker?

However, I do recall telling Joe and Dina how meticulous you are so that when they matched the cabinet for you, I eventually found out they had to examine about a dozen different cabinets to get it exactly right. They weren't happy about this as it took a few hours, but I am the boss (well, sometimes at least :o )...

The compliance on the ribbons will slightly loosen over time, I wouldn't really call it breaking in though. When we first started working with RAAL, they actually sent their chief technician over to visit us and we spent a full day going over ribbon tension. He proved to me that (and I backed this up by my own measurements) that the tension doesn't affect sound quality, provided that it isn't overly loose or overly tight. The design is such that the tension is controlled by a material that is adhered to the foil and then adhered to the housing, it is similar to heat shrink.

Thinking back, we have had your speakers in the shop on 2 (3?) separate occasions now and this last time, I do not recall if you sent just the damaged cabinet back or both? Because if both, they would not have been shipped to you without me fully testing both of them, of which I am confident they are perfectly matched performance-wise...

If you sent only the one cabinet back, send me an email and let me know. I will make shipping arrangements to get them both back so we can test both of them together. I do recall that you originally installed the replacement tweeter into the cabinet itself or am I wrong about this.

Also, when we replaced the first cabinet for you (the first time), did you send back both cabinets or just the single cabinet? Is this the same cabinet with the ribbon that seems to be looser or the cabinet with the ribbon that seems to be tighter? Did you swap the left/right speakers to 100% confirm that one tweeter isn't moving more than the other due to receiving a different signal? Remember, with stereo - the left and right source material will be different. Also, do not test by sending sine wave signals (even swept sine waves) to the ribbons -- this can be damaging and can actually cause the ribbon to tear or stretch.

Sorry for all the questions, it is hard to remember the exact circumstances at this point...

jpmc
06-30-2018, 06:15 PM
Hi JPMC,

My sincerest apologies, my post about the ribbon needing to move was really just a friendly tease to you on a personal level well knowing how meticulous you are. Sometimes a person can be overly meticulous about things. You even admitted this to me when I suggested saving the $$$ and keeping the original cabinet with the damaged finish on the bottom which was due to that oily residue produced from the sorbothane that actually ate into the polyester resin clear coat. I didn't mean to offend so I do apologize...

That said, as meticulous as you are, I am even more so and I inspect and test every single speaker we ship - even with service items sent in, even if we don't end up servicing it. However, my memory is not as good as it once was and I am not sure if you sent both speakers back to us so we can match the cabinet or only one speaker?

However, I do recall telling Joe and Dina how meticulous you are so that when they matched the cabinet for you, I eventually found out they had to examine about a dozen different cabinets to get it exactly right. They weren't happy about this as it took a few hours, but I am the boss (well, sometimes at least :o )...

The compliance on the ribbons will slightly loosen over time, I wouldn't really call it breaking in though. When we first started working with RAAL, they actually sent their chief technician over to visit us and we spent a full day going over ribbon tension. He proved to me that (and I backed this up by my own measurements) that the tension doesn't affect sound quality, provided that it isn't overly loose or overly tight. The design is such that the tension is controlled by a material that is adhered to the foil and then adhered to the housing, it is similar to heat shrink.

Thinking back, we have had your speakers in the shop on 2 (3?) separate occasions now and this last time, I do not recall if you sent just the damaged cabinet back or both? Because if both, they would not have been shipped to you without me fully testing both of them, of which I am confident they are perfectly matched performance-wise...

If you sent only the one cabinet back, send me an email and let me know. I will make shipping arrangements to get them both back so we can test both of them together. I do recall that you originally installed the replacement tweeter into the cabinet itself or am I wrong about this.

Also, when we replaced the first cabinet for you (the first time), did you send back both cabinets or just the single cabinet? Is this the same cabinet with the ribbon that seems to be looser or the cabinet with the ribbon that seems to be tighter? Did you swap the left/right speakers to 100% confirm that one tweeter isn't moving more than the other due to receiving a different signal? Remember, with stereo - the left and right source material will be different. Also, do not test by sending sine wave signals (even swept sine waves) to the ribbons -- this can be damaging and can actually cause the ribbon to tear or stretch.

Sorry for all the questions, it is hard to remember the exact circumstances at this point...

No worries Dave, I am not offended. Thank you for clearing all of these details up. Receiving the technical aspects from your products is often a big part of what stands you apart from competitors along with making a badass product :)

My speakers have been twice at your shop. The first time I had sorbothane pads between the speaker and the stands. I sadly learned that the moisture in these pads ruins the finish on the bamboo. I sent you both cabinets and you extended a discounted price because the speakers were so new (Also you felt sorry for me lol)

That time both speakers were tested and you provided me results with the return.

This recent incident we arranged for a tweeter replacement. When I tried to remove the old one I ended up scratching the cabinet for which I sent only the damaged one to you where you replaced the cabinet and installed the replacement tweeter (I had heard from Dina that a day was spent sorting me a matching cabinet). The speakers could not be tested because I only sent one :(

The cabinet that has the ribbon that seems to be looser is the original cabinet that I sent when I damaged the cabinet by using sorbothane. The ribbon that seems tighter (barely moves) is the ribbon that was replaced a couple of weeks ago.

I switched the speaker with the looser ribbon to the other channel (where the tighter ribbon is being fed off of) and the same behavior, so it's not a behavior or a function of the channel from my understanding.

From a performance perspective, I can't hear anything negative, they sound great!

I am very appreciative of the all of the efforts from you and Dina.

Thanks for responding!

Thanks for replying back Dave.

davef
07-03-2018, 01:49 AM
No worries Dave, I am not offended. Thank you for clearing all of these details up. Receiving the technical aspects from your products is often a big part of what stands you apart from competitors along with making a badass product :)

My speakers have been twice at your shop. The first time I had sorbothane pads between the speaker and the stands. I sadly learned that the moisture in these pads ruins the finish on the bamboo. I sent you both cabinets and you extended a discounted price because the speakers were so new (Also you felt sorry for me lol)

That time both speakers were tested and you provided me results with the return.

This recent incident we arranged for a tweeter replacement. When I tried to remove the old one I ended up scratching the cabinet for which I sent only the damaged one to you where you replaced the cabinet and installed the replacement tweeter (I had heard from Dina that a day was spent sorting me a matching cabinet). The speakers could not be tested because I only sent one :(

The cabinet that has the ribbon that seems to be looser is the original cabinet that I sent when I damaged the cabinet by using sorbothane. The ribbon that seems tighter (barely moves) is the ribbon that was replaced a couple of weeks ago.

I switched the speaker with the looser ribbon to the other channel (where the tighter ribbon is being fed off of) and the same behavior, so it's not a behavior or a function of the channel from my understanding.

From a performance perspective, I can't hear anything negative, they sound great!

I am very appreciative of the all of the efforts from you and Dina.

Thanks for responding!

Thanks for replying back Dave.

Thank you for clarifying this for me.

OK -- based on your post in the other thread regarding hitting the peak output indicator on the ATI 1802 while only sitting 4.5 feet away, we need to take another approach to this as something isn't right. I have personally measured this amp producing a clean 200 watts into a static 8 ohm load, it is a beast of an amplifier. You will do serious damage to your hearing pumping this much power into the Sierra-2 at your listening distance, and damage the speakers as well...

Next step - you need a calibrated SPL meter to measure the peaks you are hitting at your listening distance... It is possible there is something wrong with this amp, or like you mentioned in the other thread, you might be going deaf ;)

Once we figure out what is actually going on here, I might want both of your speakers back here for complete evaluation...

I will respond more in the other thread

Mag_Neato
07-03-2018, 06:54 AM
Interesting.

I run an ADCOM GFA-5500 200 watt@8ohms amp (350watts@4ohms). It has clipping LEDS for each channel. I have witnessed the ribbons moving as well, have played at VERY loud SPL(mid 90's), and have never seen so much as a flicker from the LEDS. Distance was around 8-9ft.