Announcement

Collapse

INTRODUCTION - PLEASE READ FIRST TO UNDERSTAND THIS FORUM!

"This Harbeth User Group (HUG) is the Manufacturer's own managed forum dedicated to natural sound from microphone to ear, achievable by recognising and controlling the numerous confounding variables that exist along the audio chain. The Harbeth designer's objective is to make loudspeakers that contribute little of themselves to the music passing through them.

Identifying system components for their sonic neutrality should logically proceed from the interpretation and analysis of their technical, objective performance. Deviations from a flat frequency response at any point along the signal chain from microphone to ear is likely to give an audible sonic personality to the system at your ear; this includes the significant contribution of the listening room itself. To accurately reproduce the recorded sound as Harbeth speakers are designed to do, you would be best advised to select system components (sources, electronics, cables and so on) that do not color the sound before it reaches the speakers.

For example, the design of and interaction between the hifi amplifier and its speaker load can and will alter the sound balance of what you hear. This may or may not be what you wish to achieve, but any deviation from a flat response is a step away from a truly neutral system. HUG has extensively discussed amplifiers and the methods for seeking the most objectively neutral among a plethora of product choices.

HUG specialises in making complex technical matters simple to understand, getting at the repeatable facts in a post-truth environment where objectivity is increasingly ridiculed. With our heritage of natural sound and pragmatic design, HUG is not the best place to discuss non-Harbeth audio components selected, knowingly or not, to introduce a significantly personalised system sound. For that you should do your own research and above all, make the effort to visit an Authorised Dealer and listen to your music at your loudness on your loudspeakers through the various offerings there. There is really no on-line substitute for time invested in a dealer's showroom because 'tuning' your system to taste is such a highly personal matter. Our overall objective here is to empower readers to make the factually best procurement decisions in the interests of lifelike music at home.

Please consider carefully how much you should rely upon and be influenced by the subjective opinions of strangers. Their hearing acuity and taste will be different to yours, as will be their motives and budget, their listening distance, loudness and room treatment, not necessarily leading to appropriate equipment selection and listening satisfaction for you. Always keep in mind that without basic test equipment, subjective opinions will reign unchallenged. With test equipment, universal facts and truths are exposed.

If some of the science behind faithfully reproducing the sound intended by the composer, score, conductor and musicians over Harbeth speakers is your thing, this forum has been helping with that since 2006. If you just want to share your opinions and photos with others then the unrelated Harbeth Speakers Facebook page http://bit.ly/2FEgoAy may be for you. Either way, welcome to the world of Harbeth!"


Feb. 2018
See more
See less

Noises on C7ES3 Radial driver

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • Noises on C7ES3 Radial driver

    Dear Alan,

    Today I discovered noises on my right C7ES3 right speaker when playing solo piano pieces. Left speaker is fine. Noises persist on the right speaker even after I swapped the left/right speaker connections on the integrated amplifier.

    I read several posts in the Hong Kong Harbeth HiFi forum that it is probably due to over-driving the unit. Is it the case? I am getting really puzzled because I seldom play above the moderate level.

    Anyway, my C7ES3 is just over 1 year old and warranty just expires. Should I bring both speakers to the HK dealer for repair? How will the repair process be? I am concerned whether the local repair process actually matches the high building standards in the UK. Will they perform matching with the left speaker during repair? How about the records in the Harbeth log book? Will they get updated as well?

    Thanks.

    Regards,
    John Lee
    Hong Kong

  • #2
    Turn the driver around

    Hi John,

    Wishing you a healthy and happy 2009.
    Try turning the driver around, it works for me.

    Cheers..

    Comment


    • #3
      Re: Noises on C7ES3 Radial driver

      Originally posted by sunshine View Post
      Hi John,

      Wishing you a healthy and happy 2009.
      Try turning the driver around, it works for me.

      Cheers..
      Hi sunshine,

      Thanks for your reply. Could you elaborate more on the details?

      By the way, how did your driver get into the problem? Playing too loud? I am worried whether it is the problem with my amplifier (Primare I30).

      Regards,
      John

      Comment


      • #4
        Re: Noises on C7ES3 Radial driver

        Hi John,

        I do have a tendency to go loud(claimed by my family members), but i doubt it is due to loudness. I am not electronically sound, but was advised to give the driver a 180 degree turn. So far so good, do not know how loud i play, but at a volume that i enjoy most.

        If you do plan to turn the driver around, when you unscrew your driver's bolts, try to feel how tight it was tightened and when securing them, do not over tighten it.

        Comment


        • #5
          Rotate woofer through 180 degrees & distributors support

          It's impossible to say what the problem is or could be just from the description. I absolutely agree that rotating the driver through 180 degrees may help even out the drag of gravity.

          Turn off your amplifier before you attempt to remove and rotate the driver but please DO NOT UNPLUG THE WOOFER from its cables.

          One thing I should make clear is this: I may from time to time be able to comment publicly on an issue like this but as a matter of courtesy, if you have an issue that may ultimately need a physical solution you must talk with your local supplier. We here will gladly give our opinion and advice but we cannot bypass our well-established distribution chain to provide physical solutions direct from the factory to the user. We work through our distribution chain as per our ISO9001 mandate to gather useful feedback in a structured way from distributors. Our distributors and retailers have a mutual interest and motivation in having you as a 100% happy customer.
          Alan A. Shaw
          Designer, owner
          Harbeth Audio UK

          Comment


          • #6
            Re: Noises on C7ES3 Radial driver

            Originally posted by sunshine View Post
            Hi John,

            I do have a tendency to go loud(claimed by my family members), but i doubt it is due to loudness. I am not electronically sound, but was advised to give the driver a 180 degree turn. So far so good, do not know how loud i play, but at a volume that i enjoy most.

            If you do plan to turn the driver around, when you unscrew your driver's bolts, try to feel how tight it was tightened and when securing them, do not over tighten it.
            I would first try to turn the entire speaker by 180 degree. If this helps then you can turn the driver.
            Just an idea ...

            Comment


            • #7
              Re: Rotate woofer through 180 degrees & distributors support

              Originally posted by A.S. View Post
              It's impossible to say what the problem is or could be just from the description. I absolutely agree that rotating the driver through 180 degrees may help even out the drag of gravity.

              Turn off your amplifier before you attempt to remove and rotate the driver but please DO NOT UNPLUG THE WOOFER from its cables.

              One thing I should make clear is this: I may from time to time be able to comment publicly on an issue like this but as a matter of courtesy, if you have an issue that may ultimately need a physical solution you must talk with your local supplier. We here will gladly give our opinion and advice but we cannot bypass our well-established distribution chain to provide physical solutions direct from the factory to the user. We work through our distribution chain as per our ISO9001 mandate to gather useful feedback in a structured way from distributors. Our distributors and retailers have a mutual interest and motivation in having you as a 100% happy customer.
              Dear Alan,

              Thanks for your comment and information. I was (actually still am) very upset at New Year's day when I discovered the problem. Nobody would be at work then, and thus the post at this forum. I am well aware of the support procedure, but hope I can be excused, given the imaginable emotional let-down at the first day of a new year.

              I did talk to Mr. Chan (HK supplier) eventually after the holiday. He is a very nice person. For subsequent case follow up, I will follow the established procedure.

              Finally, thanks Mr. Chan, sunshine & TW for your suggestions. I will do some more tests in the coming few days. After initial testing, I think my left Radial driver is also damaged but to a lesser degree. More tests are needed to confirm.

              Regards,
              John

              Comment


              • #8
                Accidents, honesty and distributor support

                No need to apologise - I completely understand your position during a holiday break when everywhere is closed. I just wanted to make a general point that distributors like Peter Chan and his son Henry are very much on your side and want to help. What definitely adds weight to solving an issue is if the user is frank and honest; accidents do happen and, for example, youngsters do damage their parents hi-fi. We are obliged under our ISO9001 procedures to appeal for the occasional suspect parts and have them returned for video-dissection because we need to know how and why they misbehaved and whether that results from a manufacturing issue or an issue outside of our control in the users hands or even in transit.

                As a result of that analysis we can readily detect the signs of overload etc., although sometimes it must be admitted, there is just no clear explanation. It's far better for all concerned to be up front about the events leading to the problem, as this leads to a quicker, cheap solution for everyone. As I said, accidents sadly do happen.

                By the way - we have some video archives of dissections of drive units in close-up with a commentary and we'll prepare an example to be uploaded now the Flash video system is online.
                Alan A. Shaw
                Designer, owner
                Harbeth Audio UK

                Comment


                • #9
                  Re: Noises on C7ES3 Radial driver

                  Originally posted by T.W. View Post
                  I would first try to turn the entire speaker by 180 degree. If this helps then you can turn the driver.
                  Just an idea ...
                  Dear TW, sunshine,

                  Over the week I have been carrying out a number of tests and would like to share with you the results.

                  First of all, I removed all power & cable connections, turned the entire speaker upside down for about several days. Then I reconnected the speakers (still in upside down position). To my surprise, the noise was gone. After several rounds of audition, everything seemed to be normal. So I returned the speakers to their normal positions and performed several more rounds of audition, the noise was not heard of again.

                  So as far as the situation shows, the noise is removed by just turning the speaker upside down.

                  I am curious as to what happened (both the problem and the cure). Is it because the cone is out of position mildly (due to sudden surge of current) and the force of gravity is put into work when the speaker is turned upside down and thus the cure? So should we turn the speaker upside down every year or so as a preventive maintenance?

                  Any sharing is welcome. Thanks.

                  Regards,
                  John

                  Comment


                  • #10
                    Re: Noises on C7ES3 Radial driver

                    Originally posted by jttlee View Post
                    Dear TW, sunshine,

                    Over the week I have been carrying out a number of tests and would like to share with you the results.

                    First of all, I removed all power & cable connections, turned the entire speaker upside down for about several days. Then I reconnected the speakers (still in upside down position). To my surprise, the noise was gone. After several rounds of audition, everything seemed to be normal. So I returned the speakers to their normal positions and performed several more rounds of audition, the noise was not heard of again.

                    So as far as the situation shows, the noise is removed by just turning the speaker upside down.

                    I am curious as to what happened (both the problem and the cure). Is it because the cone is out of position mildly (due to sudden surge of current) and the force of gravity is put into work when the speaker is turned upside down and thus the cure? So should we turn the speaker upside down every year or so as a preventive maintenance?

                    Any sharing is welcome. Thanks.

                    Regards,
                    John
                    Dear John,
                    Great that you could heal your speakers. But I'm still wondering what this could have been.
                    I personally don't think that gravity could have any affect on the right centering of the speaker.
                    This would but a question mark on the concept of a speaker itself. All speakers would "age"
                    because of this ...

                    The other idea that comes into my mind is that the internal wiring could have slipped so that the cables touched the membrane. I'm not sure if this is possible. Another idea is that your amp or your cd player had a problem. If this happens again you could doublecheck with another amp.

                    TW

                    Comment


                    • #11
                      Re: Noises on C7ES3 Radial driver

                      Originally posted by sunshine View Post
                      Hi John,

                      I do have a tendency to go loud(claimed by my family members), but i doubt it is due to loudness. I am not electronically sound, but was advised to give the driver a 180 degree turn. So far so good, do not know how loud i play, but at a volume that i enjoy most.

                      If you do plan to turn the driver around, when you unscrew your driver's bolts, try to feel how tight it was tightened and when securing them, do not over tighten it.
                      Dear sunshine,

                      I'd like to know how often you need to turn the driver around.

                      For my case, over the past 2 months, I turned the speaker (instead of the driver) upside down once I encountered the problem. The problem does not occur again with my left speaker but my right speaker keeps on having occasional noise once I return the speaker to normal position.

                      I just raised the case to the HK dealer to follow up. And I am anxious to know whether anybody has similar experience. I am quite sure I only play within a normal level over the past 2 months.

                      Thanks.

                      Regards,
                      John

                      Comment


                      • #12
                        Re: Noises on C7ES3 Radial driver

                        I have had no problem with my ES3 so far, i feel very sorry for the owners with this problem.

                        I learnt the lesson of how easy it is for a user to over drive a pair of harbeth when i was a kid, I blown my father's and he had to had the drivers replaced (it was the TPX drivers).

                        Becuase the harbeth sound is so smooth and doens't distort and you kind of just keep on turning the volumn up and up without knowing the fact its way too loud.

                        i dobut it is the fault of the speakers, it could be the amp clipping and therefore done the damge to the drivers.

                        Comment


                        • #13
                          Re: Noises on C7ES3 Radial driver

                          Originally posted by jttlee View Post
                          Dear sunshine,

                          I'd like to know how often you need to turn the driver around.

                          For my case, over the past 2 months, I turned the speaker (instead of the driver) upside down once I encountered the problem. The problem does not occur again with my left speaker but my right speaker keeps on having occasional noise once I return the speaker to normal position.

                          I just raised the case to the HK dealer to follow up. And I am anxious to know whether anybody has similar experience. I am quite sure I only play within a normal level over the past 2 months.

                          Thanks.

                          Regards,
                          John
                          Hi John,

                          I'd turned the driver only once ,180 degree, since then i do not have that problem and I still play rather loud. Since you'd raised this to your dealer, just wait and see what they have install for you.

                          Sorry to hear that you're still going through this...i wish you luck and hope your dealer can be of good help to you.

                          Cheers,
                          sunshine

                          Comment


                          • #14
                            Re: Rotate woofer through 180 degrees & distributors support

                            So Alan, does this problem indicate overdriving the loudspeaker or is it due to a "natural" sagging of the driver's suspension? I once had speakers with what seems to the same problem - scraping noises that I eliminated by rotating the woofers through 180 degrees (they weren't Harbeths). I remembered talk of "cone sag" from somewhere and decided to try to reverse the sag. It took a few days but the speakers seemed to sound as good as ever after that.

                            Comment


                            • #15
                              Gravity or not?

                              I think that someone on this thread completely dismissed the idea of gravitational pull on the cone so it can't be that then. Or can it? What's important is to consider the distribution of the weights throughout the cone system: the rubber surround (heavy), the cone itself, the voice coil and its braid wires. If you imagine that you have x-ray eyes and could see through the side of the cabinet you'd see that these parts are arranged on a see-saw, pivoted on the corrugated 'spider' (cloth suspension - usually yellow - hidden from view) at the neck of the cone.

                              If you recall from the children's playground, there is a perfect correlation between the child's weight and the distance from the fulcrum (balance point). A child of weight X and distance D from the pivot can be perfectly counterbalanced by child Y also at point D if the children are the same weight. But if one child is weight 2X, then child Y must also be 2Y or he must be two times further away.

                              How does this relate to drive units? Well, the heaviest part of the [surround, cone, coil assembly] is the cone, and especially the surround. The surround is both the heaviest part and a long way from the fulcrum, the spider just under the neck of the cone. The coil, on the other side of the fulcrum is much lighter than the surround, and also much closer to the fulcrum. This means that the centering stability of the entire system depends really upon the quality of the 'spider' and the elimination of grit and particles from the very narrow gap in magnet in which the coil slides. The louder the speaker plays - especially if it is vented in a dusty environment - the greater the danger of grit entering the gap.

                              I can imagine four potential failure mechanisms that could only be positively identified if the unit is surgically dissected ....

                              1) Grit or dirt in the magnetic gap (the tunnel in which the voice coil moves)

                              2) Overload of voice coil at some time during the speaker's life which caused the varnish on the voice coil wire to bubble and/or the wire itself to deform and this scratches on the inside of the gap

                              3) Some softening or weakening of the spider material causing the unit to be more susceptible to gravity

                              4) Overload at some time which caused the voice coil former to bash against the inside of the magnet back-plate (hidden) and has put a small crease into the aluminium former.

                              If the unit is returned to us here we can give you a positive analysis and provide you with a video of the dissection, as per our ISO9001 mandate.
                              Alan A. Shaw
                              Designer, owner
                              Harbeth Audio UK

                              Comment

                              Working...
                              X