Page 3 of 3 FirstFirst 123
Results 41 to 58 of 58

Thread: Modifying your Harbeths - real benefits or not?

  1. #41
    Join Date
    Feb 2006
    Location
    Malaysia/Singapore
    Posts
    435

    Default

    Quote Originally Posted by kittykat View Post
    If someone has bought something well made and beautiful (like Harbeths) for what it was (or even married someone), sit back, admire, feel grateful, lucky and proud. Your speakers (or partner) will automatically sound better (and be more beautiful). I guarantee you.
    I like this very much. Appreciate.
    "Bath in Music"

  2. #42
    Join Date
    Dec 2007
    Location
    Singapore
    Posts
    160

    Default

    Me too... thanks for reminding... as time goes by we tend to forget.. especially... when we are seaching for the "ultimate" in HI-Fi. If you watch youtube, Greek Audiophile you will know what i mean

  3. #43
    Join Date
    Mar 2011
    Location
    USA
    Posts
    35

    Default

    "If someone has bought something well made and beautiful (like Harbeths) for what it was (or even married someone), sit back, admire, feel grateful, lucky and proud. Your speakers (or partner) will automatically sound better (and be more beautiful). I guarantee you."

    The speakers will sound better than what? It seems that you're suggesting that pride of ownership results in improved sonics. This is the placebo effect; the very same argument that those of you who don't hear differences in cables or electronics use to discredit those of us who do.

  4. #44
    Join Date
    Nov 2010
    Location
    Philippines
    Posts
    47

    Default

    He merely said that if you are happy with what you have, it will please you better, you will enjoy it more and it will sound better since you are happy. But if you wish to redesign something that is already well designed to seek perfection... I don't think you will ever find it. try to enjoy life, a better outlook will make you happier... that is guranteed (but please don't ask me for a written document with a letterhead) :D

  5. #45
    Join Date
    Jun 2009
    Location
    Canada
    Posts
    913

    Default

    To Diminish:

    I agree with what others have said. Since you mention the "placebo effect", don't forget that it can work the other way as well. How much of the "improvement" you are hearing from your tweak is as a result of a meaningful change to the physical property of your loudspeakers, and how much is due to a sense that you personally have done something to affect their sound? Can you really separate the two?

    I think the urge to tinker is understandable - it gives one the pleasant feeling of agency, of having done something oneself, of not being just a consumer, but also a participant and co-creator of the experience. It's a nice psychological feeling to have.

    But I think that it's also an illusion, at least when it comes to something as complex as a well-designed and well-engineered loudspeaker. I know very little about loudspeaker design, but I know something about expertise. And real expertise - in any field - is something one works long and hard to acquire, and it needs to be recognized and respected where it exists. Sometimes it's hard to know what we don't know, but it can be crucial to recognize that we don't actually know. That doesn't mean one can't ask questions, but likewise one needs to have the humility to recognize that one's own knowledge isn't on the same level as that of an expert.

    When it comes to a Harbeth product, I am content to derive my sense of "participation" from the knowledge that I have made a very good choice.

  6. #46
    Join Date
    Feb 2006
    Location
    United States
    Posts
    53

    Default

    EricW,

    This is an extremely good example of what I've experienced many times, with many products, and on many different levels. Thanks for taking the time and making this a wonderful forum.

    John

  7. #47
    Join Date
    Sep 2009
    Location
    Malaysia
    Posts
    508

    Default Can we do better than years of research?

    Quote Originally Posted by Diminish View Post
    ....A Sony 5400ES SACD player that receives the Modwright Ultimate Truth modifications sounds much better than the bare stock Sony..
    Dimmish made a very pertinent point about the modified SACD player. Another example would be F1 cars where even after spending millions or billions Toyota wasn't able to produce a competitive car for winning the races but there were teams (non car manufacturers but specializes in some aspect of car engine modification) that used Toyota's engines and managed to make their cars to outperform Toyota. At least to my opinion, it is possible for one to make further improvements to an already perfect product but this takes another equally competent engineers backed with solid engineering knowledge which we as ordinary customers do not usually possess. Under such circumstances, it is possible for anyone who throws one or two research papers or some measurements to play on our ever presence psychosis behaviour and induce us into believing something that is non-existent.

    Now coming back to the washers, could it really improve the sound? If so why BBC which had some of the best brains in audio engineering did not discover such simple devices to improve their products? Why did they waste extensive years of research to produce Radial drivers when a simple washer could do the job to improve the previous pp drivers?

    For the past couple of weeks I was busy trying to establish to myself if speakers stands would improve the sound of my SHL5. Finally, I just came to one simple conclusion that I can’t be absolutely sure if damping, coupling, decoupling or sand bagging the stand ever made any difference to the sound. Next what I did was to introduce additional vibration to the cabinets by leaving a small battery operated motor running (found in toys about the 2cm x 1cm dimension) on the top of speaker cabinet surface so that it rattles the cabinet gently (like you are tapping your fingers on the cabinets).

    I can safely say no one (four people) could ever tell if the additional motor sound actually deteriorated the sound. No one could and none of my hi-if friends interested to find out why so much vibration, which was more than the vibration of my speaker stand didn’t cloud or colours the sound?

    To my mind, if so much additional vibration couldn’t affect the sound than there is no way small things like spikes or heavy stands or a washer could ever make any difference to the sound. In the case of a driver, the biggest area where the refracted energy that somehow capable of reaching the cones must cross the rubber surround which holds the cones suspended and that energy would be a tiny fraction of the immediate problem for the cones which comes to them through the very air that it moves to create the sound.

    One important thing I learned in this forum is to not to rely on our audio memory to judge sound. If anyone has taken the absolute pitch test in the audiocheck link posted here by our reader in another thread, I realized my audio memory is not even the standard 20 seconds but more like 5 to 10 seconds! So if you are unable to make simultaneous switching to do AB test to hear small differences in sound then it is not worth the time and effort.

    ST

  8. #48
    Join Date
    Jan 2006
    Location
    South of England, UK
    Posts
    4,383

    Default A battery operated auto-knock tester ...

    Quote Originally Posted by STHLS5 View Post
    ... Next what I did was to introduce additional vibration to the cabinets by leaving a small battery operated motor running (found in toys about the 2cm x 1cm dimension) on the top of speaker cabinet surface so that it rattles the cabinet gently (like you are tapping your fingers on the cabinets).

    I can safely say no one (four people) could ever tell if the additional motor sound actually deteriorated the sound. No one could and none of my hi-if friends interested to find out why so much vibration, which was more than the vibration of my speaker stand didnít cloud or colours the sound? ...
    One important thing I learned in this forum is to not to rely on our audio memory to judge sound.... I realized my audio memory is not even the standard 20 seconds but more like 5 to 10 seconds! So if you are unable to make simultaneous switching to do AB test to hear small differences in sound then it is not worth the time and effort.
    This experience is made all the more valuable because you conceived an appropriate experiment, you used simple gadgets that everyone can understand and you rolled up your sleeves and actually bothered to do it. I congratulate you for your intellectual aptitude. How could anyone disagree with your findings? Many thanks.
    Alan A. Shaw
    Designer, owner
    Harbeth Audio UK

  9. #49
    Join Date
    Mar 2011
    Location
    USA
    Posts
    35

    Default

    "How could anyone disagree with your findings?" Easily enough, actually: the dergree to which the homemade vibrator effects the sound of the speaker would be a function of the intensity of the sound played through the speaker, the vibrational energy transmitted directly into the cabinet, and the sound radiated into the acoustic environment by the motor. Depending on the frequency of this sound it will interfere with the [presumeably music] played through the loudspeaker. The intensity of the vibrational energy from the motor being assumed constant, the control variable would then be the playback volume of the music through the speakers. Was this held constant throughout the evaluation? Does this experiment closely approximate any real world vibrational interference that the speaker would be likely to encounter? What is the resonant frequency of the cabinet, it's elastic modulus? At what frequency does the motor vibrate, it's amplitude? What measures have been taken to control for electromagnetic damping from the motor itself? Are the results replicable?

    So now we have that a placing a vibrator a-top the cabinet of a Harbeth speaker does not effect it's sound, cables and electronics do not effect the sound, in fact, in another post, it is stated that you could cut through the Radial driver and THAT would have little effect on the sound! How is it, then, that placing a decoupling washer on the bolt that holds the basket in place is such a fatal flaw?

  10. #50
    Join Date
    Sep 2007
    Location
    England
    Posts
    250

    Default Harbeth Warranty and how to nullify it

    To answer your question:

    Yes, if a customer opens our factory-made and ISO certified speaker then the factory Warranty cannot be assured. Remedial work in-warranty can only be undertaken by an Authorised Harbeth agent. This is a universal fact applying to the opening-up of all manufactured products, not just Harbeth.

    As we have already told you this manufacturers-run Harbeth User Group does not exist to promote unauthorised DIY redesign of our products when we have a full order book for those same products. Maybe there are other outlets on the internet for such contributions but not here. We will not permit discussion of modifications of any part of the internal construction of a Harbeth speaker system on this forum simply because of the potential impact on the Warranty we offer the first owner*. We stand by our Warranty providing that the user plays-fair and does not attempt DIY modifications.

    * There are certain Terms and Conditions relating to our Warranty.

  11. #51
    Join Date
    Sep 2009
    Location
    Malaysia
    Posts
    508

    Default

    Quote Originally Posted by Diminish View Post
    "?..............Depending on the frequency of this sound it will interfere with the [presumeably music] played through the loudspeaker. The intensity of the vibrational energy from the motor being assumed constant, the control variable would then be the playback volume of the music through the speakers. Was this held constant throughout the evaluation? Does this experiment closely approximate any real world vibrational interference that the speaker would be likely to encounter? What is the resonant frequency of the cabinet, it's elastic modulus? At what frequency does the motor vibrate, it's amplitude? What measures have been taken to control for electromagnetic damping from the motor itself? Are the results replicable?.......flaw?
    Well....you got a point about the constant vibration of the motor. Would you agree if I were to place another set of drivers or woofer on the top of the cabinet and the volume of the driver is controlled independently through a resistor so that it is not audible where I sit? Shouldn't then the vibrational effect be the same?

    I can't wait to do the experiment and would appreciate your contribution to improve the experiment. Please PM me if you have any. Thanks

    ST

    p.s. I am aware that this forum does not encourage discussion of cables, interconnects, spikes or similar tweaks so I will just confine to the facts why it is humanly impossible to judge micro incremental improvements by tweaks.

    In a thesis submitted by the department of Mechanical engineering to determine noise control found out that a mere shift of 2 mm of the microphones changes the reading of 600Hz values as much as 0.6 to 0.8dB and as much as 20dB when under a different configuration.

    When we apply the same to our ears we should know that it is humanly impossible for someone to sit still at the exact location even for a few minutes. As time goes by. we tend to relax and then our body may lean deeper to the couch, our head may be slanting a few degrees and our focus too would have changed. Not to mention that our room temperature varies which affects the sound. The air conditioner would have brought the temperature down by 1 Celcius or it could have gone 1 Celcius up due to heat from the amplifier and our body.

    Taking the example of putting an object (washers) in the cabinet, wouldn't that too change the volume of the cabinet air by about 640 cubic millimeters affects the sound? With so much variables to account for how could we ever able to hear micro details difference when it is almost impossible to tell the 1dB difference even with reference?

  12. #52
    Join Date
    Jun 2009
    Location
    Canada
    Posts
    913

    Default

    The simple fact is this: if the tweak under discussion made a real difference to the sound of a pair of Harbeths, one of two things would follow:

    (1) It's a design flaw/deficiency not to have incorporated such an inexpensive way of making an improvement to the sound {at the time of manufacture}; or

    (2) It's an economic choice by Harbeth not to pay for the improvement.

    Now, the question is, is either likely?

    Given what we know about the cost of producing Harbeth speakers (expensive cabinetry, expensive drivers), it seems unlikely that the cost of a washer would impact Harbeth's decision-making process.

    So if we rule out possibility (2), that leaves (1), i.e. the possibility that the design is flawed, in the sense that a simple and cost-effective improvement has simply been overlooked. Let's grant that it's a possibility and ask how likely it is. Is it likely that a company that cares enough about their design to actually invent and use a unique and proprietary cone material, at considerable cost, would overlook a minor improvement that paid real dividends in improving the sound? Possible. But very unlikely. (To say nothing of the deep research legacy represented by the BBC background.)

    So if we eliminate (1) and (2), only one possibility remains: the design has been thought out and optimized to a point that minor DIY tweaks likely have no positive impact on sound quality, may well have a negative impact, and in any event risk voiding the warranty.

    Now if a valid listening test could repeatedly and reliably demonstrate differences, that would be one thing. But until such test has been performed, I think scepticism is justified.

  13. #53
    Join Date
    May 2009
    Location
    England
    Posts
    856

    Default

    Over the years I have tried numerous gizmos which are placed on or stuck on speaker cabinets. They all claim to improve the sound and some have cost many hundreds of Pounds. To my knowledge, they all relied on something in their structure resonating with the vibrations of the speaker cabinet.

    So far, out of those I have tried, some make a small 'difference' to the sound, the others had no audible effect. Of those that produced audible changes, the result was a very slight 'difference' and never an outright improvement. I believe I still have a few in a box somewhere but have never had the slightest inclination to use them again.

    Keep it simple and save your money.

  14. #54
    Join Date
    Feb 2013
    Location
    USA
    Posts
    42

    Default Subwoofer?

    "What else could one possibly need...." etc? What about a sub woofer? The smaller Harbeth goes down to 75 Hz, correct? So, what about the bass? No bass? It just makes sense to add a sub woofer, right? Has anyone tried that yet? What were the results? Thanks, John

  15. #55
    Join Date
    Jan 2006
    Location
    South of England, UK
    Posts
    4,383

    Default Interpreting bass specifications

    Quote Originally Posted by boland7214 View Post
    "What else could one possibly need...." etc? What about a sub woofer? The smaller Harbeth goes down to 75 Hz, correct? So, what about the bass? No bass? It just makes sense to add a sub woofer, right? Has anyone tried that yet? What were the results? Thanks, John
    A possible misreading of the specifications?

    When a speaker quotes a specification something like "Frequency response: 75Hz to 20kHz" it does not mean or imply in any way that the bass range stops dead at 75Hz. It doesn't mean that a note of 74Hz, 60Hz or 44Hz is not reproduced. It does mean that there is a progressive fading-out in measured and perceived loudness with diminishing frequency and that, in a well defined specification, from some arbitrary middle range frequency where the loudspeaker is presumed to be flat, that the bass response is x dBs below that loudness at a certain low note.

    So, a proper specification that has some meaning would be something like: "Frequency response: 75Hz to 20kHz minus 3dB". That would mean that, to use your example of 75Hz and mine of -3dB, that the response is three dB down at 75Hz, three and a little bit more down at 70Hz and perhaps five or six dB down at 60Hz. The exact relationship between falling frequency and the number of dBs that the loudness of the bass has diminished is described as the bass roll-off and the gradient of that roll off will vary from speaker model to speaker model based on factors such as diameter of driver/box volume/vented or not/bass tuning and so on.

    The trick is to have enough controls on the sub electronics to blend-in the gradient of contribution of the sub with falling frequency to exactly match the gradient and loudness of the fade-out in the main speaker's energy. If you can closely match these two audio sources into a seamless whole you have achieved big-speaker bass from small speakers plus sub.
    Alan A. Shaw
    Designer, owner
    Harbeth Audio UK

  16. #56
    Join Date
    Jul 2012
    Location
    England
    Posts
    65

    Default The secret of blending a sub with a main speaker

    Quote Originally Posted by A.S. View Post
    A possible misreading of the specifications?

    When a speaker quotes a specification something like "Frequency response: 75Hz to 20kHz" it does not mean or imply in any way that the bass range stops dead at 75Hz. It doesn't mean that a note of 74Hz, 60Hz or 44Hz is not reproduced. It does mean that there is a progressive fading-out in measured and perceived loudness with diminishing frequency and that, in a well defined specification, from some arbitrary middle range frequency where the loudspeaker is presumed to be flat, that the bass response is x dBs below that loudness at a certain low note.

    So, a proper specification that has some meaning would be something like: "Frequency response: 75Hz to 20kHz minus 3dB". That would mean that, to use your example of 75Hz and mine of -3dB, that the response is three dB down at 75Hz, three and a little bit more down at 70Hz and perhaps five or six dB down at 60Hz. The exact relationship between falling frequency and the number of dBs that the loudness of the bass has diminished is described as the bass roll-off and the gradient of that roll off will vary from speaker model to speaker model based on factors such as diameter of driver/box volume/vented or not/bass tuning and so on.

    The trick is to have enough controls on the sub electronics to blend-in the gradient of contribution of the sub with frequency to exactly match the gradient and loudness of the fade-out in the main speaker's energy. If you can closely match these two audio sources into a seamless whole you have achieved big-speaker bass from small speakers plus sub.
    Thank you Alan, first time I read this information ........................ i even understand it!
    So that is what you did with my 30.1's

  17. #57
    Join Date
    Aug 2009
    Location
    United States
    Posts
    73

    Default ... and interpreting a subwoofer user's guide ...

    Quote Originally Posted by A.S. View Post
    A possible misreading of the specifications?
    ....The trick is to have enough controls on the sub electronics to blend-in the gradient of contribution of the sub with frequency to exactly match the gradient and loudness of the fade-out in the main speaker's energy. If you can closely match these two audio sources into a seamless whole you have achieved big-speaker bass from small speakers plus sub.
    Alan with typical clarity described that significant requirement.

    Below is an extract from my REL subwoofer manual. After following the manufacturer's instructions for determining physical location, I then calibrated the crossover and level settings per instructions. Have underscored what Alan corroborated.
    --------------------------------------------------------------------------------------------------------------------------------------
    Crossover and Level Settings:

    To determine the crossover point, take the volume of the REL (using the HI/LO Level control) all the way down, and put the crossover to 25 Hz. At this point, bring the REL’s volume back up slowly to the point where you have achieved a subtle balance, i.e. the point at which you can hear the REL even with the main speakers playing. Now, bring the crossover point up until it is obviously too high; at this point bring it down to the appropriate lower setting. For all intents and purposes, this is the correct crossover point. Once this stage has been reached, subtle changes to volume and crossover can be accomplished to provide the last bit of complete and seamless integration. With that, set-up is complete.

    Hint: There may be a tendency to set the crossover point too high and the volume of the Sub-Bass System too low when first learning how to integrate a REL with the system, the fear being one of overwhelming the main speakers with bass. But in doing so, the resulting set-up will be lacking in bass depth and dynamics. The proper crossover point and volume setting will increase overall dynamics, allow for extended bass frequencies, and improve soundstage properties. Note, volume must be adjusted in conjunction with crossover changes. In general, when selecting a lower crossover point, more volume may need to be applied.

    Addendum
    Have setup a REL T9 subwoofer with my Harbeth C-7.

    A really good sub will integrate so seamlessly into your system that it will not draw attention to itself. You'll should have the added foundation of the bass, and should experience added ambience in your soundstage. One should not hear the subwoofer as a separate entity, and the bass should sound tuneful and integrated with the rest of the music. Seamless integration is one of the hardest things to design into a sub and is often overlooked by first-time subwoofer buyers.

  18. #58
    Join Date
    Jun 2011
    Location
    Belgium
    Posts
    115

    Default Sealed boxes, gentle roll-off

    Be sure to highpass the P3's when using a subwoofer, otherwise you lose the benefit of increased power handling (with respect to the specs given by Harbeth in terms of power handling of course). I've used my system like this in the past and it worked superbly, giving the impression of a much larger system.

    On the other hand, the P3's are not at all shy on their own in the low register, in their current position in my own room, they are pretty much flat to 50hz. They're the mostwonderful versatile little speakers.

    Sealed speakers have a gentle natural rolloff, proper placement in a room, can extend the bass much deeper than outside measurements will tell you.

Page 3 of 3 FirstFirst 123

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •