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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
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The last words on audio amplifiers [Jan. 2015]

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  • The last words on audio amplifiers [Jan. 2015]

    First post. My original plan was to upgrade my {small Harbeth's} to the {bigger Harbeths} not for any other reason than because I could. I love the way my speakers sound but it would be nice to have something even better. I auditioned the --- and was pretty sold that this was the way to go. By chance I borrowed from my brother his {amp} since he wasn't using it and I replaced my Audiolab 8200a. To me the sound difference was more than I could have ever hoped for. The new amp makes my speakers sing like I have never heard before. The idea of a speaker upgrade is out the window now. My original speakers sound great.

    Sure there will be the naysayers, which there are plenty, say the amp won't change the sound dramatically but I will respectfully disagree. The {amp} has better specs than the Audiolab and it shows. Some might say having 250 watts of power is overkill for a bookshelf speaker and I agree it is, it doesn't mean I have to use all that power. I live in a small condo in downtown Toronto, the speakers fill it the room quite nicely.

    I like that I have replaced my Audiolab M-DAC and 8200a with one integrated amplifier. The {amp} being a direct digital amp as I like the simpler look. My music source is just a plain Windows netbook using iTunes. Everything works, I like it, I am a happy listener.

  • #2
    Originally posted by blakcloud View Post
    First post. My original plan was to upgrade my --- to the --- not for any other reason than because I could. I love the way my speakers sound but it would be nice to have something even better. I auditioned the --- and was pretty sold that this was the way to go. By chance I borrowed from my brother his ...
    The general consensus regarding amps is that if level matched they will sound the same as long as you play within the limits of the least powerful unit, that is not the same as saying all amps will do the same with a given pair of loudspeakers. You are most likely reaping the benefits of the extra power of the NAD, power allows to speakers to play with less distortion.

    Anecdotally in my case, a while ago I got a new amplifier, it has 100W vs my old amps 30W, I felt it was a revelation and sounded clearly better than my original one, for sure I can play louder with less distortion but I'm pretty sure in listening to that new amp carefully I was merely listening to my music more carefully and felt I was hearing more, I was simply taking more notice, and now if I compare both amps at matched levels I cannot tell one from the other. Right now I am using a 2 channel mixer and a pro power amp (total cost $600) for the convenience of features, the amp runs 280W into 8 Ohms, it sounds fine and the speakers I currently have play very cleanly indeed.

    Power though is always a good thing, in a sense with the new amp you are optimizing your P3's, giving them as much juice as they can handle, I'm sure they sound amazing.
    Getting to know my C7ES3

    Comment


    • #3
      More amp power means L O U D E R - Caution.

      Originally posted by acroyear View Post
      The general consensus regarding amps is that if level matched they will sound the same as long as you play within the limits of the least powerful unit, that is not the same as saying all amps will do the same with a given pair of loudspeakers. You are most likely reaping the benefits of the extra power....
      Again gentlemen, can I implore you to take on board the facts, which have been laid out here in numerous threads covering amplifiers and human hearing. They are unarguably the objective truth, and you ignore them at your financial peril!

      To state, briefly, yet again: it is absolutely meaningless to hook up two amplifiers, regardless of brand, technology, shape, size, colour or price in the absence of knowledge of their internal GAIN from input to output and then draw any meaningful conclusions about their subjective sonic performance. And when I say meaningless, I honestly do mean meaningless and it's ten times worse to them report that in a way which could suck others into making the same error.

      And the reason, yet again, is this: if one amp is hugely more powerful than the other (which is claimed here) for any given rotation of the volume control, the output signal at the speaker terminals will be, obviously (?) LOUDER. And that's what you are hearing. The music is LOUDER, the sensation in your brain is DIFFERENT and your subjective experience is ALTERED. This then leads to the unjustified and almost certainly entirely false logical error that one amp has sonic superior over the other, because that is what the different SENSATION in your brain fools you into asserting. But that is, all previous researchers have concluded, a logical and factual fallacy exposed by carefully controlling the loudness so that it exactly matches.

      Corollary: use some basic test equipment to establish a common voltage to the loudspeaker terminals applicable to both amp A and B, which will result from radically different rotation of the volume controls*, and you will have the greatest difficulty detecting whether you are listening to amp A or B. That I guarantee. And I have offered a pair of M40.1s to anyone who can disprove that, but nobody has taken up the challenge.

      *Example: to deliver exactly the same voltage to the speakers, hence the same loudness at the ear, one amp may have the volume control set at, say, 2 o'clock, half rotated, and the other at 9 o'clock, barely on. Could this be guessed without test equipment: not a hope.
      Alan A. Shaw
      Designer, owner
      Harbeth Audio UK

      Comment


      • #4
        The danger of misinterpreting 'loudness'

        This confusion in our brain between loudness and our subjective interpretation of sonic attributes that leads to is not just a characteristic of the ear/brain. The eye/brain (or indeed taste/brain, touch/brain) have exactly the same issues. The reason is that our senses generate electrical activity in response to stimulus, and our brain receives and interprets those electrical impulse. Note that I said impulses. Impulses are not continuous signals. They are bursts of individual electrical pulses, and when there is no stimulus, the trigger is removed and the impulses cease. Close your eyes and the optic nerve ceases to send electrical pulses to the brain. Step into an anechoic chamber, and your ears cease to send electrical impulses to the brain.

        The problem we have is that when a stimulus becomes sonically louder more pulses are sent to the brain. When we observe different colours, more pulses are sent. The senses and brain are not at all analogue: they are wholly digital.

        Take two pictures, one is optically 'louder' than the other. Fundamentally they are absolutely identical except that one is a bit 'louder' - it has more overall energy. See how skewed your mental impression is when loudness, the energy impacting on our senses, is altered?

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        Alan A. Shaw
        Designer, owner
        Harbeth Audio UK

        Comment


        • #5
          The game is over

          Alan.

          I for one have jumped off the hifi train, in establishing that I cannot differentiate between a $1300 barebones trendy class D x valve amp (when I bought it I wasn't even aware that valves were supposed to give a sonic signature) and a 2 channel mixer/pro power amp at half the cost.

          I have popped the feature filled latter into my audio set up, the hifi amp will be traded vs a pair of loudspeakers. I will still look for a more 'front room and spouse friendly' feature filled preamp of sorts in the meantime to swap out the mixer.

          Had I not joined HUG and been introduced to the notion that amps do not have sonic signatures (and reading many articles aside: abx tests giving no positive identifications despite significant cost differences) I might well have been still looking at electronics and player and cables......I really wish I had found Audio Critic 25 years ago!
          Getting to know my C7ES3

          Comment


          • #6
            Flawed brains?

            And the human ear is so unreliable and insensitive that it cannot even realise that there is a doubling of loudness!!!

            In that sense, the ears must be worse than the eyes which can at least see the difference in "colour loudness" in the pictures.

            The greatest irony though is that in the end you will have to rely on those unreliable, insensitive ears to enjoy the music based on the "flawed subjective interpretation" by your brain.

            (Reading many posts in this forum begs the question - why bother at all? Get the cheapest possible speakers and connect them to the cheapest laptop you can get - you will still get the same electrons moving through the cables)

            All the best.

            Comment


            • #7
              Buyer's remorse?

              Originally posted by SChat View Post
              And the human ear is so unreliable and insensitive that it cannot even realise that there is a doubling of loudness. In that sense, the ears must be worse than the eyes which can at least see the difference in "colour loudness" in the pictures.

              The greatest irony though is that in the end you will have to rely on those unreliable, insensitive ears to enjoy the music based on the "flawed subjective interpretation" by your brain.
              Enjoying recorded music does not mandate exotic, expensive audio hardware. I can get almost total satisfaction from a transistor radio quietly singing away somewhere in the room behind me when I am typing (this, for example) and when I cannot give, or do not want to give my fullest attention to music.

              The issue surely is - and I really do hope that this is fully grasped - that if you are the sort of person with deep pockets and a personality that thrives on dissatisfaction and buyer's remorse, then by all means take as a call to action posts that make well intentioned but fatally flawed wholly unsubstantiated and unsubstantiatable claims about the sonics of audio electronics: be my guest. If however, like me, living in the real world with limited funds to invest, you actually place true value for money and long-running satisfaction with the music as the first, second and only goal in an audio life, then get a grip on reality and appreciate how the fallibility of your human senses can all too easily trap you in a lifetime of audio equipment churn. Or even misery. And my sad observation is that those most vulnerable to audio marketing's seven veils are often the least able to afford the expenditure - the most vulnerable end of the audiophile ladder.

              Unless there is a basic appreciation of how our senses are tickled and teased, consumers have handed responsibility over their wallet to marketeers, and I think that is a miserable state to find oneself in. No long term good can come of that.
              Alan A. Shaw
              Designer, owner
              Harbeth Audio UK

              Comment


              • #8
                The reality of human hearing

                Plug your computer into your amp and head to: http://www.audiocheck.net/ (or make a CD from the downloadable files)

                So, when you find yourself comparing devices with respective SNR of 97 and 103dB you can remind yourself you couldn't possibly hear the difference.

                From my visits to this site, I have discovered that my upper limit of hearing is 16-17KHz, and I can't make out a difference in volume of less than 0.5dB, and even then only just. The test with a 0.3dB difference was too close to call.

                Also found out that you also have all the dynamic range you could ever need for home listening without resorting to audio formats over 16bit...

                Interesting stuff.

                Comment


                • #9
                  Practical audio specifications

                  Originally posted by mattw View Post

                  Interesting stuff.

                  Indeed it is. I was a bit chagrined to find that my own upper-frequency limit is about 13 kHz, though given my age and my youthful exposure to copious amounts of loud amplified live music, that's probably not surprising.

                  I'm not sure that the "blind" noise-based frequency tests are that valid, though, just because of the time gap between samples. It's not clear whether they're testing HF acuity or audio memory (and we know how reliable that is). They actually make the point quite well that you really do need an instantaneous A/B switchover to be able to compare accurately.

                  With respect to the levels, I found that my ear was far more sensitive to an increase in level (easy to hear 0.2 dB, and thought I could even hear 0.1 dB) than to a drop in level, where I could only just make out an 0.5 dB drop, and certainly nothing less than that. Whether that's just me, or a more general principle, I don't know. But again, the blind test doesn't distinguish between level increases and level drops in the testing, so it's hard to tell.

                  What's clear is that nothing anything in the audio equipment chain does above, say, 15 kHz (to be generous and give myself a margin) is likely to affect my enjoyment of music in the slightest.

                  Comment


                  • #10
                    I don't like it here in HUG

                    Sorry Alan, I won't drink your Kool-Aid. I have perusing this board for a while and two thing are abundantly clear. In your mind you are always right when it comes to amplifiers and the hundreds of manufacturers and engineers of these amplifiers are always wrong. You spew the same vitriol on almost every thread and if you don't the secret moderator adds his comments below the original thread.

                    This isn't a board for discussion for Harbeth Users, this is an Alan Shaw blog at best. Two great things did come of this, first, I won't ever post again and please delete my account. Second I get to voice my displeasure with my well filled wallet. I never buy products from people, or companies I don't like and you sir, I don't like. Then again I am writing to thin air as Mr. Secret Moderator will certainly delete this long before anyone gets to read it.

                    Comment


                    • #11
                      Interpretations magic

                      Originally posted by SChat View Post
                      The greatest irony though is that in the end you will have to rely on those unreliable, insensitive ears to enjoy the music based on the "flawed subjective interpretation" by your brain. All the best.
                      I believe that it is much more of the latter. And that interpretation magic can be a friend if you let it, filling in the missing stuff in any home audio experience. If that wasn't the case, anyone that has experienced the enjoyment of a live gig could never settle for anything less.

                      Comment


                      • #12
                        Originally posted by blakcloud View Post
                        Sorry Alan, I won't drink your Kool-Aid. I have perusing this board for a while and two thing are abundantly clear. In your mind you are always right when it comes to amplifiers and the hundreds of manufacturers and engineers of these amplifiers are always wrong. You spew the same vitriol on almost every thread and if you don't the secret moderator adds his comments below the original thread.

                        This isn't a board for discussion for Harbeth Users, this is an Alan Shaw blog at best. Two great things did come of this, first, I won't ever post again and please delete my account. Second I get to voice my displeasure with my well filled wallet. I never buy products from people, or companies I don't like and you sir, I don't like. Then again I am writing to thin air as Mr. Secret Moderator will certainly delete this long before anyone gets to read it.
                        I was tipped off in a private message that this was a likely outcome of this contribution from North America and so it seems.

                        It's absolutely ludicrous to make a contribution here that compares a Ferrari with a Fiat 500 without any attempt to equalise the power so that both are operating comfortably within a common (small) range before listening. Just plain daft.

                        I have consistently drawn attention to the sad fact that there has never been, to the best of my knowledge, a published comparison of audio amps operated under common, controlled conditions - back to the QUAD tests - in which careful observers have been able to replicate the claimed huge differences between amps by listening alone. The first and foremost requirement of control is loudness, level, at the listener's ear and attempting to compare a 250W amp with a 50W amp, where the bigger amp is so obviously much louder, is pure folly unless it is turned right down to match the loudness of the smaller amp. That needs some test equipment to align exactly.

                        I have also consistently said that contributors should not believe me about audio matters without checking for themselves since I am far from a disassociated individual and I've always encouraged readers to undertake heir own private reasoning, research and experimentation. The educational barriers to entry into the audio arena are nil: good ears, an open mind and a little reading about our senses are all that you need to unlock the mysteries of audio. The HUG seems to have found it's own niche in a sea of audio misconceptions and misinformation, and I don't doubt that it can make very uncomfortable reading for many. That's the problem with exposing the truth.

                        I am wholly unmoved by personal attack because when I have taken the trouble to make controlled comparisons, I can only repeat the conclusions of previous and far better qualified researchers. Readers here have been guided here as to how to set up their own controlled comparisons, and that equally applies to manufacturers and their marketing agents including journalists. There is a persistent disinterest in facing reality for obvious vested commercial interests. Many mortgage depend on a perpetual disinclination to face facts. Of course, it remains a possibility that further careful tests will expose genuine differences in new generations of equipment, and if those tests are truly repeatable, a great service has been provided to the audio public in weeding out genuine advances in sonic technology from marketing blarney.

                        The amplifier subject is now closed on HUG. Our position that any competent amp will work just fine with Harbeth's, and that really is all readers need to know. These last few posts will be blended into more appropriate existing threads and this thread deleted.
                        Alan A. Shaw
                        Designer, owner
                        Harbeth Audio UK

                        Comment


                        • #13
                          "Prove it, mate!"

                          Thanks to our contributor for the prompting, but there is the perfect opportunity to allow the public to hear Harbeth speaker at Bristol next month over two extremes of amplification.

                          As you know, I believe that there are many more relevant and important factors in choosing an audio amplifier than fabled sound quality. Factors that I would put first are brand reputation for durability and after care, price, styling, shape, features, running cost, power output and so on. Real features, really worth paying for.

                          Good news: the Pulse amplifier is now on special offer at an amazing GBP69.95 (about $105) plus sales tax, so I've ordered one just now for delivery next week. I'll bring along the excellent remote control A-B switcher box which can be used 'backwards' to switch two amplifiers into one pair of speakers (rather than two pairs of speakers from one amplifier) and unannounced, we'll cycle between our luxury German amplifier and the Pulse throughout the day without disclosing which. This is not intended to be a gladiatorial test distracting from what we are there to promote - Harbeth speakers - but to prove that Harbeths will work well with a very wide range of amplifiers even in a 30:1 price ratio. That said, there is negligible pride of ownership in a $100 amp mass produced in a soulless factory, and oodles of pleasure to own a hand crafted German amp, thoroughly tested and built to last.

                          Come along and hear for yourself I'm half tempted to say that if you come to the room ten times and correctly identify which amp you are hearing you can take away the speakers and Pulse amp FOC at the end of the show!*

                          "Can't be fairer than that mate!"

                          >

                          {*Brilliant marketing move. Would save us couriering the speakers back to HAL. -Mod2
                          }
                          Attached Files
                          Alan A. Shaw
                          Designer, owner
                          Harbeth Audio UK

                          Comment


                          • #14
                            Breakdown?

                            Originally posted by A.S. View Post
                            Good news: the Pulse amplifier is now on special offer at an amazing GBP69.95 (about $105) plus sales tax, so I've ordered one just now for delivery next week.
                            How much would you worry about speaker damage due to some kind of catastrophic amp failure in this case? I suppose this is a risk common to all amps, but ought to be mitigated in some that may consequently cost more than this one. One reason to not expose expensive speakers to something like this one?

                            Comment


                            • #15
                              Contingency plan

                              Originally posted by Kumar Kane View Post
                              How much would you worry about speaker damage due to some kind of catastrophic amp failure in this case? I suppose this is a risk common to all amps, but ought to be mitigated in some that may consequently cost more than this one. One reason to not expose expensive speakers to something like this one?
                              Very fair point. I've used the earlier version for years and it's never missed a beat. Maybe we should have a backup pair of speakers?
                              Alan A. Shaw
                              Designer, owner
                              Harbeth Audio UK

                              Comment

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