"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 may be for you. Either way, welcome to the world of Harbeth!"

Feb. 2018
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Group-think: What would a Harbeth amplifier look and feel like?

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  • Group-think: What would a Harbeth amplifier look and feel like?

    Munich 2015 introduced us to the world of modern amplifiers, which combine advanced networking/streaming (and similar) facilities into one box. Tube amps, so prominent at the show in previous years were hard to find; the market has truly changed.

    We claim no particular insight into what the modern consumer expects from his audio amp other than the basic facilities of adequatre power and sensible input sensitivities to match the sources properly. What is clear is that if even one up-and-coming feature is accidentally omitted from the design due to ignorance of market trends, the resulting product could struggle. Even amp designers are sometimes too close to their technical work to see and sense the changing consumer environment around them.

    We as a group can use the next four days to assemble a specification for the VITAL features for such an amp, the DESIRABLE features, and the OPTIONAL (perhaps plug-in after-market) features. Three very clearly defined categories.

    Take, for example, a phono stage, inside the amp case. How many would consider that a vital feature or only an optional one? If I'd invested in a fancy phono head amp, it would be a feature that I'd not need or want to pay for again.

    I think we all know that the power reserve must be generous - no need to even dicuss that - that's assumed and available. What we're curious about is the digital side of the design in terms of hardware, software features, GUI and technical interface with streaming systems and of course, target retail price, which from what I have been told knowing something of the costs, would be around $6000 (US) for this all-in-one high end box.

    Over to you. All considered and justified features will be discussed in a meeeting next week. Those present will be reading this thread over the next four days.
    Alan A. Shaw
    Designer, owner
    Harbeth Audio UK

  • #2
    Built-in DAC is essential

    I would be looking for an amp that had a built in DAC capable of decoding all sample rates up to 24/192. Then there is no need to worry about matching input sensitivities. Ideally the DAC would have S/PDIF (coax and optical),HDMI, and USB inputs. Asynchronous USB would be desirable.

    I would consider a phono stage definitely as an optional extra.


    • #3
      DACs in streamer units - build in

      One of the things about streamers, particularly upmarket streamers is that they will all have sophisticated DACS within them. It would likely be the case that dedicated streamer users will want to take the analogue signal from their streamer unit to the amplifier's input, and then the issue of input sensitivity matching is introduced.

      If the amp has in-built DAC then one or other of the DAC's will be redundant. I cannot think of a good solution but then again I am not an audio engineer.

      I just know I would much prefer an amp with in-built DAC.


      • #4
        My Harbeth amplifier

        Vital: adjustable gain on all inputs, Tape Loop, Pre out, remote
        Optional plug in: Phono, DAC (min. 2x S/PDIF, 2x optical/TOS link, 1x USB)

        Retail price hopefully nearer to 3000 Euros (there is an English apmlifier with optional phono and dac boards, 110 Watts into 8 Ohms, just lacking the tape loop, for around 2500 Euros)

        {Moderator's comment: What is that amplifier please?}

        To Moderator: Creek Evolution 100A. Alan Shaw used it in Bristol IIRC.


        • #5
          Quality components

          The vast majority of my customers use turntables, so a phono stage would be very desirable. This could be an add-on, plug in board so that those without a TT aren't paying for something they don't need.

          Similarly with a digital input and internal DAC. Many already own a DAC or quality CD player, so an add-on board would suit everybody. Another thing is that digital does tend to change, as manufacturers chase the numbers game. An optional plug in board could be upgraded as new procedures become available.

          Adequate output, reliability and a remote are important. No one ever asks about tone controls or room correction. Put the money into quality components.


          • #6
            Apple AirPlay?

            Does anyone know anything about Apple 'AirPlay' and its relevance to high end audio? Is is a super-set of Bluetooth? Is it popular? Up and coming? Useful?.......
            Alan A. Shaw
            Designer, owner
            Harbeth Audio UK


            • #7
              Wish list

              Vital: sufficient power naturally, variable gain at input (usable from front), tone controls.

              Desirable: clip indicator

              Optional: Phono stage with subsonic filter (switchable). DAC inputs.
              Getting to know my C7ES3


              • #8
                Potential features and market

                Vital: sufficient power for all models from P3ESR to M40.1, good power saving standby mode, remote control, variable gain, realistic input sensitivities

                Desirable: tone controls, clip indicator, main in / pre out inputs

                Optional: phono stage, DAC inputs (S/PDIF, optical, asynchronous USB) - all on add-on boards ready for easy future upgrades

                Useless: tape loop, headphone amp (at least for the manufacturer of loudspeakers)

                To think about: whether the Harbeth amplifier should be an integrated and/or separate amp? The latter design choice gives more flexibility with regard to both power demands that much vary between different Harbeth models and the digital features that can be implemented in the preamplifier only to save the power amplifier from getting outdated.


                As regards the digital side of the design, I would think that 90% of those amplifiers, at least during the first years of manufacture, will be bought by existing Harbeth customers who, as it seems to me, are rather conservative. Therefore, in my opinion you should focus on quality components, reliability of the product and providing future maintenance at reasonable cost.

                I'd rather see a simple remote, instead of control via wi-fi, iPad and/or in-built LCD display, DAC inputs only on an optional plug in board for those who really need them and leave the features like Air-play, DLNA, Bluetooth or Wi-Fi to the manufacturers of streamers because it is not very likely that you would be able to implement those features so well as they do without the (expensive) help of talented programmers. Moreover, those digital standards change all the time while the Harbeth amplifier should be built to last.

                At the moment, for example, Tidal hi-fi streaming option seems very interesting. But will it last? WiMP was popular too and supported by many equipment manufacturers, but as for today it doesn't exist anymore. It's hard to keep up with those rapid changes in digital market. But for now it seems that direct streaming of the digital content, without the need to download it to the user's hard drive, will prevail. It is definitely much more convenient for everyone, including customers, record companies and equipment manufacturers as the whole system ready for downloading and/or ripping of the content, storing it and sending to the hi-fi system is very complicated and puts off many people from the so-called PC-Audio.

                Streaming is much more convenient than dowloading, but it's hard to say whether Spotify, Deezer, Tidal or any other service, and there's plenty already, will dominate the market in the end. Probably it would be sensible to stick by the big players like Google (Google Play Music) or Apple (Beats Music) but Tidal is currently the only service that provides streaming of the content in CD quality. All the others currently provide streaming/digital radio at 320kbps at best.

                Summing it up, I'd rather see a conventional amplifier with manufacturing cost reduced and retail price closer to 3000 Euros. Retail prices of the competing amplifiers have to be taken into account as well. If the retail price of the Harbeth amplifier is sensible, I am sure that huge number of the existing owners of Harbeth loudspeakers will be looking to buy.


                • #9
                  Digital features

                  My 2 cents...

                  Vital: Inputs - RCA, optical and co-ax digital, USB (async); input gain control; tone controls (bypassable & stored on a per input basis); standard IR remote control

                  Desirable: Ethernet connection for TCP/IP streaming (SMB/NFS client); Extensible software for new digital formats and streaming standards - able to be updated over the internet (e.g. AirPlay, ChromeCast, DLNA, Sonos, etc, etc...); mobile app remote control.

                  Optional: Phono module; WiFi module; bluetooth module

                  The reason I included the digital domain stuff is that they are relatively cheap as far as components go and make the amp much more attractive (at least for me!)


                  • #10
                    My spec sheet and market overview

                    I think at the budget end a receiver like the Yamaha R-N500 ticks just about all boxes: 2x80 watt rms, airplay, dlna network connectivity, coaxial and optical digital inputs, wired internet connectivity, remote by apps for android and apple. Tone controls and input sensitivity selectable through the app. It even has a phono in, and a pre out.

                    My suggestion would be to buy one and experiment at home until you appreciate the possibilities for yourself. I do not think Harbeth should ever dream to compete with such offerings: just is cheap and excellent gear for the smaller Harbeths, used in smallish rooms. Comparable specs can be found in micro systems like the Denon Ceol Piccolo.

                    What is Airplay: a licensed Apple protocol. It differs from Bluetooth in two ways. First, it is fully CD Red Book quality. Second, unlike Bluetooth it is not a device to device protocol, but something using the domestic wifi network. Apple laptops, ipads and iphones have it. There is third party software to give the same functionality to windows and android devices. You can use it to stream music wirelessly in redbook quality from your phone/tablet/computer to your audio system.

                    A Harbeth amplifier/system can only succeed at the expensive and powerful end of the market. So the power amplifier (separate or integrated) should have plenty of power to drive M40's in larger rooms, but also other and more difficult to drive speakers. The only other desideratum for me would be electrical efficiency. I am in the process of getting solar panels installed, and I do believe we owe it to the next generation and to the planet not to waste electricity. Maybe look at the Benchmark AHB2 for inspiration.

                    I do not believe in dedicated streamers. I think these closed systems will go the way of the dodo, just like dedicated word processors did once pc's came to the market. So for me a small headless pc is the ideal source, controlled through windows remote from a tablet. You may not want to get into this market, but it may be attactive to offer a matching fanless case for micro pc boards, with just a slot for one bluray drive. Any pc shop can build a basic pc into such a case that will do all that is needed, and rebuild it with a new motherboard a few years later.

                    This then leaves the pre amplifier, either separate or integrated with the power amplifier. For me, analogue inputs are a waste of resources, but the market may demand otherwise. So my suggestion would be to have two slots for plug in boards. You can then offer three types of boards: line level analogue, mm analogue, and mc analogue. These should all be adjustable/programmable for optimum matching. Make sure that these slots can all be used for later digital input boards as well, to cope with new technologies.

                    The essence would be digital inputs, however. Here I would like at least one usb input, two coax inputs, and two optical inputs. I don't particularly believe in support for HD audio formats, but the market will demand them. As for connectivity, I think you need dlna standard connectivity for home network connection to a NAS (networked hard drive for ripped music and films, approachable from any computer or player in the home network - like a Denon Ceol Piccolo in the bedroom) and Airplay. Wired ethernet is mandatory, wifi desirable in the market (perhaps on a separate board to enable later upgrades - this is a rapidly moving technology).

                    Traditional remotes are on the way out: you need apps for Apple and Android to control the pre amplifier. Digital tone/balance controls can be built in. However, I would prefer the full feature set of something like the DSpeaker Antimode Dual Core. That has dsp room equalization, but also tone and tilt control, plus manual eq filters for the entire spectrum. If tone controls are a good idea, implementing them in the digital domain gives far more precise possibilities.

                    Whereas power amplifier technology is not changing that much (even though manufacturing technology does change), standards and possibilities in the digital domain are moving fast. So the dac/preamplifier should be ugradable as much as possible, but there is a practical limit with as yet undiscovered new technologies. As a consumer I therefore expect to have to replace the dac/preamplifier well before the power amplifier. For expensive gear I therefore would prefer to have a separate power amplifier that I can keep well after the pre amplifier/dac has had to be replaced. Separates also allow for two power amps with say 250 watts and 500 watts per channel, depending on requirements, or two in bridged mode.

                    Finally, and this is a very personal thing, I like my gear small, and minimalistic looking. For styling, Dieter Rams would be my inspiration, rather than the dull and horrid retro styling of e.g. Leben. If I look at the section 'pictures of my Harbeths' I am struck by the prominence of modern decor.

                    If you want to sell in countries like the Netherlands or Germany, I think you need a modernistic design. I would never pay big money for something looking like a 1950's radio or worse.


                    • #11
                      Good Yamaha

                      Originally posted by willem View Post
                      I think at the budget end a receiver like the Yamaha R-N500 ticks just about all boxes: 2x80 watt rms, airplay, dlna network connectivity, coaxial and optical digital inputs, wired internet connectivity, remote by apps for android and apple. Tone controls and input sensitivity selectable through the app. It even has a phono in, and a pre out.

                      My suggestion would be to buy one and experiment at home until you appreciate the possibilities for yourself. I do not think Harbeth should ever dream to compete with such offerings: just is cheap and excellent gear for the smaller Harbeths, used in smallish rooms. Comparable specs can be found in micro systems like the Denon Ceol Piccolo....
                      In regards to Yamaha R-N500 being a good product I agree, same with the Pioneer N50/70's, good products. I used to use an expensive Linn streamer as a source, but that was sold off a long time ago.

                      Regarding amplification, I still cannot fathom the vast differences in price per Watt.


                      • #12

                        optional add-on:
                        Phono stages MM / MC
                        DAC (current version, I don't what are the latest version)
                        Balanced input

                        Tape in / out
                        Pre out / power amp in
                        tube output or input buffer
                        headphone output
                        loudness compensation
                        AV bypass

                        must have:
                        oN/OFF button on front faceplate
                        Class A / AB type of amplifier (like Simaudio, they have first 5W operating in Class A)
                        one set of L/R speaker output only
                        remote controller with mute, On/off
                        power output + robust power reserve (large high efficiency transformer)
                        low power consumpion standby mode
                        wide Freq response / Bandwith
                        Tone control
                        Digital volume display and input
                        MOS-FET output stage
                        nice faceplate, simple and clean look button


                        • #13
                          What's the catch?

                          That Yamaha R-N500 looks astonishing value, here.

                          I'm not up on all this streaming stuff* - what doesn't it do for GBP 300 incl. tax?

                          *I'm rather ambivolent about combining computer and audio technolgy. In my old fashioned way of thinking, if music is worth playing, it's worth owning. And that means a physical media that I can collect, is at arms length and is mine forever. Yes, I know: old fuddy duddy thinking and I'm well aware that my personal requirements are not those of today's market.
                          Alan A. Shaw
                          Designer, owner
                          Harbeth Audio UK


                          • #14
                            Is DLNA that useful in an amplifier?

                            This is a response to those who have put forward the suggestion of network DLNA compatibility. I have never found it that useful as a bundled feature and I would consider that it would be particularly over the top in an amplifier. I am ready to be proved wrong but here is why I think it would be opening up a can of worms.

                            The amp would presumably be a DLNA client. My understanding about DLNA clients is that they "pull" data (media files) from DLNA compatible media servers. There would need to be a monitor/TV screen attached (or at least an app in a remote smartphone/tablet computer) to link up with DLNA servers and navigate through the various media libraries, not a good point for an amp (but excusable for a Home Theatre amp). The DLNA client in my blu-ray player is very basic and cannot play music files back gaplessly.

                            The Simple Audio Roomplayer (a streamer unit by ex-Linn employees) complete with amplifier never got gapless playback working before they went bust I believe. It would be a big ask to expect a Harbeth amp to jump this hurdle when the Simple Audio team whose efforts were surely focussed on the streamer side of things rather than the amp never got gapless playback as a working feature of their streamer/amp.

                            This discussion is about amplifiers not all-in-one streamer/amplifiers. I would certainly want a streamer/amplifier to do all that I expected from it (gapless playback included). I would not want an amp with some media playback capability built-in, if it only did half a job (i.e. no gapless playback)

                            I would be in favour of airplay and/or bluetooth capability where data as media files can be "pushed" to the amplifier from an independent playback device such as a 'phone, tablet computer, or desktop computer.

                            Please feel free to disagree if my perception of DLNA is wrong.


                            • #15
                              The real value of features

                              Regarding the proposed $6000 market price...

                              I don't see how this delivers value for money over my Yamaha A-S501. That paired with a streaming box of some kind will do exactly what I want for 15% of a $6000 asking price. What would the other 85% bring me?

                              If we accept the 'all reasonable quality amplifiers sound the same' argument, which I tend to; then all we are comparing is features.