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Gold Member Username: Jan_b_vigneDallas, TX Post Number: 8938 Registered: May-04 | . http://www.harbeth.co.uk/faq/index.php#13 1. Tell me how I should evaluate a loudspeaker. What should I listen for? What would make a good test track? I don't have any technical equipment or knowledge. (Revised Jan 2006) Download MP3 text-to-speech answer of this question. (Under revision) (Open MP3 player in a separate window if you wish to read and listen). First of all, let's define what Harbeth offers and check it's what you're looking for. Harbeth loudspeakers are precision instruments and are used at home and in professional studios. They contribute very little of their own character hence they are of 'low colouration' design. Harbeths have outstanding clarity and naturalness in the critical middle frequencies and a wide dynamic range and are suitable for all types of music at a sensible replay level. In evolutionary terms, music is a very new invention dating back only 35,000 years or so and is not, in practice, as analytical a 'test source' as one might hope for. Our auditory system has been honed by evolution for the interpretation of human vocal sounds, not music. Most loudspeakers are coloured to greater or lesser extent, and the use of recorded speech is devastatingly revealing of loudspeaker artifacts in a way that music, unfortunately, is not. With some practice you can become really skilled at interpreting recorded voice on conventional loudspeakers so that buzz words like "nasal", "beaky", "quacky" and "honky" become self-evident. Note that these adjectives, often used to describe loudspeaker artifacts, are those associated with the mouth, nose and chest - not of musical instrument. Alexander Graham Bell discovered at the start of the electric sound age that the 'telephone band' of only about 300Hz to 3kHz was of paramount importance to our ears. Later, when A.M. (medium wave) radio was invented, this bandwidth was opened a little for better reproduction of music - but only by a little. So, by definition, the majority of musical energy falls in an audio band equivalent to that of disconnecting the tweeters on your loudspeakers. It also means that the defining quality of a loudspeaker system is not at the extremities of the 20Hz to 20kHz audio band but in the lower-middle through to the 'presence' region: only about one quarter of that full audio band. You can form at much of your final opinion of a loudspeaker's capabilities before you have played the first note of music if you use male and female speech and vocals as a test source. You don't ave to know the real voice in person but it's ideal, of course, if you can make your own test tape of a familiar voice, recorded outside on a windless day with a really good microphone - a subject in itself. Replaying speech backwards, or spoken in an unfamiliar foreign language also breaks the emotional associations between the sounds of the words and their meaning and aids analysis. Whilst there are many examples of technically excellent recordings there are few recordings which can be trusted as having captured the bloom and warmth of the performance without processing, equalisation and the use of large numbers of spot microphones to showcase individual instruments. A concert really isn't like that at all: live sound is warm, lush and clean, has a huge dynamic range in reserve and the instruments intermingle together into a floating curtain of sound that is quite unlike most people's impression of home hi-fi. If you play an acoustic instrument, remember that when you play your own instrument that you are listening in its nearfield. This is a much 'harder' sound than a listener in the audience would experience and it would be tempting for you to select a speaker that mimics that more intense sound. But be sure to switch back to a speech recording again - and you'll reset your internal frame of reference. Piano can be revealing not only of the big details but the micro detail in the decay as the notes fade into the silence in a large hall. But as with so many instruments, much depends upon the recording. A piano in a small room (or even one in the concert hall with a microphone under the lid, close to the strings) will sound so different to a concert piano, in a big hall with the lid open. Blues, jazz, folk, or 'easy listening' music with simple instruments and vocal is also interesting and revealing of stereo positioning and depth in a different way to large scale performance with lots happening at once. Do not use solo pipe organ music to critically evaluate loudspeakers because no matter what problems the speaker may have, the harmonic structure of pipe organ seems to be sympathetic to loudspeaker defects and will tell you nothing about the underlying problems (if any) of the speaker in the middle and upper frequencies. Conversely, brass instruments are really revealing of cone colouration due to their rich harmonic structure, and showcase Harbeth's RADIAL cone technology. Conventional cones soften the transients of brass instruments as you will hear for yourself. A good salesman will play you recordings that highlight and compliment (or disguise?) the characteristics of a particular speaker or recording. Do not be embarrassed about bringing a stack of CDs or disks with you to the hi-fi shop and be sure to make an appointment in advance. You will need lots of time and a good dealer will expect this and make a date for you. Above all guard against being impressed because natural sound, as you would hear it in the hall, is not 'impressive' in hi-fi terms except in its lightness of touch and freshness. Good loudspeakers should create a curtain of sound and not push the performers onto your lap. Really good speakers are impressive in the way they reproduce the small details, the micro tones in music and not by how loud or attention grabbing they are. One of the remarkable characteristics of Harbeth's RADIAL cone technology is that no matter what they are tasked with reproducing, they just don't fog over the details as conventional cones do - listen out for that. You can find more about the recording process and a detailed analysis of the typical subjective characteristics of hi-fi and studio monitor loudspeakers in our Designer's Notebook Chapter 7: The curtain of sound. Why not keep a printed copy to hand when you evaluate loudspeakers? . |
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Bronze Member Username: JawPost Number: 30 Registered: Mar-06 | Just put on a pot of coffee. When I finish (trying to) comprehend it all, will make a wild stab at a comment with no concern at all over sounding like Elmer Fudd. |
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Gold Member Username: Edster922Abubala, Ababala The Occupation Post Number: 4369 Registered: Mar-05 | Nice link, Jan! That seems to be an unusually information-rich website. A concert really isn't like that at all: live sound is warm, lush and clean, has a huge dynamic range in reserve and the instruments intermingle together into a floating curtain of sound that is quite unlike most people's impression of home hi-fi. If I read it correctly, the writer is an admirer of live music but does see a number of difficulties in using it as a reference: "A concert really isn't like that at all: live sound is warm, lush and clean, has a huge dynamic range in reserve and the instruments intermingle together into a floating curtain of sound that is quite unlike most people's impression of home hi-fi. If you play an acoustic instrument, remember that when you play your own instrument that you are listening in its nearfield. This is a much 'harder' sound than a listener in the audience would experience and it would be tempting for you to select a speaker that mimics that more intense sound. But be sure to switch back to a speech recording again - and you'll reset your internal frame of reference. Piano can be revealing not only of the big details but the micro detail in the decay as the notes fade into the silence in a large hall. But as with so many instruments, much depends upon the recording. A piano in a small room (or even one in the concert hall with a microphone under the lid, close to the strings) will sound so different to a concert piano, in a big hall with the lid open. Blues, jazz, folk, or 'easy listening' music with simple instruments and vocal is also interesting and revealing of stereo positioning and depth in a different way to large scale performance with lots happening at once." |
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Gold Member Username: Jan_b_vigneDallas, TX Post Number: 8939 Registered: May-04 | . Yes, I think anyone who listens to live music with a dynamic range of more than a few db's will quickly realize the tremendous difficulties involved in translating the live event to a reproduction system. Sit in close to a piano and you sometimes can't imagine how a system can do as well as it does. Sit mid-hall from a trumpet and you begin to realize the power of a single insrument. Not that long ago, I had seats in the top balcony of the Meyerson Concert hall and was astounded that a single violin could still have power and sweetness when heard from that distance. . |
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Gold Member Username: John_aLondonU.K. Post Number: 4453 Registered: Dec-03 | Excellent advice, Jan. Thanks for posting that. I was a step ahead, and was thinking that the test speech should be in a language that we DO understand. I also wonder how anyone can date the invention of music... Apart from which. Psychoacoustics establishes that distinguishing different instruments by their sound relies on a lot of short-lived high-frequency information in the initial transient; when the string, for example, is plucked/bowed/hit. Convincing and easily-intelligible speech also requires us to hear high frequencies in order to distinguish consonants. Nevertheless I think that quote contains good advice and makes a whole lot more sense than most things written or said in promotional material about loudspeakers. Yes, it is striking how clear and distinctive purely acoustic instruments can sound in really large rooms or halls. We have discussed bass and room size several times. When you hear real double-basses, bass guitars, large brass, or large organ pipes in rooms with dimensions of hundreds of feet, is becomes obvious that you just can't expect that sound in a living room, no matter how much bass extension you have in the system. You appreciate at once how the instrument itself is interacting with the whole volume of air around it. |
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Silver Member Username: My_rantzAustralia Post Number: 705 Registered: Nov-05 | I don't think most of us believe our systems (speakers) can truly emulate all live sound, but that we can strive for what comes closest within our budgets. The Harbeth site does contain some good information, though there will still be dispute about some of it I would think. Harbeth says potatos, others say potatoes. Some say spuds! |
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Gold Member Username: John_aLondonU.K. Post Number: 4455 Registered: Dec-03 | Or pommes de terre, if you will pardon my Spanish.... I've read some more of "Harbeth's Frequently Asked Questions". It is very good, for example "Do I need a subwoofer?" I like the last item, on MP3 and DAB, and there are good further links. Harbeth does not comment on SACD and DVD-A. Harbeth - Designers' Notebook - Stereo Imaging, Chapter 7 : Loudspeaker design: achieving a smooth image transition between left and right loudspeakers From page 4 there are some demonstration MP3 files; they illustrate clearly even on my computer speakers. If a loudspeaker evaluation through a blind curtain does not include a known reference loudspeaker (or better still, real live musicians or vocalists) then it is almost certain that under those quasi-scientific test conditions and with no visual cues and a short exposure period, the casual listener would usually select type C with a 'projected' balance or even type D. Types A (and B) with a more accurate but softer, less incisive sound would make less of an impact through the curtain. However, if a known reference is introduced, the situation completely reverses, and C and D would be exposed as coloured. Excellent. Listen after reading page 2. Great graphics. "Been there; heard that". We never sorted out "Stereo imaging" or "Soundstage" on the thread "Definitions", as I recall. |