Archived from Audio Direction Ltd.
1. One of the most important of things to consider is to bring along a CD you are familiar with. Audition components only on music YOU are familiar with. Every store and salesman will have favorite discs from which they can cue up selections they know will sound good….bring something YOU know.
2. Audition music at the levels you will listen to at home. A favorite trick of audio salesmen is play music at extremely loud levels. Usually louder sounds better, but it may not reflect the levels you will use at home. All speakers have a “break” point, a point at which the various components ( tweeter and woofer, for example) comes together. For some speakers that can be quite loud, far louder than you may be comfortable with at home in your environment.##
3. Check the frequency response: how high and how low does the system perform at. Remember tonal balance is just that: a balance. Too much highs and the system will become irritating over time. Too much bass and the system tends to sound murky and boomy. The balance point is the midrange: human voice, both female and male. Use a recording with both for audition. In a smaller speaker, expect a little roll off on the highs to compensate for the lack of deep bass.
4. Human ear sensitivity are centered on the frequencies of human voice. Even though the nominal range of human aural response is 20 Hz to 20kHz, the critical band width is the human voice, about 80 to 1200 cycles. The human ear is most sensitive to these frequencies (just think about the speaker in your phone: gotta be one of the cheapest ever made and yet with a simple hello, you can tell who is calling you).
Now octave wise, human hearing roughly spans ten octaves, but octaves are not linear, but logarithmic in nature to compensate for the human ear itself. Twenty cycles to 40 cycles forms the first octave, a mere 20 cycles, but 10,000hz to 20, 000 hz forms another octave, some 10,000 cycles.
Human voice covers about four octaves of the ten we normally can hear. As we age, the range of hearing diminishes, usually in the top end first. With males, normally the hearing drops in the right ear first as most people are right handed, and that is the hand normally used to hold power tools and appliances.
Hearing loss is quite common but curiously the brain compensates for the loss. With constant exposure to live music and such, the brain learns to compensate for the loss of hearing ( say, as in a reaction to certain antibiotics).
So 30 cycles can mean almost half an octave on the lower end, whereas 5000 covers a similar half octave on the top end. This displays how non linear the human ear is.
5. Dynamics is another factor important to consider. Many stereo components can play loud emphasizing the initial transient attacks on notes. Many have problems in controlling the follow through of the note. There has to be a balance between the initial attack and the tonal texture which follows. In the audio field we make the distinction between micro dynamics and macro dynamics: the difference between the softer passages and the louder ones. This is important when listening to music at less than full rock concert levels. There needs to be a certain kind of evenness in the sound consistent with the loud and soft passages.
6. Coherency. This one is often overlooked by many, many designers. One of the best ways to assess this is to listen to piano music. A piano is ONE instrument and should sound the same as you go from the lowest notes to the highest. I have heard speakers where a run on the piano sounds like different instruments as you ascend or descend a scale. For my listening it is unacceptable and reveals issues with both timing and phasing of the drivers.
7. Reliability. Do a little internet research, certain manufacturers have a very checkered history in regards to components failing. Sometimes the failure may be just a few components. The old Counterpoint SA 20/220 were notorious for failure, often pyrotechnic. Ditto the Audio Research Reference 600’s. On the other hand, a manufacturer like Quicksilver will often downplay a bit of performance in favor of superior reliability. Considering that Hawaii is 3000 miles away from any continent, sending back components will cost you an arm and a leg. It makes only UPS and FedEx happy.
8. One associated facet linked to reliability, at least for electronics, is heat. The hotter an component runs, the more apt its service life will be shortened. This is because capacitors, which are used everywhere, have definite temperature ratings. Normal rating are 65/85/105 degree Celsius. A 105 C is the boiling point of water, 85 C is about 185 F. If the chassis of the component run so hit you have difficulty placing and keeping your hand on it, the heat will “kill” the capacitor, eventually shorting it and when that happens it will take down other devices with it.
Pure class A amps used to have the reputation of superb performance, but their heat eventually always destroyed the amplifiers. There are many other innovations which have lowered the heat output and improvement in transistor technology have also added to the performance envelope without the need for heat.
9. Beware of “eye candy”. Many components these days, particularly those from the Orient, have beautiful aesthetic designs. However, it doesn’t mean that the inside construction will match the exterior. The final proof is always in the listening, and in the longevity of the component. Some designs like the late Golden Tube, were extremely affordable and gave more than acceptable sound. In our experience, though, every amp we sold failed, and unfortunately. kept failing. Using one defective component is not uncommon and we come across such quirks, well, more often that we care to admit. Once we know, however it is easy to replace that part before delivery to the customer. In case of Golden Tube, the failures were of multiple origins and we could never get a true fix on the cause of the failures.