What is PMPO? Is it of any significance?
Peak Music Power Output is that amount of power in watts, which an amplifier can deliver for few milliseconds before it suffers permanent damage. Clipping which occurs in that process, also damages the speakers. No prudent person would ever play his audio system at its PMPO rating. But some manufacturers of audio systems want to project their products as better than what they really are. Hence this hype about the PMPO. Simply put, PMPO ratings are nothing but fraud.
Then what is the yard-stick of an audio system's power?
Root Mean Square Power Output is a better measure of an audio system's power. It is the amount of average power in watts which the amplifier can deliver on continuous basis (tested generally for 24 hours). High end audio equipment manufacturers go only by this value.
Is RMS power linked to fidelity?
Fidelity is a combination of the quality of the source (CD player / tuner etc.), amplifier, speakers, interconnects and speaker cables. Generally, well designed speakers with decent sensitivity (=/>86 dB), connected to an amplifier with adequate power, low distortion (<1%), good damping (>100), and flat frequency response (0.5 dB +/- from 20Hz-20KHz), show good fidelity, and can blow away those 4000 Watt PMPO all-in-one systems.
Which is the ''best'' speaker-amplifier assembly?
There is a subjective element in deciding which is the best. You have to listen alot, match the components for the particular sound you want, and choose according to your budget. Like the folks at Lithos say, ''hearing is believing!'' However, some broad guidelines on this topic can be found at ''Good Sound For Cheap FAQ'' available on the net.
Do the ''foreign'' equipment give better performance than the Indian ones?
The 'who is who' of high-end audio are from abroad, i.e., Arcam, Accuphase, Audionote, Azure Audio, Bryston, Classe, Cambridge Audio, Denon, Harmon-Kardon, Krell, NAD, Mark-Levinson, Marantz, Onkyo, Pilinus, Quad, Rega, Rotel, Snell, Teac, Yamaha, etc. for the amplifiers, and Axiom, B&W, Boston Acoustics, Mission, Paradigm, Polk, Magnepan, Monitor Audio, Mordaunt-Short, NHT, JBL, Jamo, KEF, Tannoy, Thiel, Wilson for speakers.
When it comes to speakers, mention must be made of critically acclaimed Indian brands like Pune based Cadence, and Lithos of Mumbai. There are other Indian brands, such as Sonodyne, Pro FX (collaboration between Denon & BPL), Acoustic Portrait, Lyrita Audio, Norge, Pulz, Sanen, Torvin etc., which too can be given a try. Comparing apples with apples, Indian brands are generally priced lower than the imported ones because of the availability of technical expertise and workmanship at low cost. Cadence ( http://www.cadenceaudio.com), Lithos ( http://www.lithosindia.com), Sanen ( http://www.sanenaudio.com), Sonodyne ( http://www.sonodyne.com), Torvin ( http://www.torvin.com), Pulz ( http://www.pulzaudio.com), Acoustic Portrait ( http://www.corrson.com), and Lyrita Audio ( http://www.lyrita-audio.com) have a web presence.
Do all good speakers share a similar design?
No. All good speakers are not made the same way, the reason being different manufacturers solve the bottle-necks in different ways. The choice in materials, design, and technology is tremendous.
What are the tips for arranging speakers in a home stereo-system?
A. The continuous output of the amplifier should be sufficent to drive the speakers. The impedence ratings of the amplifier and speakers should match. You should never carelessly connect low impedence speakers to an amplifier not capable of driving them, or else you would end up severely damaging your precious amplifier and speakers.
B. Pay attention to the polarity while connecting the speakers to the amplifier.
C. Decouple the speakers from the supporting platform by using spikes or rubber-feet at the bottom of the speaker. In general, the supporting platform should be rigid and non-vibrating.
D. See the manufacturer's instructions on spacing and toeing in the speakers. The crux of the stereo-sound is imaging, wherein you can exactly pin-point the location of an instrument playing on the imaginary soundstage before you. You can achieve this only by spacing and toeing in the speakers accurately.
E. Let speakers be at ear-level, not too high, not too low.
F. Use quality cables (the wires that connect the amplifier to the speakers) & interconnects (the wires that connect the source to the amplifier). Oxygen Free Copper cables (12 Guage or less) & shielded O.F.C. interconnects are a good choice, and most audio outlets in India sell them. Always use nickel / gold plated leads as they resist oxidation.
G. Do not place speakers very close to the corners of a room, but for a subwoofer.
H. Allow good ventilation for the amplifier.
I. Realize that the room in which the speakers are placed, and the manner in which they are placed, have profound effect on the quality of sound. Use a carpet in the room, if you can afford, to dampen the echoes.
Is high treble same as fidelity?
Indians in general have the habit of confusing high treble for fidelity. The mass-market speakers are given that extra "tinkle" to sound very bright. In reality, unnatural treble causes ear-fatigue, and makes you suffer from headaches and tin-ears in the long run.
What about subwoofers?
You can try a subwoofer if you want bass extension (=frequency extension by about 1-1/2 to 2 octaves on the bottom end), or bass reinforcement (augmentation of the existing bass frequencies). According to your purpose, the subwoofer needs to be connected differently to your amplifier. This is a subject in itself.
A quality subwoofer generally has high-excursion woofers of 8'' diameter or above. Without going into the types of subwoofers such as acoustic suspension (front-firing/ down-firing), vented (front-ported / rear-ported), band-pass (only the port is visible from outside), push-pull (where two woofers are sealed face to face and placed in a chamber), I can say that each type can sound excellent or rubbish depending upon the execution, which is again a function of the knowledge and means of the designer. Just remember that when you employ a subwoofer, the bass should sound real, and you should be able to hear both the hit/pluck of the bass instrument, and the ambient decay clearly. Bass is not the ''boom...boom..'' thing you hear from those multimedia ''subwoofers''.
Among the Indian subwoofers, Lithos-Terra-150 (push-pull design integrated into a band-pass) is excellent. The other note-worthy product is Sonodyne's Roar-R-III. Please be warned, that matching a subwoofer with your main-speakers, or placing a subwoofer in a small room, are real tricky issues, and bad matching or placement can actually worsen the sound quality significantly. Personally, I use a pair of Lithos Studio-1 speakers with the Lithos Terra-150 subwoofer, and I am extremely pleased with their sound.
All the best, and enjoy the music!
