Taralabs cables

Even the biggest, costliest amplifiers exhibit this power loss at the frequency extremes, but in these, the losses don't usually start until well beyond the audible range.
Let's assume now that we have access to an amplifier's power response curve, and can see that it will deliver its full rated power to 20Hz. Is this any guarantee that it will sound the same, at low levels, as a high-powered unit? It is not.
Power response curves show the power levels at which different frequencies will generate the same 2% distortion at which the midband power is usually rated (fig.3). What they fail to show is distortion at less-than- maximum power levels. An amplifier that yields 2% distortion at full rated output may yield 0.2% at half power, or its distortion may never drop below 1% regardless of how little power we drive from it. And since we do most of our listening at power levels far below overload, the amplifier's minimum distortion, or "residual" distortion, is of considerable interest to us. Here, again, is where the typical low-powered job falls far short of its heftier ilk.

The light output transformer in most low-powered amplifiers is susceptible to core saturation at low frequencies, and even though this may be held low enough to meet overload limits down to, say, 20Hz, it nonetheless imposes a severe limit on the amplifier's low-frequency residual. Thus, typically, the low end will exhibit increasing distortion with decreasing frequency, even at the very lowest output power levels. At 1 watt, where the mid-band is contributing only 0.3% or so distortion, there may be 1% distortion at 30Hz.
Actually, it is a rare low-powered amplifier that will produce as little as 0.3% distortion at low levels, even through the midband. Most of them, sloppily designed as they are, have enough distortion in their earlier stages to hold their residual at about 0.75% no matter how good their output stage may be, so they can never sound as good as the more carefully designed high- powered units. The few exceptions to this rule are so costly that one might just as well buy a higher-powered unit and be done with it.
There are extenuating circumstances occasionally, though. Loudspeakers and amplifiers that ate designed specifically for one another should be used together regardless of the amplifier's power rating. Some speakers are fragile, and will burn out if hard-hit by a hefty amplifier. Fusing helps, but the series resistance in the line reduces the electrical damping applied to the speaker, inhibiting the amplifier's ability to prevent spurious cone vibrations. Consequently, if you must use such a speaker, it's advisable to bypass its fuse, and couple the speaker directly to an amplifier that won't be able to damage it.

High-power advocates have always claimed that one reason a high-powered amplifier sounds better than a top-notch low-powered job, even at low levels, is because the big one's reserve power gives it better control of the speaker's voice-coil. It was reasoned that a large reserve of power, operating through a tight negative-feedback system, could bring more power to bear more rapidly for suppressing spurious vibrations of the speaker cone. This sounded plausible, until the first of the all-transistor amplifiers came along and befogged the issue.
Transistors just do not behave like tubes. Transistor amplifiers whose measured distortion is higher than that of the cheapest "hi-fi" amplifiers somehow manage to sound much better than they should, and the absence of an output transformer from most transistor amplifiers (the low-impedance transistors connect directly to the speaker) eliminates most of the annoyance value of marginal overload on peak passages. As a result, a transistor amplifier seems to produce far more clean power than a tube amplifier of the same rated output.

Even more significant, however, is the "transistor sound" at low output levels. Even the feeblest transistor amplifiers we have heard (a 3-watter, for instance) sound like high-powered amplifiers when operating at low levels. They are transparent, crisp,and have the same kind of bass solidity that high- power advocates have always attributed to the monster amplifier's reserve of speaker-controlling watts. So the superiority of the high-powered tube amplifier is not just a matter of reserve power.
Just what it is a matter of is still open to question, but we may be in a better position to answer this when we get the opportunity of comparing high-powered transistor amplifiers with their betubed competitors. Tube amplifiers have fouled up the power question for years, because the low-powered ones so often suffered from shortcomings that had nothing to do with the simple fact that they were 10- or 12- or 15-watt amplifiers. Transistors may change the picture.

So, where do we stand? For the nonce, let us say that computed power may be taken as the power we should have on hand if we use a transistor amplifier or a high-powered tube amplifier. In the lower-power categories, tube amplifiers in general will not produce the best sound that the average speaker can furnish. They may be adequate, and can nonetheless provide enjoyable listening, but they do leave room for improvement. Whether or not the improvement is worth an additional outlay of money to you is up to you. But it's there for the buying