Components are critically intertwined; certain types of speakers perform best with specific types of amplifiers and the reverse is also true, albeit less so. This is a key concern for the audio system or component purchaser. Get the amp/speaker link wrong and no amount of tinkering will help.

Keeping in mind that music lovers focus mostly on the loudspeaker where they manifest a preference for particular replay characteristics, the obvious point of divergence in amplifier design is at that juncture where either vacuum tubes or transistors are selected as gain, or amplification devices. In recent years, some designers have mixed these devices, with very mixed results.

In the best situation, you would buy an amp and loudspeakers simultaneously; your chances of achieving great sound are much improved in this circumstance. As to power requirements, in all cases, consider the efficiency rating of the speaker. Designs rated at 91 dB/w/m or more can be considered high efficiency types, i.e., they need only a few watts, 10 or so, to go very loud in an average sized room. Designs rated at 86-91 dB/w/m may be considered medium efficiency models. The vast majority of speakers fall into this category. Look at amps rated at 50-100 watts per channel for models at the 91 dB/w/m end of the spectrum and at 70-200 watts per channel for 86 dB/w/m designs. As speaker efficiency drops, power requirements increase.

For some designs, you must have a big amplifier, and a good indicator of this is an efficiency rating of 85 dB/w/m, or lower, in tandem with an impedance rating of 4 ohms or lower. Consider amps of at least 150 watts per channel and if you like your music loud, narrow your search to the big 250 watters, which for most buyers means a solid state amplifier.

In a full-range loudspeaker, 90% of all designs will use a woofer of between 6Ó and 12Ó to deliver the low frequencies. At either extreme, small designs for second systems will get by with 4Ó or 5Ó woofers, and for the bass freak there are speakers with 15Ó woofers. Transistors amps excel in controlling the heavy motors needed to make a large woofer work as designed. The measurement to watch for in an ampÕs specifications is damping factor. The higher the damping factor the more control the amp exerts over the motion of the cone. One might think that a high damping factor is always preferable, but in fact, too much control can impart a dry quality to the lower and midband frequencies that may rob the music of harmonic content.

Many experienced listeners feel that a speaker driverÕs motion should decay at a slower rate from the onset of a musical event than is accorded by the extreme control of a big solid state amp. Such listeners are advocates for many of the key qualities of tube amplifiers, which include low damping factors.

If I were seeking to get the most out of a speaker that had a woofer of 10Ó or larger, I would look closely at transistor-based options, as I believe that todayÕs better solid state models do such a good job of conveying accurate response in the bass region. The loose (sometimes ÒflabbyÓ) bass dispensed by tube gear in such situations more than offsets the positive qualities displayed through the midrange and upper frequencies, where tube equipment is most likely to evince some superiority. This is not to say that I wouldnÕt recommend placing an all-tube preamp in a set with such a solid state amp, to exploit some of the good qualities tubes deliver.

Suppose your speaker has an 8Ó driver (or a pair or more of these) to handle the low frequencies. At this diameter, tube amps of 50 watts or more have a good chance of fulfilling all the electro-mechanical demands made by mid-sized woofer cones. Of course, transistor equipment is a perfectly viable alternative, and probably preferable if the overall speaker system is in the low efficiency category.

And for speakers with 6Ó woofers? At this diameter tubes work fine. Suppose you decide you must have a tube power amp, as you are convinced by the near-magical qualities of good tube designs. Thus, the amp choice may have taken priority over the choice of speaker. Audition speaker designs that employ an array of smaller drivers to deal with the low end. Maybe a design with four 6Ó drivers would do the trick for the tube electrically speaking, by vacuum tube designs.

And what about the top end? Make sure you gain some knowledge about how different tweeters sound. Personally, I prefer cloth or ceramic types, but I understand why some people prefer metal or composite domes, or horn loaded varieties. If you cannot tolerate ragged, screechy treble caused by bad source material or by cheap, poorly designed hardware, look at lower powered tube gear to supply you with consistently pleasant, musical results. To really put the problem behind you, consider triode tube designs only, which are generally the sweetest sounding way to go. Remember also that all things being equal, triode configurations deliver only half the power of pentode alternatives...But what a sound! (Continued next issue).