My system sounds rather bright and thin. A friend of mine suggested that I should get a tube preamp to solve this problem. What do you think?
H. Krause - Albuquerque, NM.
Lately I have been getting calls and letters pertaining to system fixes via the insertion of a “magical” piece of tube gear. This fix is a myth and worse than that it is a slap in the face to all the well-designed modern tube equipment. The popular press has certainly helped to perpetuate this myth and has contributed to the current renaissance of tube equipment. Whether using tubes or solid state devices, the aim of most designers is to produce a neutral and accurate portrayal of a recording. While it is true that early tube designs suffered from poor bass extension, rolled off high frequencies, and a propensity to be overly warm and thick sounding in the midrange, modern tube equipment need not suffer from these ills. With many years of refinement and much better output transformers and power supplies modern tube equipment is on the cutting edge of the state of the art. Modern tube equipment that sounds like old tube equipment exists either because it is poorly designed or designed to serve as tone controls for poorly balanced systems. The same holds true for solid state equipment. The early solid state equipment was really bad sounding: thin, bright, tizzy, mechanical, and fraught with all sorts of pain-inducing distortions. No would recommend that we search out these old designs to balance out any system.
There are several other myths regarding tube design that should also be dealt with. Reliability. This is probably of paramount importance to most buyers and an area that most people feel tubes fail in. Not true. The best designers use the proper tube for the application. In other words not all tubes are best designed for all purposes. What works well for a guitar amp may not be good for a phono preamp. These tubes are used in circuit designs that operate the tube within its intended electrical load and performance parameters. Hot-rodding tubes (pushing the envelope of their performance, either in the noise floor department or the electrical department) will surely result in decreased life expectancy and uneven performance. The types of tubes that are used should be generally available and not require a trek to some far off land in search of the last matching pair. I realize that many people are not aware that any tubes are readily available but you should realize that high end audio is not the only nor the largest user of tubes. Radio stations, the military, ham radio operators as well as many professional musicians all use current (designed in the last 10 years) tube equipment. They do so for many reasons ranging from sonic preferences to performance concerns. Many of these same tubes are used in audio and a plentiful supply should exist for quite some time. Good tubes, competent design, and execution will translate into a long service life for the equipment. With all of these considerations addressed you should expect anywhere from 3 to 10 years, depending on the design, from a set of tubes. Serviceability. Most tube equipment is hand built using point-to-point wiring (the way all equipment used to be built) which makes it very easy to repair. Parts are accessible and circuits can readily be followed. Noise. Tube equipment does not generate any more noise than the best of the solid state electronics. Whether it is residual noise from the electronics or various hums and buzzes I have found no consistency to either solid state or tube equipment to be firmly planted in one camp.
This is not to say that all tube equipment will reach these standards just as not all solid state equipment is reliable, serviceable, or quiet. However it does mean that you should not accept tube equipment that does not meet these standards. There is a plethora of tube equipment on the market at this point, much of it made and sold by people who are cashing in on the current resurgence. The longevity, serviceability, and sonic results of much of this equipment leaves a lot to be desired. As usual once you get past the hype and deal with the less glamorous and mundane reality you will find there is a much different story to be told. Use common sense and your ears and simply listen.
In answer to the question, it is very important to have all the parts of a system individually come as close to natural sound as possible. Think of a system as a balance beam. Each piece of equipment will likely fall to one side or the other of the balance point with the end result hopefully balancing out the beam. However while +10 and -10 would balance in math the same thing can not be said for audio systems. The further each piece of equipment is from the neutral ideal the less chance you will have of ending up with a balanced result. An overly bright system will not be fixed by introducing an overly warm component. A system that is way out of balance will unfortunately require a rethink and possibly several replacements.
© Cadence Magazine 1995