Using effects for guitars in audio technologies has become a cornerstone of all music production in both live and recorded sound. Tube amps have been a staple of the recording industry almost since its inception, but much of the information on these amps have been lost in time and obscurity. There are very few, if any, modern tube amps; most of the tube amps in use today were built decades ago. A general rule of thumb is that the volume control is not a wattage or voltage control - meaning if the volume is set to half, it does not use half the full power.
The full power of the tube amp is always active regardless of the setting. To achieve a clean sound the "master volume" control should be turned all the way up and the regular volume, preamp, should be turned down to alleviate distortion. On the other hand, if distortion is desired then the master should be turned down and the preamp turned up to the desired distortion level. These are called tonal controls or tube amp tone control and it does depend upon the output of the guitar being used. Different manufacturers have different output levels for their guitars and no standardized output has been set. Larger areas for using the tube amp present little or no problem as most tube amps have great wattage specifications. It is in smaller settings that the volume control must be meticulously monitored and tweaked so the amp does not over power the rest of the ensemble. Use of the master volume is considered to be the best solution for this.
Tube amps present their own issues for troubleshooting as they work with different technology than solid state amplifiers and equipment. The most common cause of most problems is due to a cracked tube. The tubes supply the amplification power and "processing" of the analog sound; without it in functioning form, the tube amp could present a myriad of issues and likely problems. One of which is that even if the tube amp is on it does not produce sound, not even the hum of the electrical signal powering the amp. If fuses commonly blow or are rendered useless the problem may in fact be one of be several issues. Some the causes may be the power or rectifier tube being shorted or the power transformer may be faulty. Many issues can be averted using proper care and maintenance of the tube amp.
Tube amps provide better sound quality than solid state amps depending upon their use and application. In large settings it is advisable to use a tube amp as they will produce a better, more rounded, sound over larger areas with the same amount of power. They have a more well rounded frequency response delivering mid to low end sounds and frequencies better than solid state amps. The tube amp used in studio recordings can give added fullness to bass guitars and rhythm guitars as well as drum kits that are recorded through a tube amp. Engineers use tube amps to help in alleviating extra equalization on certain instruments and thus providing a better recording.