Amplifiers magnify the small voltage signals of source components into the larger voltage swings and current that loudspeakers need to generate sound at room-filling volume levels. Preamplifiers primarily provide the means to select input sources and control volume. Phono stages are specialized amplifiers to boost the very low signal levels of cartridges to the same level as line stage components like CD players and DACs. An Integrated amplifier is a preamplifier and amplifier combined into one box sharing one power supply. Preamplifiers and Integrated amplifiers may or may not incorporate a phono stage, headphone output, or DAC. To be called an "all-in-one" unit today, streaming functionality should also be included.
The matching of amplifiers with speakers affects sound quality since both have their own sound. Generally a larger room will need larger speakers and a more powerful amplifier. Deeper bass will also require larger speakers and a more powerful amplifier. Amplifiers also vary in their ability to deliver short bursts of power versus sustained power and the relative magnitude between the two. Which is more important, higher sustained power, or greater ability to deliver short bursts of very high power?
Amplifiers are inherently non-linear devices full of non-linear circuit components and the realtionship of output versus input is not a straight line. The output is not a perfect magnification of the input - and distortions of various types occur that are worse as power output increases. Distortions are also time dependent and some amplifiers are more nimble able to react faster to a rapidly changing input signal than others. Amplifiers have different overload margins, ability to drive current into different loads at different frequencies, mains power supply noise tolerance, and warm up times. Potential purchasers like to compare "specifications" but these vary according to how the test is done and may only represent how an amplifier behaves in a very contrived particular situation that is not real world. Sound quality is strongly related to how well an amplifier is made. More expensive amplifiers take longer to build and use selected and/or custom manufactured components, more sophisticated manufacturing methods, and more hands on adjustment and verification steps. Cheap amplifiers are built quickly with wider tolerances using off the shelf components and less rigorous calibration adjustments.
At kemela the emphasis is on solid state.
While tube designs have the virtue of simplicity, they are more expensive to build, suffer from performance deterioration over time, have higher cost of ownership from the need for tube replacement maintenance,
and put out more heat which is a consideration in the south.
Analog to digital processing of recordings is far better now than before, and the blur smoothing and noise dither to soften "hard" recordings of all but the very best - and expensive - tube designs is no longer required.
Today's DACs have far greater bass, textural, temporal, and spatial resolution that will expose loose bass and smear in subsequent amplification.
kemela does have well-engineered moderately priced tube monoblock amplifiers, however, for those looking for tube sonic tendencies and dynamics with few of the shortcomings. They still have their place for those that like the sound and the looks. Inexpensive or kitchen table built ones are unlikely to remain in your system for long.
Deciding how much to spend on a system and the allocation of funds accross the parts of a system is never straight forward. Matching amplifiers and speakers (and speaker cables!) is important to get right to get the most out of each part. kemela carries electronics with various personalities and strengths. Most of the manufacturers we carry we offer a portfolio of products that go well together but we are experienced in partnering appropriate speakers and specialized source components for those who would rather not get too overwhelmed by the on-line research process. You should carefully consider your requirements and then we can steer towards an appropriate platform. Some are more orientated towards analog, others digital. You have to like your amplifier as much as your speakers.
The length of time you plan to keep an amplifier may determine if the manufacturers warranty is important to you. Who, where and how long it takes to have a product serviced is also relevant. Do you care about upgrading?
kemela maintains close contact with manufacturers by visiting the factory where possible and having regular communication.