Amps Questions Help

Hello Everone I am fairly new to hgh end audio and I have a question about amps. On Mark Levinson some of there amps say Dual Monarual?? What does that mean? and on Krell bias stereo?? what does that mean? I am looking for an amp that is truly balanced not just have the inputs that are xlr can someone help make sence of this for me. And maybe make some recomendation Thanks Mark
Hi Mark- Dual mono means that there are two totally separate monoaural circuits to make up the stereo pair. Two power supplies, gain circuits, etc. Some even have two power cords (not sure that ML does. This is designed to eliminate any interaction between the two channels. Balanced refers to circuit design (over my head), which requires XLR connectors. However, sometimes XLRs are supplied which do not feed a truly balanced circuit (they are there basically for convenience). Others can supply lots more detail, I'm sure.
Imagine a pair of mono-bloc amps built in ONE chassis, and with one power cord-- that's what a dual-mono amp is. A mono-bloc amp has only a single output-- to just one speaker, whereas a dual-mono amp has outputs for two speakers (left and right) and is thus also called a dual-mono stereo amp. Note: many "regular" stereo amps are not dual-mono because the two channels share much circuitry. Theorhetically, dual mono amps should be better (and more expensive) than regular stereo amps.

Dual-mono amps are pretty much by definition also fully balanced as each half of the dual-mono amp has identical but separate circuitry. But, as Swampwalker said, stereo amps can have balanced terminals (XLR) without actually being a fully balanced design at all.

Some fully balanced components don't have RCA outputs, ie BAT (I think), but most fully balanced components have both XLR and RCA outputs and inputs just for convenience (and saleability?). Finally, any stereo component can be fully balanced because they have two channels, ie transports, DACs, pre-amps, as well as amps. If you believe in balanced construction, it's probably best when used on all components in the system. Personally, I have all fully balanced components but prefer RCA ICs-- just my preference. There is no consensus as to which is better-- XLR (balanced) or RCA (single ended), and each has it's proponents. Good Luck. Craig