Rrog, just because you tried numerous times doesn't mean you ever tried a combination that was suitable for the purpose. There is absolutely no reason a source component can't have an output stage that is capable of driving an amp directly and many do. Having a 7 Volt output is only part of the story since it could also have a high output impedance and therefore be incapable of properly driving a low impedance passive and/or amp. No disrespect intended but statements like yours which fail to properly explore all of the facets involved and dismiss topologies which are proven to work when properly implemented only add to the confusion of those who are trying to get the big picture.
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