ORIGINAL: Rodney
Right now many JR's and Berg's are single conversion and better than a lot of dual conversion receivers.
The quality of a receiver is in sensitivity ratings and in noise immunity which can be achieved by good design by either technique. In short, whether a receiver is dual conversion or single conversion has nothing to do with it's quality or performance.
Actually, a bunch of radios aren't "conversion" filtering at all.
Just because a radio doesn't say "double conversion" anywhere on it doesn't mean it is a single conversion. There are other filtering strategies than "coversion", single or double.
Truth is, you don't convert the mass of signals that comes down the RX antenna, you FILTER them to pick out the single one you want. The term conversion is an advertising one. Used by the people who figured if they took a "single conversion" that wasn't good enough for longrange work and ran the still junky signal back through the same process that hadn't cleaned it up good enough before, that it'd be something worth advertising.