Not sure what those words mean. But it doesn't matter since we both have the schematic to look at.
Anyway, what features do you want to compare? Cost, gain-bandwidth, input impedance, quiescent current, noise figure, reliability, stability, ... There are lots of specs for amplifiers.
Sorry - it seems That I have not expressed myself in a clear manner.Look at Link Removed. Everyone of those transistors has a purpose.
The situation is as follows:
Wenn I want to realize a differential amplifier there are, of course, several options. Such a situation is quite normal in analog electronics (e.g. active filters, oscillators,...).
* In the case under discussion we have a novel circuit (Baluncore`s circuit, post#22) which provides a single-ended output with a very low output resistance (opamp output).
This one of the advantages if compared with the well-known two-transistor circuit without this opamp (long-tailed pair, first stage of Baluncore`s circuit).
* However, there is a well-known opamp circuit (with 4 external resistors) that also can provide such a low-resistive single-ended output.
* And my question was if it makes sense to compare these two circuits which each other, as far as some important parameters are concerned - for example: Input resistances, linearity, dynamic stability, gain restrictions, CMRR, accuracy requirements (symmetry), ...(just to collect some thoughts of forum members who are interested).
* I have mentioned already one restriction: Due to active feedback (feedback factor can be above unity) the differential gain of Baluncore`s circuit (post#22) must not be too low (a gain of two leads to instability).