TDA2030/2040/2050/LM1875 stability issue with low gain (K=1...3)

AFAIK in some datasheets there was recommended DO NOT lower gain less than K=10
What about real life? Is there any problems with lower gain and can it be fixed by small capacitor across global feedback resistor (from output to negative input in reference schematic) ??
 
The problem is that lower gain means more feedback and less phase margin. You can have low gain by adding a resistor, usually between +in and -in so that the feedback is the same as a 10x gain+. These amps are optimized for 10x gain because that is the typical use, and it improves the slew rate and HF performance. Compensating for unity gain means a larger compensation cap and a slower slew rate.
 
yep and little picky about where DC offset is set.
I dont use lower than 5x and add small cap over feedback

with DC offset, it is a op amp so it is rather easy to use 1% resistor
to set DC on output very very low.
For some reason stability less a issue when offset is set high around
common 2mv to 3mv. If dialed in very low around 500u then they seem
to be more unstable at higher power levels.
 
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