[Wing]

So I gots me some op amp engineering samples for free (wow) from TI (2132P,2132PA,2604AP) and National Semiconductor(LM6172, 6182). They arrived next day with free UPS next day air (wow!). Popped the X-DAC and started swapping. Initial impressions were the chips sounded softer and more laid back than the NE5532s in there. I had to turn the volume up to match what I had heard before. The NE5532s I would classify as having a big bold sound, forward - what I think lcaudio call an aggressive midrange. I tried all the chips except the LM6182 in various combinations (There were 4 sockets on the DAC) and settled on all 6172s because it was the only sample that had 4 chips. I kept listening to it, then a strange thing happened. The volume seemed to be getting louder and more dynamic as the hour passed by and I had to lower the volume on my amp to a more comfortable level to where it was before I swapped the chips. Has anyone else experienced something like this?

 

[ppl]

This happens to me every time i make a new design or upgrade Chips. I have found that by keeping the unit continiously powered for about 2 weeks will burn the Chips in very well.