THE A-A6 has had to scrap for its five stars every time we've reviewed it. Most equipment that attracts the number of criticisms that we've levelled at the Pioneer ends up with a four-star verdict and, occasionally, we've fretted that perhaps the A-A6 wasn't worthy of the full five. Lined up in a Group Test for the first time, though, we're relieved to find that we were right all along - this is a five-star amplifier, but it's not without shortcomings.