Someone linked me to a thread on the Famitracker forum;
http://famitracker.shoodot.net/forum/posts.php?id=763&pid=5940#5940
Which is not technically correct.
Auto-echo can be used on both square-wave channels, simultaneously, with different settings (level, delay etc.) on each channel.
Also, it isn’t much of a CPU strain but it’s correct to say that it uses (relatively, in terms of how much the NES has) a lot of RAM.
Just thought I’d clear that up.
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