[sdiy] THAT2180A

[Tom Wiltshire]

> On 29 Nov 2020, at 04:54, drheqx <drheqx at gmail.com> wrote:
> 
> Thank you Tom. The DAC idea is really cool. It's true, performance will dictate performance. I can get away with less noise performance here but the linearity is important. Some of these pan circuits have a bump in the middle or a dip. I'll have to work that part out. This is something where a musician would certainly notice that bump. 

I did, and I’m no great musician.

On circuits with the bump the sound seems to get nearer as you pan it across the spectrum, like the sound moves along a straight line from left to right just in front of you, so the centre point is much closer than the far ends of the line. On other circuits, you get the opposite effect, where the centre dips and the signal seems to disappear into the distance, so it spins from by your left ear, to miles in front of you, round to by your right ear. Neither sounds “even”. The ideal is something that gives a sound that seems to rotate around you with you at the centre, not moving closer or further away. The exact listening set-up obviously will affect how that illusion is to be created, but the aim is pretty clear.