Axe FX III SPDIF louder than expected - not unity gain???

[Orvillain]

I don't know if I'm doing something wrong or what.... but I have the Axe3 connected to my Quantum via SPDIF. I'm sending a synth to the Axe3 and the peak level is -22.3dBFS as shown on Reapers meters. I then patch this through Axe Edit from Input 4 straight through to Output 2, and what I get back is a level that is -4.3dBFS - 18dB louder than the input signal.

I am not sure why this is? I would've expected in such a situation that the SPDIF signal would be unity gain ????

You can see the meters here show the level disparity.

The level on the input block is set to 0.0dB. The levels on the output block are all set to 0.0dB. The AES/SPDIF level in the I/O setup is set to 0.0dB.

Changing Output 2's level (-10 or +4) makes no difference. Using Output 1 as the digital assignment makes no difference.

Anyone have any on this??? @FractalAudio ???

Is this just by design and I should set the AES/SPDIF level to -18dB to get unity gain??

 

[James Freeman]

Output 2, Output Level "-10 dBV" change it to something else.

 

[Orvillain]

Output 2, Output Level "-10 dBV" change it to something else.

Doesn't make any difference to the digital side of things. Only analog. From what I can tell.

 

[Orvillain]

Ahhhhhhhhhhh... the plot thickenario!

Unity Gain

Something doesn't make sense about this. If you start with the 4CM test preset and bypass the amp's loop (I'd probably also unplug the cables from the amp fx send/return) you'll end up with the same signal path as a 2CM test preset. Does that actually change the level hitting the preamp? It...

forum.fractalaudio.com

GlennO says:

AFAIK, It's not documented anywhere, but outputs 1 and 2 add 18 dB to the output. So, if you set the level in the 1 and 2 output blocks to -18 dB, those outputs will work the the same as outputs 3 and 4.

So it would make sense then, if this 18dB is being applied both to the digital I/O (when assigned to output 1 or 2) as well as the analog.