Audio input level

The product page for the Akso says the audio input is line level - does that mean we would need a preamp to connect something like a guitar?

Hey @rfb.

Yes, a preamp with line level output is going to be the quickest way to get a guitar or mic going.

There is actually some amount of gain available from the codec’s PGA though:

Up to +55.25dB at the absolute max which back of the envelope might actually be enough to be interesting but the control is pretty coarse: you get six bits of resolution for the range -12dB - +35.25dB and then the +20db is either on or off.

We need to run an experiment with a guitar jacked in directly to see how usable this could be. It may be something that has been done before on the original Core hardware; I can’t remember off the top of my head.

I think it’s definitely going to be usable for more abstract “guitar as synth patch controller” sorts of applications. It’s an open question if it could be good enough for a direct pedal application or not.

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I ran a guitar through the old core for a couple years and it worked great.

The guitar is never not going through the axoloti. I think I’m using a preamp in this case but have used it without

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That song could use some Don van Vliet.

I really like where it goes at 4:17.


Great track! The guitar seems pretty clean however! What is the Axo role in shaping the sound?

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Oops just posted the general album.

On THIS track around the 2 minute mark and THIS track around 3:20 you can hear some stutter effects as well as some buffer mangling weirdness.

In the patch the guitar signal goes through an EQ and a compressor before anything else and then through some other triggered effects.

*Edited for clarity

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…same here, worked fine!

anyway, I wonder if the ‘gain’ is actually analogue gain BEFORE the AD- converter,
or just digital ‘makeup-gain’ BEHIND the AD?
I had to set the ‘audioinconfig’ - object to +6 db to match the guitar’s output,
which should correspond to loosing 2 bits of dynamic range compared to ‘plain’ 0db
(IF ‘gain’ was BEHIND the AD)

@rbrt This PGA gain is pre-ADC in the analog domain but is under digital control. The config objects are setting bits in the codec to adjust the gain. The ADC is shown on the right side of the diagram above.