Output gain on Seed from Pd patch

I’m managing to get some Pd patches running on my Seed now, it’s lots of fun.

One funny thing I’ve noticed: the output gain from the Seed does not seem to correspond to the Pd patches at all. If I just make a simple sine tone patch and play it out my Seed it will distort significantly unless I reduce the gain by 90% (using the [*~] object).

I’ve found that I need to really lower the output of all of my patches in order for them to sound ok on the Seed.

I’m wondering if there’s some kind of control for output gain on the Seed that I’m missing? or something else entirely?

an update on this. I thought I’d have a look at the actual output that the Pd is generating, here’s a screenshot. This is the level of volume that I have to send in order to not start distorting on the Daisy output. The max value of that output wave is something like 0.04.

This seems rather extreme, surely this isn’t right?

That is pretty strange. It might be worth attaching a patch here (even if it’s super simple!) so I can take a look and see what might be going on.

I’d definitely appreciate someone else having a look! The patches and stuff are here.

I’ve started to wonder whether it’s related to another post I made here recently, about noise on the audio output: Noise on audio output - #3 by yannseznec (you’ll see the link to the patches on there too)

@yannseznec So I tested your patches on my seed Rev4 and Rev5, and was able to increase the gain on the simpleSynth until the output reached 1V RMS without clipping (basically just removed the *~.2 and *~ .3 and the volume pulsing stages). You may be facing a hardware issue if you’re not able to push the gain that high. The seed can exhibit some digital noise if your output level is very low.

@Corvus_Prudens thanks for testing!

So I guess it could be an issue with the board, though that seems odd to me. I have a second Daisy Seed I can test just to be sure.

Otherwise, I’m concerned that I’m just making some really basic mistake. Is there no master output gain control that I can set somehow? And am I correct to just be connecting my headphone socket directly to pins 18/19/20?

@yannseznec Oh yeah so connecting headphones directly to the audio out pins could easily cause distortion. The voltage on those pins at 1Vrms is around 2.8 volts from peak to peak. I think most headphones are meant to receive voltages around 10 times less than that. If your headphones aren’t too low impedance, you could just set up a voltage divider on the output to get better signal to noise on it. Normally you’d just feed the signal into an interface that can handle line-level voltages though.