I recently upgraded from a Khadas Tone Board to a Soekris 1321. I noticed that the Soekris clips on some of my obnoxiously loud music, forcing me to turn the volume down a few clicks. I am 99% confident that the Soekris was at 0 dB on the volume. I was using WASAPI on Foobar2000 with no active EQ.
That got me wondering, can simple DACs without volume controls clip like this as well?
A DAC really oughtn’t clip in and of itself, it’s input is a well defined digital input. It’s a badly designed DAC if it does.
A DAC can have an output that is “hot” (higher than nominal line level), which can cause an Amp to clip.
But generally even that ought not be an issue, there is a volume pot inline with the line in, so it’s attenuating the incoming signal before amplification.
If the volume gets too high the Amp will clip, the THX 789 was designed to do this with balanced inputs on High gain.
What was the rest of the chain?
Optical from PC to the DAC then into an Atom headphone amp.
So it’s not the DAC itself clipping then? Just the input signal?
The soekris dac1321 has instructions on setting the line output volume default. Setting that up includes ensuring the clip indicator isn’t flashing while you find the appropriate level. I highly recommend reading over the instructions (pages 4 and 5 on included instructions for the soekris dac1321).
Probably the atom clipping, because the Soekris output is “hotter” than the KTB was.
My DAC has a High/Low output switch, it’s well above nominal line level on High, and some Amps don’t like that.
I take it from this it can clip it’s own output section?
Ugh if that’s true, way to make the user responsible for entirely predictable input behavior.
Yes, but the instructions for finding and setting the default are simple. It literally took me less than a minute to perform. My default has been set from day 1, never having to adjust it once I set it up.
Read it before setting it up. Pretty sure I got that part right.
The amp isn’t clipping (I don’t think), the volume light on the Soekris flashes red when clipping happens. I found that my (very) loud tracks cause that light to flash. I’m wondering if other DACs would clip the same way with the same music, just without indication.
If you set the default and it is still clipping, you may need to go a few clicks lower. Also, make sure you set up the default line out without any of the filters on as this also could be an issue.
I haven’t had to change my 1421 yet for clipping since I set it, but yes just go a bit lower and you should be just fine
I checked those tracks in question with Audacity. There are a lot of parts that hit 0 dBfs.
None of the DAC’s I own do, it seems like an odd design choice. Fundamentally there is a maximum output voltage from the Converter itself when the input is + or -1, being able to clip that in the DAC’s output buffer just seems odd.
I could see doing it for an R2R if the attenuation was digital, allowing it to exceed 1.0 would let you get better accuracy, and the vast majority of recordings aren’t at input maximums except during transients.
When I wrote audio software back in the late 80’s, early 90’s we used the same clipping trick to increase dynamic range when we were stuck with 8bit DAC’s.
I should note clipping like this is audible even if it’s <1% of the samples, but it can sound “better” than the loss in dynamic range.
The DAC itself, no.
Simply for the fact, a digital signal could roll over (as in: overflow) and the analog signal at “all bits = 1” would just be the max voltage the DAC can output.
The Op-Amps and amplifiers downstream from the DAC-chip/circuit however could clip when poorly designed.
I’ve been messing around with the volume control on the Soekris again. There seems to be some “skipping” when clicking the knob slowly.
My original way of setting the volume to reference level was turning it all the way up, then stepping down 10 clicks. I think doing it this way sometimes still leaves me above reference level, causing the clipping on my compressed music.
If I turn the volume more quickly in two groups of 5, the same tracks no longer clip.
That means a click or two aren’t registering properly in one of these scenarios. To satiate my OCD, I’m going to assume it’s the former. Based on what everyone here has been saying, there shouldn’t be any clipping if everything is set correctly.