Hello, I came to correct a comment I made a long time ago, and I came across your comment. I had the same impression and I mentioned it a long time ago, but I was wrong. It is that I had not seen the comments of JohnYang explaining certain things.
You can turn the volume knob from L30 to the maximum, by 0db and you will get the same result you got before with your E30 + speakers. Try and confirm.
First of all, L30 uses a logarithmic scale / audio setting, so for example 12 o'clock is NOT half volume.
Maximizing the potentiometer to L30 does NOT introduce distortion. On the board, L30 is set to 0dB with the volume potentiometer at maximum. So there is no distortion.
The amplifier does NOT break a sweat at maximum volume. So feel free to maximize it, without fear. The distortion will not increase.
Technically, 0dB is the best performance setting. Typically -9dB is to provide a more usable volume range for sensitive IEMs, 9dB is to provide more power for headphones that just can't get enough volume at 0dB max volume.
Try using L30 (0db knob max) + speakers at the volume you used before, and you should get the same results as when you didn't use the L30.
When I made my unfortunate comment, I was expecting E30 (DAC mode) + L30 (at 12 o'clock) + powered speakers to give the same result as E30 (DAC mode) + powered speakers. Which was stupid of me.
Now I can confirm that I have been listening to E30 (DAC mode) + L30 (max knob at 0db) + amplified speakers for months, and there is no distortion of any kind, and the volume is the same as if I were listening to E30 + Speakers.
I can't edit my old comment, but I felt compelled to correct it so as not to confuse anyone.
Cheers
MY old comment that he no longer agreed with was this:
https://www.audiosciencereview.com/...ne-amplifier-review.15226/page-68#post-525095