The Absolute Sound disects SAM

[David A]

Your issue may be relating to this bug for current firmware + SAM + tone adjustment: https://devialetchat.com/Thread-Bug-for-...-DOS-2-2-4.

Did you ask your questions to Devialet team?

I don't think the bug you mentioned is my problem. What I'm hearing depends on the SAM % setting and occurs with Bass set to zero (I  always run with Bass and Treble set to zero). It becomes more noticeable as the SAM setting is increased.

I haven't tried asking Devialet, basically because I tend to run with SAM either set to 0% or extremely low, less than 10%, when I don't notice it, or I use a configuration file with no SAM parameters. I don't feel a need for increased bass extension with the Sopra 2's in my room with the music I listen to but the correction applied at the 0% setting does produce a difference I like.

I don't feel a desire to have Devialet really change anything because I can get a result I like with things as they are. I'd hate them to find a bug on the basis of a report from me, fix it, and then find that I don't like the result after the fix. As I said, I'd like to have a better understanding of what's going on, what is changing in the SAM DSP processing as you change the SAM setting and also as you change volume.

I just re-read the comments on SAM in Jim Austin's review of the 140 Pro in December's Stereophile. He reports measuring an increase in SPL at some—not all—pure tone test signals with SAM turned on and he asked Devialet about that. Their response was that it had to do with room interactions which he said he didn't understand but that dialling SAM back to below 40% solved the problem. That sounds like he could have been noticing a similar issue to the one I notice. I think I can understand how it could be a room interaction. If the SAM % setting dials in an increasing amount of bass boost over the range covered by SAM, the increased level at some frequencies could be exciting a room mode and if that is the case, reducing the setting could well reduce the noticeability of the issue. If that's the case then there's nothing for Devialet to "fix" in my case, I just have a room mode at a frequency in the lower range of female voices that is being excited to a level I notice once I increase my SAM setting to somewhere around 10-15%. Anyone else who doesn't have a room mode at that frequency isn't going to notice what I'm hearing and there's no bug to fix, it's likely to be a standing mode issue in my room. The problem that I have is that Devialet just seem to like to not give people the information they would like to have  and, given that they weren't all that forthcoming with information when asked a very specific question by Stereophile's editor who was reviewing one of their amps, I really can't see them giving any more information to "mere owners" like you or I. People have been asking them questions about SAM for a few years now and we still really don't know much more than what they initially told people when they introduced it. They simply don't like providing information.