23-Nov-2016, 16:37
(20-Nov-2016, 14:14)Confused Wrote: OK - I have just been trying the 'Gui' test. (Per #53 above)
Very interesting! I used the Devialet remote pseudo blind test, that is you repeatedly press the SAM on / off button to the point that you do not know if it is on or off, sat in the listening position I cannot see the display on the Devialet. I did manage to find a number of recordings with more or less zero bass as suggested, all 24 bit and decent recordings. Toggling SAM on and off I, I could tell a difference between each one. In terms of details, I could notice a very slight improvement / reduction in the fine details. The first couple of time I checked, the slightly better details were obtained with SAM off. I was able to repeat this a number of times, there was one occasion where I preferred the SAM on version, but other than that, each time SAM off prevailed. I recall YabaVR (Gui) posting that SAM 'looses all the fine details'. I would not put it as starkly as this, for me it was a very small reduction in fine details, very small but clearly discernible. As for soundstage, this was a bit hit and miss for me, so I reckon this aspect may be more system / listener specific. Sometime I preferred the soundstage with SAM on, but I think a fairly consistent result was a narrowing of the soundstage, which in same cases I think I may have preferred as it came across as a more accurate sound stage, possible because it was actually less accurate! So yes, definitely a ***** (replace ***** with insignificant, small, major / unacceptable, depending on your perspective) loss of details. I think the sound stage effect could be system dependant, but in my case it was a narrower sound stage that perhaps seamed more precise and more detached from the speakers, which could mean more mono!
Well done to Gui for spotting this and posting such a clear method of trying it for yourself.
Being slightly less serious (although there may be a serious point lurking here), I can now propose the Confused SAM test. This is for the very brave only. Play the first 30 seconds of Dizzee Rascal's 'Dirtee Disco' on a reasonable volume. Please note that it is neither safe nor sensible to play more than 30 seconds of this track. I suspect that Confused SAM test may also be very system dependant.
I just gave this a try, I didn't find it easy finding recordings that fit the requirement, most solo female vocals recorded in a big acoustic have ambient grunge going on low down that SAM reproduces more accurately, and expands the soundstage as I would expect, studio recordings don't have much acoustic space present, and it's likely to have been through so much processing as to be unreliable. However I never found less soundstage or detail in any track with SAM on, often the opposite, and I always prefered the with SAM version overall. This makes sense to me, part of the female vocal range is within the operating frequencies of SAM.
PS Maybe all of what I tested can be discarded because I did the Confused test first.
Roon, Rega P9 + Dynavector XX2Mk2 > 440 Pro > Sonus Faber Guarneri Evolution