How to get the best Phono Signal?

[brit]

It has been speculated in this thread that there may be a difference in the quality / hiss level of the phono stage in various Devialet amps.

OK, with respect to preferences between different external phono stages, this is in part subjective and may be system dependant, all of which is fair enough.

However, the hiss level is easily measurable with a smart phone dB app or similar.  It looks like it might be a dull and wet weekend here in the UK, so something to try if you have some time?  I think it might be interesting if we could establish that there are significant / measurable differences between the phono stages in different amps.

This is a check I performed with an iPhone app tried a while back:

Turn the amp on, select phono, at -40dB, all is quiet.  Up the volume to 0dB and you can hear the hiss very clearly.  Using an iPhone app and the phone roughly in the listening position, it recorded about 36dB as background silence (silence is quite noisy in terms of dB's)  Upping the volume until the app reached 50dB, I checked the Dev and it was on about +2dB

Hi @Confused. Just for clarity, what App are you using to conduct this check?


David