SNR and Dynamic Range... Myth??

[Mercuri]

This has been a debate between myself certain gear manufacturers and retailers...

Is it safe to assume that, under perfect conditions (balanced power, no radio interference, etc.) a unit can live up to it's published specs for noise and dynamics?

Example: If I grab a Mytek A/D rack, can I punch "Record", analyze the output, and really, REALLY just see the little bar floating care-free right around the -120dB mark? Assuming there is a device connected that has a SNR of at MOST -120dB?

Curious... Anyone?

[Schizzo]

!!!!!PUSH PUSH PUSH!!!!!
!!!!!!!!
!!!!Nearly 9 years later!!!!

[ajbianco]

Originally Posted by Mercuri

This has been a debate between myself certain gear manufacturers and retailers...

Is it safe to assume that, under perfect conditions (balanced power, no radio interference, etc.) a unit can live up to it's published specs for noise and dynamics?

Example: If I grab a Mytek A/D rack, can I punch "Record", analyze the output, and really, REALLY just see the little bar floating care-free right around the -120dB mark? Assuming there is a device connected that has a SNR of at MOST -120dB?

Curious... Anyone?

at what sample rate are you talking about? i have mytek 192s. if i set the frequency to 192 the noise level is sitting on -80. however apparently this is just out of band noise because of the chips used on the main board...

[lukejs]

I was wondering the same thing. After I bought my Apogee AD16-x, I was wondering why my levels from my Lynx inteface mixer were all hovering around -80 with my preamps connected, and even for channels where nothing was connected, I never saw levels dip down to -120 where I figured they'd be since the specs on the AD16-x give it a 120 db signal to noise ratio. Apparently there is noise in the sub and supersonic range that causes this.. I've heard of this with the Echo Audiofire line as well, where this noise is seen on the meters but is imperceptible to the ear...

[timlloyd]

You do know that the OP is from 9 years ago don't you?

But regardless, and assuming that equipment has been connected up correctly etc. you're not always going to achieve performance that matches the published specs simply because sometimes published specs are produced by measuring under unrealistic conditions ...

So yeah, re. the OP - if the published specs are realistic and accurately measured, then it's not unreasonable to expect to be able to reproduce them.

if

[myles]

Please don't tell me you're using the meters in Pro Tools for this snipe hunt...

[timlloyd]

lol

[dkelley]

Originally Posted by Schizzo

!!!!!PUSH PUSH PUSH!!!!!
!!!!!!!!
!!!!Nearly 9 years later!!!!

hahhaa you're crazy :-)

[dkelley]

Originally Posted by timlloyd

So yeah, re. the OP

if the OP is still alive and on GS

[lukejs]

9 years later !!! OMG !!!!! But the problem still exists !!! The meters are showing noise, that I can't hear !!!!!!!!!!!!!! hahhahahaha

[mobius.media]

Username: Mercuri
Last Activity: 27th May 2003 11:19 PM



Anyway, if you want to test your converters, just do a loopback - connect the output of one channel to the input of another with a short cable and record without any music going out. You can analyze the noise floor of the resulting 'silent' track to your heart's content.

You can also use RMAA to do the analysis for you. In my experience, the noise floor specs are usually about 5-6 dB higher than what manufacturers claim.