Just wondering, since you have it set for fixed volume, is it fixed at 0dB or -20?

Y'all should hear the M51 with the UpTone usb REGEN in place. Didn't think the M51 could be improved upon and that I'd quickly sell the REGEN off to recoup the cost. I was wrong. Very wrong.

barid said:

  New NAD M51 addition to the mix this week.  This is an interesting DAC.  Definitely laid back, vocals sounds a bit soft.  Edges seem blunted/rounded.  Might take me some getting used to coming from the Benchmark
 

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That's a nice looking stack. Give it time for yours ears to adjust. You could very well find that the sound you were previously accustomed to is thin and abrasive compared to the M51's presentation. Happy listening.

eddie q said:

Just wondering, since you have it set for fixed volume, is it fixed at 0dB or -20?

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After the factory reset, my fixed volume went down from -10 to -20db , If I want to match my gumby volume I stay at -1/0 db (guesstimated by ear not using any meter)

Hi, I am new to this site and forum and wanted to introduce myself and pass some past experience with you guys.
 
I have owned my m 51 for over 2 years and that had the older zetex chip. Recently I had an issue with it and ended up getting a new one from crutchfield and was told to send the old one back to them after receiving the new one. After inspection of the new dac it had the newer CSRA6601 chip in it.
 
Of course, I was excited to compare the two! For the comparison I put them side by side and just swapped the interconnects from one another leading to my Pass Labs xa30.5. While the older zetex chip dac has over 2 years on it and did not even burn it the brand new  CSRA6601 dac and had basically no burn in.
 
The results where interesting. It was very clear that the new dac with the CSRA6601 chip was a far superior chip. Better clarity and detail where quite obvious and it did not even have any burn it time on it.
 
So it seems clear to my ears they did put a better chip in it when the made the change. So those looking for a used one may want to consider the one with the newer chip in it.

Were both dacs using the same firmware?

I believe the older dac was 1.42. I know it was not 1.39 as I hoped it did when I checked. The new one I thought would have 1.50 being it was so new but it was a quite old firmware. I will have to check it again but it may be the firmware that was put out after the older dacs 1.42. Perhaps 1.43 or so.
 
Sounds like from reading this forum all the firmware in the 1.40's all sound similar. If my memory serves me 1.39 is the main firmware that has the best sound.

Hello guys I'm new to this forum,
I could use some help,
I've reset the M51 to factory settings but I can't get the volume to go above +10db. where-as it goes to -90db ?
I want to test the pre-amp driving my Roksan Caspian M2 power amp.
I'll be very grateful for a pointer
apologies if this has been covered before
Cheers
Alex

The NAD M51 is not supposed to be driven beyond 0dB.  If you're using this as a preamp, then it seems that the power amp needs more than 2 volts rms to drive it at full volume.

Forgot to ask, have you hooked up the amp to the m51?  If not, first drop the volume to -40dB before playing music.  Only afterward should you turn up the volume.
 
If all the gear is working optimally ramping the volume up closer to 0 outta give you full power from the amp.  

eddie q said:

  Forgot to ask, have you hooked up the amp to the m51?  If not, first drop the volume to -40dB before playing music.  Only afterward should you turn up the volume.
 
If all the gear is working optimally ramping the volume up closer to 0 outta give you full power from the amp.  

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Yes I had the amp hooked up to the M51
I'll try taking your advice and drop it to -40db before switching the power amp on
Is it just me or what other kind of digital pre-amp behaves like this LOL
Thanks

alexxander said:

 

eddie q said:

  Forgot to ask, have you hooked up the amp to the m51?  If not, first drop the volume to -40dB before playing music.  Only afterward should you turn up the volume.
 
If all the gear is working optimally ramping the volume up closer to 0 outta give you full power from the amp.  

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Yes I had the amp hooked up to the M51
I'll try taking your advice and drop it to -40db before switching the power amp on
Is it just me or what other kind of digital pre-amp behaves like this LOL
Thanks

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Short answer:  The use of negative values denote attenuation.  In an ideal world of dBFS (Decibel Full-Scale), 0dB would be considered Unity.  That's where the signal is not amplified nor attenuated.  Positive values denote amplification from unity and negative numbers denote attenuation.
 
In a more fun way of seeing it, max loudness will be a "10" (0dbFS), and pushing it to "11" would be a positive value in the dBFS scale.
 
The dBFS scale This method is widely used in broadcast television and video editing (the field I'm familiar with).
 
Hope this helps 

eddie q said:

  Short answer:  The use of negative values denote attenuation.  In an ideal world of dBFS (Decibel Full-Scale), 0dB would be considered Unity.  That's where the signal is not amplified nor attenuated.  Positive values denote amplification from unity and negative numbers denote attenuation.
 
In a more fun way of seeing it, max loudness will be a "10" (0dbFS), and pushing it to "11" would be a positive value in the dBFS scale.
 
The dBFS scale This method is widely used in broadcast television and video editing (the field I'm familiar with).
 
Hope this helps 

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mmm .... sorry not getting it, it'll take a wee while to sink in lol
I'm an old guy and a bit slow on the up take.
please explain why at 0db i hear nothing through my old floorstanders (Definitive tech. Mythos1) and at 10db it's still only barely audible?
thanks

alexxander said:

 
mmm .... sorry not getting it, it'll take a wee while to sink in lol
I'm an old guy and a bit slow on the up take.
please explain why at 0db i hear nothing through my old floorstanders (Definitive tech. Mythos1) and at 10db it's still only barely audible?
thanks

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Because all preamps act as attenuator between power amplifiers and sources (for example CD player). At 0 db (no attenuation) it is supposed to play at full power (maximum loud level). So preamp is needed to lower the volume.
If you hear nothing at 0db (set in NAD) and only silent sound at +10 db then you probably messed something up. Maybe you do not have power amplifier but integrated amplifier with its own preamp that is set to low volume and you connected NAD to "line in" (pre amp input) and not to "main in" (power amp input) in your roksan...

Roksan M2 power amp has inputs and outputs on both RCA and XLR connectors.
Did you plug the interconnect cables in the input connectors of the amp?
There's a switch between the XLRs and RCAs to select which type of inputs you want to use.
Check if the right one is selected.