Chord Dave vs. DAC-V1

hope this gets resolved soon.....

did you try turning the balance left to right and back?

Yes, one side works fine, turning the balance dial to the other side ends up mute....

Hi any update?

I sent the unit back to my dealer, they opened up both the NAC552 and the 552PS and with the help of the Naim support folks apparently determined that the issue is related to a dead discreet regulator in the 552PS, there is no word on what caused this and the feedback is that this is an extremely rare case. Naim shipped a replacement regulator which the dealer will fit into the 552PS next week and hopefully this fixes the issue.

I am very curious if anyone else had a blown DR, what would cause it? electricity issue or simply a faulty component (simple bad luck).. What could I do to prevent this from happening? I did a bit of research on power conditioners, etc. and from what I gather these are a "no-no" with Naim equipment and may do more harm to sound quality than benefit...

Opinions welcome....

I think it is a very rare one off case, nothing to worry about. I've owned many Naim kit since 2010 and never did anything fail.

Much respect to Naim and your dealer for solving this so quickly. I wouldn't worry about it with such great customer service.

Yep, I am fortunate I have a good dealer that has been pretty helpful, I just hope the diagnostics are correct and that indeed it the DR at fault, I also hope this kind of repair does not require any special re-calibration, or any other "Factory only" post-maintenance wizardry to ensure proper operation and sound quality post repair... Will keep you posted, next week we will know if it is really the DR that blew.

No - repairs to the PSU, do not require any special calibration. 

Your dealer has recapped (serviced) many Naim power amps and power supplies for many years.

Going back to the Naim sound my brother when he worked at Heybrook .... did an extensive study into the sound of op amps... they all had a superflat frequency response...but they all sounded different...allot were based around hot versions of the industry std cheap op amp can't remember the ref number.... my brothers investigations led him to believe that the earthing  and the ancillary supplies were fundamental .... to getting good performance. I think Naim has pushed this to the limit with their circuits....with good results... there is definitely a naim signature...and the substitution of the 552 with the Dave goes to prove it.... I heard it at the Bristol hi fi show.... Dave direct into Nap300 = disappointing results...

Given that it is the same Dave output and the same 300 input in both scenarios, the difference being direct path vs through the 552, I'm not sure that the difference proves that either grounding or power supply with the 552 are the significant factors. (And as an aside, the 300 presumably has similar attention to detail re grounding and PS .)

Either i) the 552 is itself changing something in the sound, or ii) the 300's behaviour is being affected by the source (552 differently from Dave), or iii) Dave is being affected by the amp (552 differently from the 300).

Some people have suggested that performance of Naim power amps is affected in some way by being used with a Naim preamp. One suggestion as to the reason is a high frequency filter in the preamp, preventing any adverse effect in the power amp if very high supersonic frequencies are present - however Dave does likewise. Another suggestion has been "impedance matching", but I don't see that as likely in this instance: The 552 has a quoted output impedance of <50Ω (though unclear if this means close to 50 or a lot lower), while Dave has a quoted output impedance of 5.5mΩ. With an input impedance of 18kΩ I would not expect the 300 to be adversely affected by a source impedance lower than that of the 552 (cause ii above). With Dave's very low output impedance I would not expect it to be affected by connection either to the 300 or to the 552 (47kΩ) or the 300 (18kΩ), and the 552 quotes a minimum load impedance of 10kΩ so I would not expect it to be affected by the 300 (cause iii above).

These all suggest that in the difference between direct connection or through the 552,  the 552 is doing something in its added circuitry that is modifying the sound - or is there something I have missed?

This is what I was getting at .... the circuit layout and its earthing strategy do effect the sound perceived .... not the classic measured frequency response ......... music is transient in presentation - how the amplifier deals with this imparts a characteristic to the sound .... so I think the 552 does do that, as would any amplifier.... however, it is a question of degree and presentation....I suspect the perceived quality has been carefully engineered by Naim.... and the earlier this injected into the system the more impact it will have when further amplified by the power amp. The Chord amp within the Dac will have been engineered - differently. ..... 

Michael Fremer noted the same sort of thing back in the 2003 Stereophile review (Google 'Stereophile NAC552' ) of the 552. 

Richieroo posted:

This is what I was getting at .... the circuit layout and its earthing strategy do effect the sound perceived .... not the classic measured frequency response ......... music is transient in presentation - how the amplifier deals with this imparts a characteristic to the sound .... so I think the 552 does do that, as would any amplifier.... however, it is a question of degree and presentation....I suspect the perceived quality has been carefully engineered by Naim.... and the earlier this injected into the system the more impact it will have when further amplified by the power amp. The Chord amp within the Dac will have been engineered - differently. ..... 

However a preamp can't add sound quality, though it can modify the sound - i.e filter it, shape it, colour, whatever term might be appropriate - so that it sounds different, and of course that might be perceived by a listener as a beneficial change (or not). The 552 in this scenario is not replacing Dave's internal amp, as it is the same output that goes to either the 552 or to the 300, so whatever Dave's internal amp that might have been engineered to do "differently" is still happening when played through a preamp.

Innocent Bystander posted:

However a preamp can't add sound quality, though it can modify the sound - i.e filter it, shape it, colour, whatever term might be appropriate - so that it sounds different, and of course that might be perceived by a listener as a beneficial change (or not). 

 

Exactly. Some like their music with a bit more seasoning. 

james n posted:

Innocent Bystander posted:

However a preamp can't add sound quality, though it can modify the sound - i.e filter it, shape it, colour, whatever term might be appropriate - so that it sounds different, and of course that might be perceived by a listener as a beneficial change (or not). 

 

Exactly. Some like their music with a bit more seasoning. 

Seasoning: I like that, it is a very apt simile! I might like something far less (or more) salty than the next person (ditto degrees of heat if it is a chilli dish etc): it doesn't make either right or wrong.   ...although if produced by a good chef, only the one he or she tasted and seasoned will be what the artist created.

Ok ... I see what you are saying ....however,  if you plug it into 552 the poweramp will still be influenced by 552 .....  or 252,272 etc... and influenced/shaped. The lack of the 'right shape' is very apparent when the Dave drives the NAP300 direct..... to me it sounds flat and un-dynamic. I know what you are suggesting ..... see Thijazi comments.......

Innocent Bystander posted:

james n posted:

Innocent Bystander posted:

However a preamp can't add sound quality, though it can modify the sound - i.e filter it, shape it, colour, whatever term might be appropriate - so that it sounds different, and of course that might be perceived by a listener as a beneficial change (or not). 

 

Exactly. Some like their music with a bit more seasoning. 

Seasoning: I like that, it is a very apt simile! I might like something far less (or more) salty than the next person (ditto degrees of heat if it is a chilli dish etc): it doesn't make either right or wrong.   ...although if produced by a good chef, only the one he or she tasted and seasoned will be what the artist created.

Or rather metaphor!

Well about a month and a half later, I finally have my NAC552 back (it was sent back to the UK for repairs, apparently one of the channels went on permanent mute due to a faulty relay as rare as that is).

During this time I had the Chord Dave hooked up directly to the NAP300 so I really got an extensive listening experience while I waited for the NAC to be fixed, the results are two-fold:

1- The level of improvement with the NAC is huge, the Chord Dave sounded good, but never managed to get me to enjoy the music as much, it tired me after a while and always felt flat compared to my older setup. For any doubters out there (many asked me to test this), the NAC is far superior, once I hooked it back into my system it was a massive improvement even totally cold. Brought a big grin on my face!

2- The flip side of all of this was that I now feel once more as if I just upgraded , I get the fun factor and the excitement of setting up the NAC552 for the first time all over again with the same investment.

The only thing I did note is that the NAC is sounding a little edgy and stressed with some music that I always listen to, and while I am a huge sceptic of the notion that these boxes need "burn in and warm up" time that would impact sound, it may just be the case that the NAC will go back to its old paces once it has been up and running for a few weeks, we will see.... maybe this also proves another theory.

Cheers,

Tareq

Hi Thijazi ... I have just got a 552 and NDS ... it made a huge difference it is as if everything is illuminated, more open and rhythmically charged - compared with the 272-555ps.

Enjoy them....best pre and a very good dac..

Try Dave with a pair of headphones aş well, it might be a very good experience

Yeah, funny enough I never bothered plug my headphones into the Dave! well something new to do over the weekend....

 the headphone output of DAVE is extremely good, performance is off the charts.

analogmusic posted:

 the headphone output of DAVE is extremely good, performance is off the charts.

I have recently returned to headphone listening this past fall after a 15 year absence.  I returned to headfi.com after last patrolling those forums in 2003/04 - my have things changed! 

On headfi.com the Dave is universally acknowledged as the pinnacle of the DAC/headphone amp world.  It is the equivalent of the 552 for headphone users.

PS - the same goes with the new Utopia headphone introduced by Naim's partner Focal last summer.  More or less universally acknowledged as a dramatic game changer.  I own a pair and it is a truly amazing piece of engineering.

I have been trying to find out what are the factory-default settings for the Chord Dave, and cannot seem to locate this info anywhere, keen to know what is the default HF Filter setting and what is the default Phase setting... Anyone here?

thijazi posted:

I have been trying to find out what are the factory-default settings for the Chord Dave, and cannot seem to locate this info anywhere, keen to know what is the default HF Filter setting and what is the default Phase setting... Anyone here?

my copy of the manual says this:

HF Filter On or Off – This turns on a sharp high frequency cutoff filter set at 60kHz. This filter bandwidth limits higher sample rate recordings to reduce noise shaper noise from the ADC. You may find that the noise will degrade the sound quality by increasing noise floor modulation as the out of bandwidth noise causes intermodulation distortion with the wanted audio signal in the analogue electronics. By activating the HF Filter it is likely that you will hear a positive effect upon the resulting sound quality.

Phase Pos or Neg – You can optimise the absolute signal phase on the analogue outputs to positive or negative.

If I recall correctly the menu gives simple choices of on or off for each. But if you mean how is it set up when first received from the factory, I'm afraid I can't remember -phase probably positive, but filter less obvious - and either is guesswork.