Sure, but in such a case if protection circuitry has blown, and the supplied PSU is operating fine and its protection circuitry hasn’t blown… then that would indicate a different non compliant power source had been used, and repair would be chargeable. I know other manufacturers do this, and many many years ago I had personal experience of that with Sharp Electronics.
I seem to remember the first time I had my Hugo repaired by Chord (the internal power regulator looked like it failed … but it was the internal batteries, before we knew they needed replacing every few years which I now do myself)I needed to return the PSU with the Hugo.
Sinc-M, Sinc-M, LNS15.
M
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I tried the 3v output. The source is an Innuos Zen running Lyrion (Logitech) Music Server. I tried first with the Innuos player setup to apply no volume gain (through LMS settings). At first I used the Chord power supply and later swapped it for the MCRU power supply. The sound had more detail and was a little bit lighter in the bass, more noticeably so with the MCRU supply. The difference brought about by the filter settings were more obvious to me with the 3v output. I have no way of ensuring the sound level was consistent with what I had previously with the 1v output (when I had the volume on the preamp turned up higher). I went into the LMS settings and set the player volume gain to album gain and tried again. The results were reduced in detail then and smoother than I heard before. I think Chord’s fixed gain ratios of 1/3 and 2/3 give a better opportunity to preserve details than the variable digital attenuation of track gain or album gain. Plus, I suspect Rob Watts can expand 16 bit or 24 bit samples up to 32 bits before applying digital attenuation in the FPGA in order to preserve details. In LMS, volume gain takes in 16 bits and puts out 16 bits with attenuation and has a higher possibility of losing LSBs resulting in a loss of details. In quiet passages, digital attenuation could introduce quantisation errors but the designer should be able to avoid this in DSP.
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Doubt.
My long-time Chord dealer reached out and Chord told them it was fine. You keep using stock PSU’s if that is what makes you comfortable. Others are not required to.
Indeed, I remember advising this many years ago with the arrival of the original Hugo. The ‘turquoise’ level setting appeared optimum for the 252 and 552 NACs.
However digital attenuation works here because of the bespoke design of the DSP in the FPGA and proprietary multi element pulse array digital to analogue converters in the Chord products.
Such methods are not going to be necessarily transparent when using off the shelf components however, hence why Naim with their products, don’t recommend digital attenuation for best performance.
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I started this thread and with subsequent replies I am learning a lot too!
With regard LMS - what is album gain? And I assume you use the LMS software volume control - does this only work from 16 bits without padding out to 24 or 32 bits as you elude? I just wondered because I like to use LMS now and then, and using the software volume control is convenient (I don’t have an r/c vol control on the amp). Perhaps there is a plug-in which offers a better quality software volume control in LMS?
Any other LMS tips to get the best out of it?
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Ok, but some, such as myself returned the Hugo mk1 for repair quite a while back. I needed to provide the PSU as well I seem to remember. At the time the fault did look power related on the DAC… it turned out to be the batteries which we all know now need replacing from time to time.
I did later use a different PSU, but I was aware if that PSU caused an over voltage or spike issue, unlikely as it would be, I would be responsible.
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Once purchased it’s your property to do with as you please. If you are comfortable with invalidating your warranty then I don’t see an issue.
As per forum rules, please don’t post links or make direct reference to discussion on other forums/social media please. Thank you.
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To clarify here. Chord Electronics stated in their email to me - as you can see above - that the use of any PSU other than the one they supply will invalidate the warranty. So either that is correct or they are lying/mistaken. It seems to me that, being as it is their product, they won’t be mistaken and they have no reason to lie about it.
Note that the use of any PSU other than the supplied one will invalidate the warranty. Not that the warranty will be invalidated if another PSU causes a fault. It doesn’t have to cause a fault - your warranty will be invalidated if you use one.
@cb01 - no need for doubt at all. Just drop Chord Electronics an email seeking clarification if you disbelieve what they have said in their email to me. Personally I would rather trust in what the manufacturer says about warranty terms and conditions than what my dealer tells me.
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I have the LMS software volume control set to fixed at 100% (best) to avoid another step of digital gain attenuation. The “album gain” is one of a choice of “volume gain” settings in the LMS player settings window. The other choices are “none” (best) - no digital attenuation, “track gain” and “smart gain” - “smart gain” is one of track or album gain for playlist replay to even out the listening level. I think digital attenuation can cause a small loss of musical details in LMS.
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I don’t disagree. If one used out of spec RCA interconnects that somehow caused damaged, one would certainly be liable for that damage as well. Same with faulty BNC’s or an improperly terminated USB cable.
But, we’re contemplating a device that literally runs on the official 5V USB power standard. Unless the Qutest is particularly sensitive to power quality (per RW, it’s absolutely not), it seems more likely that a subset of aftermarket power supplies are not USB-compliant.
Not to call out one type of “booster”, but it was an entire volt high when I used that type on my Lumin D2.
My 5V/2A Plixir Elite BDC, however, is 5.04v at 50ma and 5.01v at the full 2000ma. Tightly regulated in a way that very few PS’s are. Only RME’s 12V SMPS has come close to that, from what has come across my bench.
So, a device is either USB-Compliant for 5V power (5v, +/- .25v IIRC) or it is not. The Qutest certainly seems to be. I am thinking that a bit of Caveat Emptor applies to one’s 3rd party power supplies. Sean Jacobs, James Soh, John Swenson are trusted engineers and all will furnish a lab report for your unit if asked. I know James sent me his printout for my 5V/2A and 12V/2A Plixirs.
That is a fair point. If the device is stated as USB powered, then it shoukd be powered by any USB source.
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I hve a great deal of respect for the Plixirs having obtained superb results when using one to power my former Melco N100 in place of the supplied SMPS. Having now upgraded to a Melco N50-S38, which has an internal P/S so just an IEC mains inlet, I now use my Plixir on my Melco D100 ripper. Incidentally the Plixirs are officially endorsed by Melco for use with their products so no invalidation of warranty.
There are many considerations when deciding on s suitable P/S. It’s certainly not as simple as ensuring correct voltage and adequate current delivery, or indeed that all LPS’s are superior to all SMPS’s, which is what some would have you believe. My own limited experimentation elsewhere in my system certainly proved to me beyond any doubt that one cannot replace SMPS’s with LPS’s at random and expect good results. Unless a manufacturer, as in the case of Melco, officially endorse the use of a specific third party P/S then I’ll stick with the supplied one. I have neither the time, money or inclination to experiment further.
Chord Electronics strongly advise against the use of a LPS with the Qutest on sound quality grounds in their email to me. Specifically they mention that LPS’s do not contain adequate filtering to remove RF. As stated before, they also say that using anything other than the supplied PSU will invalidate the warranty and whatever one chooses to do on sound quality grounds clearly the warranty issue remains.
Incidentally I was discussing with The Chord Company the possible use of a LPS with their EE8 switch in place of the supplied SMPS. They said that they had experimented with various LPS’s on the EE8 and other pieces of kit in their dem room but that they hadn’t found anything to really shout about.
This whole idea that seems to have grown up over the past few years of ‘all SMPS’s are bad news and they should be replaced with LPS’s’ is clearly at best very misleading and ill-informed and at worst just nonsense.
This sort of thing is not uncommon in hi-fi over the years. It’s so easy for what is actually nothing but just an opinion or belief held by some to be bandied around for years and for it to imperceptibly make the leap into being treated as undisputed fact by many people. This is actually a fascinating phenomenon in itself and of course not just confined to hi-fi.
So don’t just blindly follow the herd. Think, research and evaluate for yourself.
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Careful… some third party PSUs don’t incorporate the right HF decoupling for the powered device. This is is equally valid for SMPS and LPS. This is nothing to do with whether the PSU is switched or not. So unless the powered device is designed to be universally powered, in which case will contain additional power management, decoupling and safety circuitry in the device itself if it is sensitive to it, one really should use a PSU designed for that device. Otherwise one could drive the device out of specification including increased RF noise and additional EMF around the DC power lead. I suggest this is particularly pertinent for powered devices with digital electronics and clocks.
I have been pointing this out on the forum for many years now.
If in doubt use an RF EMF strength meter. You might be fine… but then again…
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This seems to be an eminently sensible, logical and informed approach that also seems to be totally disregarded by the hi-fi community at large, including reviewers. Most of whom lack the technical knowledge to make a properly informed decision. Ignorance is bliss here. Third party PSU’s, particularly substituting SMPS’s for LPS’s, which is currently very fashionable, are deployed with abandon in the misguided belief that they will always yield improvements and will not cause problems.
I lack Simon’s technical knowledge here - and am happy to be guided by him as someone who clearly knows his stuff - and my own admittedly limited experience bears out his assertions absolutely. My approach is now to stick with the supplied PSU unless another PSU is approved for use by the manufacturer - not by some magazine reviewer who has taken a fancy to it. The whole thing is a minefield that one ignores at one’s peril.
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Well said 
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For every sub-par LPS, I could point to a dozen SMPS’s that are simply wretched.
I have and use both types. But only quality units from quality manufacturers.
We are discarding the baby with the bathwater by making categorical statements. Real life isn’t that neat and tidy.
Neither is audio, wherein one could gain favorable improvements from a high-quality, well designed LPS in one system and clearly harm SQ by using that same LPS in another system.
There’s no homogeneity here.
NOTE: I apologize for disappearing from the conversation. I’ve been without electricity since monday morning at 0645 CST due to the hurricane, and resulting power outages, in South Texas. Power came back on an hour ago.
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It would be interesting to see in the hifi world those wretched SMPS you refer to (as opposed to low cost wall wart generic PSUs). In the delicate sensitive RF world I also inhabit (in addition to hide) I have some extremely low noise SMPS - sure these aren’t your common or garden power supplies but they provide the ultra low noise I need in those environments. One of them also has a switching frequency adjuster to adjust if the very sensitive powered equipment picks up on EMF from the switching power supply causing intermods that are getting in the way… It is all very precise and clinical… which a linear power supply isn’t unfortunately, the harmonics from a transformer saturating can be quite hard to control… however in audio and hifi we don’t need to be so precise so most power linear supplies will be fine and its often more about providing a very low impedance power source. They also tend to get contrasted with low cost or basic switching power supplies with poor or mediocre EMF management… here a mediocre LPS is likely to cause less interference.
But I think the point we evolved to is that the LPS or SMPS is largely irrelevant if both are quality designs - the key bit is the decoupling and regulation on the DC side to match the noise from the powered device. If the power supply is not specifically designed to power a specific powered device - it could be putting the PD out of its EMF compliance - by not correctly suppressing the EMF on the DC lead… this is more likely with power devices with high frequency clocks and digital logic circuitry… unless of course the powered device is design to be universally powered.
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This is surely of vital importance, especially when considering power supplies for network components such as hubs and switches and also DACs. It is something that appears to be pretty much universally overlooked. Of course hi-fi PS manufacturers have jumped on the bandwagon of current fashion and the last thing they want is for you to think that their shiny new PS could possibly put your device out of spec. So it’s all jolly good and nothing to worry about. Except it isn’t.
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