Chord DACs are all FPGA based DACS designed by Rob Watts who started out as a design engineer for Zetex semi conductors. Really nice guy did some work with him about 20 years ago. He also did the development of the Zetex Class D chip amp which sounded incredible back in the early 2000's when the only other alternatives were things like the ICE chip and the TRIPath

Alan Parsons quote - "Audiophiles don't use their equipment to listen to your music... Audiophiles use your music to listen to their equipment. "

DAC by Hugo, the new perfume for Audiophiles

Finally, after all these years, Dave apologises for his voice!

those battery terminals are awfully close to each other.

“You will hear the difference! Just don’t expect your friends to.” Omg lol you funny

0.0000000000000000001% THD, -10000000dB noise floor, $5 switchmode AC adaptor with 100mV of ripple

$4500 and they couldn't spare a few extra cents for a connector to make the battery removable.

I'm a bit surprised by how you soldered those connections. You decided to keep the leads long, but then did not take advantage of that. It would be so much easier to solder the leads with the batteries out of the case, taking advantage of the long leads by holding them with your fingers. It would avoid the insulation damage and also make it easier to do a good soldering job (because there is no tension on the leads that you have to counteract all the time). After finishing the soldering and testing, you can flip the batteries into place, possible because the leads are longer.

Audiophile forums are fun. I have found people hearing all kind of improvements after wrapping the power cord of their devices in aluminium foil, sound from speakers going out of phase when using different length of speaker cables in a setup ... etc

Made in England... $4500 $300 for the compnents and case. $4200 to figure out how to make it not leak oil...

That bluetooth module is the weakest link in that audio foolery chain. Its a $10 US part on mouser. Neighbour likely just paid more than that for the two replacement batteries. Not impresed.

The weird battery behavior could be a rebalancing circuitry going crazy when only one battery is connected.

Found one used £399 boxed with charger……that’s more like it! But can you imagine what the audiophiles are paying for headphones to plug into these puppies!

DankPods had a Chord Mojo. I think his also broke. Was thinking a repair/teardown collab sort of thing with EEVblog would be really interesting.

At the mentioning of the 0-8-15 BT module I spilled my coffee 😀

Audiophiles! Do they really think the recording studios use $10 000 A/D/A converters and $1 000 microphone cables? Newsflash! If you think they make a difference, the music you are listening to is already ruined in the location is was recorded.

I was always impressed by the audiophile speaker cables made with unicorn bone and human skin that cost $100 a foot. Macintosh owners usually fall for that stuff.

"Don't just cut the cables like that..." "..that would be rather unpleasant." I learned that the hard way when I THOUGHT I had disconnected power to the electrical cable I was cutting. ("Romex" or NM-B in the US) Ruined my cutters and burned my hand, but that wasn't as bad as the embarrassment.

It has an in-house FPGA as a DAC which is pretty esoteric as far as most Hi-Fi DACs go. And probably why it has a following, high price etc, as it likely has a unique sound signature.

I kinda love the audiophools, they put my tool and measurement equipment spending into perspective. :P

Feel better Dave!!

I still remember in the mid 90s some professor did a blind test in an auditorium with a load of audio experts and enthusiasts. the equipment that won overall was a cheap off the shelf amp with doorbell wire to connect the speakers :D

I am a recovered audiophile who then converted to "pro" (studio) gear as it is better value, fits my job and I prefer "flat" sound it turns out. Not sure what headphones you neighbour has but that is often where the real money is, the headphone amp is kind of just an accessory to that price wise. The price of amps is often just a 1:1 map to older headphone amps that were genuinely expensive to engineer before the "battery hack" lithium cells allow, FPGA and class D etc has largely made a headphone amp a "software" exercise, though the proprietary FPGA bitstream is still valuable I guess. What you are really paying for is the expensive staff of the manufacturer - the scale is tiny for audiophile, unlike "pro".

Who needs enemies when you have audiophools for neighbours and they rope you in to repairing their insane expensive stuff?

Can you test the capacity of the old batteries in case the high drain on the upper cell is the actual problem rather than the cell itself?

I just did almost the same thing for a neighbor. I did not realize how expensive they were. He also wanted me to add a super capacitor in parallel with each battery to do something to make the audio better. Evidently it was done by somebody on a forum. It was a bear getting those super capacitors in there. I also found that there is a difference between a ‘protected’ lithium battery and ‘non-protected’ batteries. These units need ‘protected’ lithium batteries. Also, as you saw, on that one battery, the pos and neg are stupid close to each other. (I did short it out accidentally but just a small spark). I used Orbtronics protected batteries.

You should have used audio grade batteries. They are made with a wooden case around them to reduce resonances as the lithium floats around the cell.

Love how KZfaq subtitle makes it audio file. „Files off all the sharp digital edges of“. I remember reading something along the lines of „the noble 32 bit high end chip“ in a audio magazine and it was just a normal ARM7 micro.

I'm wondering if on the other side there might just be some somewhat larger electrolytic capacitors as filter capacitors in the power chain, which, would potentially register as a short when they're not charged? I think that might explain the sort of behavior you are seeing. If the thing was getting external power when you put the batteries in, or, just had been charged recently enough, then the protection circuits on the batteries might not trigger, but, with the caps empty, maybe they would, and sort of get stuck that way until it's put back in without that problem? I could definitely imagine a scenario like that. It's kind of too bad that we couldn't see the other side of the board. I was really surprised with all the weird stuff that came up in the process that you didn't at least look at the circuit there, though, I do sort of understand why it would be potentially risky to unscrew things.

$4500 and the plastic case looks like a $5 thing. But since I have seen "actively shielded" audio cables with batteries and blue LEDs ($200 each) I believe everything... Or a $1000 power cable.

i'm an audiofool. i have the mojo 2. i can hear the difference. i swear. 😀 - also the clicky noise is a relay. the mojo at least has a relay that connects the dac to the amplifier after some kind of internal self test. the mojo 2 has a bunch of blikenlites that show you some kind of debuggery of a self test.

yes if the cells are in series you need to disconnect the high side cell 1st and reconnect high side last otherwise the bms may crowbar due to the loss of ground reference (depends on topology but just to be safe) and never disconnect/reconnect fully charged cells 4v is nearly fully charged (4.1-4.2v)

I like this new Dave’s voice module better than the legacy one! 😅 Get well soon!

I was just looking at a "valve" preamp box, with, of course, separate power supply box, with full bridge tube rectifier, Hand wound transformers... starting price: €22,000

I've got their Mojo and Poly unit, it's for running some big old headphones that my amplifier will barely touch, some classic jobs from the 70's that look far nicer than they sound! :) But oh boy when I run my in ear monitor speaker things with it, it's sounds *beautiful*, but it's a tad impractical for that kinda use

Audio Science Review tests dacs, surprise surprise, the very best performing ones don't cost the earth.

Nice video, thank you :)

I would not have touched this. $4500 sucker price. One wrong slip of the soldering iron and your neighbour would be expecting you to replace it. No matter what. He was probably quoted $4000 to replace the batteries by OEM.

But, made in ENGLAND!! For that money i would have expected it to be made in Japan at least.

I love Audiophool videos. The audio cable fanboys are the best. I once watched a video of someone gushing about how audiophile cables improved the sound quality in their system, so being an electronics geek, I thought I'd test one of my RCA / Phono cables that I have on my bench, and respectfully post a comment on the video: '' I've just tested a standard, cheap, homemade RCA cable on my lab bench using a Hewlett Packard 3314A Function Generator, a Keysight U3402A Digital Multimeter and a Siglent SDS 1104X Digital Storage Oscilloscope. The negative 3dB points ranged from below 20Hz to several Megahertz, and the resistance of both conductors in the cable was around 0.1 Ohms. The sinewave didn't change at all until the negative 3dB points were getting close'' I think he said that he can hear a difference between cables. 🤔

Could it be that you need to put it in some power off state before servicing it? Like holding the power button in for 10 seconds to completely powering it down and not just soft-switching it of?

Dave! howcome using the wirecutters to cut both strands of battery wire can short the battery, but when installed in the misbehaving circuit board suddenly the built in cell protection circuit can prevent shorting the battery.?

When it comes to audio gear I find that audio quality vs price is very much like an exponential curve. A device such as a DAC the sweet spot for "value" would probably be around the $200-$400 mark. This will get you 80% or so of the audio quality. Spend any more than that and you are only gaining single-digit increases in quality but spending exponentially more. That "Hugo" DAC is probably around the 90% mark for the price-point. You could spend tens of thousands of dollars on a DAC and only gain another 5% of quality over that. I have a good friend who had spent over $150,000 on a home HI-FI.. mine on the other hand? $300 speakers (which I had to repair, that's why I got them cheap.. they are probably worth $1000) and an amplifier made in 1983 by NAD which I got for the cost of a carton of beer (a common currency here in Australia). My stereo really does sound fantastic for the money.. my friends' stereo absolutely sounds better.. but $149,650 better? NO WAY!! Mine sounds 80% as good as his.

Chord uses a FPGA DAC. I had to look up what that meant and found this: "FPGA-based DACs use a combination of digital signal processing and analog circuitry to convert digital signals into analog signals. FPGAs are essentially reprogrammable logic chips that can be configured to perform a wide range of digital signal processing tasks."

Chord use a proprietary FPGA based DAC based on 'taps'. It might also have an active cell balancing circuit.

Being the dual rails, if the insulation on the batteries was compromised, it would short the one battery. Negatives shorted together, the one positive would be shorted to the negative. Hope I didn't make it confusing. Doubt that both batteries insulation was damaged.

At least the thing makes sense from a electronics point of view. Using batteries and linear regulators as a low noise power supply is actually kinda smart for audiophiles. I would have expected them to go all out on the soundwood and directional cables in this :D

Yes... $4500? I would imagine a top-quality very ruggedly built one to cost maybe $500. (Think of professional gear for recording studios or traveling musicians.) There's high-end and then there's H$GH-end!

I reckon it has some sort of balancing circuitry (the old batteries were pretty much identical voltage) and that was going a bit bananas when just one battery was connected

Hey Dave. Is it possible that the protection circuit in cells doesn"t play nice with protection circuit of the device self? for sure there is a charging ic on there. sometimes that gives some weird fault if there is a second protection between it and the cells. Maybe?

The multi-cell battery may be balanced using a management system. A quadcopter drone battery pack has a read-out that shows the individual cell voltage as a health check.

Worst audiophoolery I ever had to do was upgrade a power supply on a media streaming box from a DC plug pack to a very* expensive custom specially designed linear power supply. Best part is the streamer connected over wifi and output a digital audio signal (via optical I think). From my experience the people who go really wank with their multi thousand dollar cables plugged into bog standard wall outlets with no other filtering are just spending money because they have it and that’s how they find new people to talk to.

after paying full price for a Dragonfly Red, I soon realised that it truly is audio-foolery !

what dvm and psu setup are you using? i love the onscreen display and control.

All these opinions about audio quality makes me want to listen to my music collection on C-90 cassettes from the 80's. Unfortunately my mint Sony TC-KB920S has a mechanical problem...

Personally I got a Vantec NBA-200U for $20 brand new. The only issue I have with it is a DC offset issue. Honestly it sounds really good for the price. There's no way I'd pay what that that Hugo thing costs.

It has a very 2000s tech look to it and not in the "OH COOL RETRO" way, like the, "OH that's why we don't make things look like that, anymore."

I can blame, taking things apart, for the knowledge I've acquired. Just finished my BIG LED project. 2'*2' addressable 5050 RGB. Just have to fabricate 4 aluminum solder paws for the footprints. 😂😆

😂 I like your voice. And the electrons don’t fall out when you put it upside down if it’s make in the old da😂

is the battery problem active cell balancing? pulling one cell down to match the other.

Man the genious placing of those pads on the board... Could have been ever closer too eachother -.-

I've seen and listened to some BS setups - guy at work had spent literally TENS of thousands of pounds (UK) on Cyrus CD player, pre and mono block amps, Chord DAC costing over 10k and something like a grand on two RCA cables. The speaker cables were as thick as my thumb and were raised above the floor on special 'ceramic things' whatever that cost I have no idea. All of this hooked up to some boomy/flappy sounding 1970's floorstanders - it sounded absolutely bloody awful!

I bet its an anti-repair feature they added to make you send it to them to have the batteries replaced. Then they charge you extra for attempting to change the batteries yourself.

I hope you get better soon. Very weird "fault" indeed. I wonder if there's a battery balancing circuit at play, but it certainly shouldn't create a dead short across the cell. You might look into some non-serrated wide-jaw pliers for handling wire with low temp insulation (knipex 35-12-115 for example).

How many EEs does it take to change two batteries? ....... 😅

oooo! they even sealed it with eight screws to keep special audiophiliac air inside. but it's gone forever now.

Probably linked with the fact that those cells ain't in paralelle but provide 2 different rails, if minus voltage is there first maybe it cause a problem, something like that.

Let me know when I can pre order my EEVblog "one helluva 400 dollar dac"

These days you have to work quite hard to find a DAC that is subjectively "bad". A few years ago, things were rather different. The temporal resolution of human hearing has been estimated as on the order of microseconds, and this is related to the need to determine the direction of sound sources in nature, so clocking may actually be a factor.

The reason they put battery power into those things is to eliminate noise from the switching power supply. So it is surprising to hear the inductor whine from it.

When you start to have money to buy those you have already started to lose your hearing. so you may miss added increased quality from those products. Maybe same that I would liked to have my Genelec speakers like 10y earlier when I got those. I have already started to lose hearing range from hi freq.

It's a fake! There isn't a single ECC83 to be found 🤣🤣🤣

I think the BMS was going a bit crazy while trying to cope with the imbalance during battery change

Dicky batters, I had the batteries in a pair of headphones get iffy (you could only charge them if they were turned on first). New batteries TFW!

My guess is that the switch was ON when you soldered the first battery. At that point any OP AMP would work with improper bias and the output stage could drain quite some current triggering some protection at that point. From an engineering perspective IMHO only a fool would make the dual rail voltages that way though...

I would not be surprised if there is a BMS in the device itself fighting the BMS in the batteries you put in. Did you peel the old ones open to see what (if any) BMS stuff is inside? If this is the case, you connect just one cell, the BMS in the device will detect a much higher voltage on one of the batteries and will try to discharge that to equalize the voltage with the other (disconnected) battery.

Maybe if the battery protection circuit gets activated, it presents a short at the terminals. The short might not be in the DAC itself.

Had a laugh too with the record player. All that expensive stuff with a medium that has a lower bandwidth than a CD.

This is a Triller episode!

Im watching this with smartphone DAC connected to a laptop (on Linux it works out of the box). Because internal has different levels between channels (almost sent back my 170 $ headphones) and its not easy to remove main board (old Thinkpad). And this external sometimes makes little silent but audible siren in one channel... I always had bad lack with DAC-s - not only audio :/

Regarding the battery situation, maybe there is a balancing circuitry (to ensure equal + and - voltages), which initially connected two batteries in parallel - causing current spike, that tripped the second battery protection, which confused that balancer, causing it to basically short the second battery. Just a theory.

1) NUTS to have the power pads so close to each other!, 2) That price is WAY WAY BEYOND INSANE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Selling $200 device with a $4300 markup. Should we clean all the THT flux off? Nah, that would cost too much.

One would think for $4500 they could engineer a lesser-buzzing power section. I guess the cost all goes into superconducting PCB traces. 😅

$4500 of inductive hum. Just what the audiophool will NOT hear. LOL!!! You should charge $500 for the battery change👍👍 A bargain at twice the price!!

I tried to register at the eevblog forum but every time I try it says "bots are not allowed to register". Any ideas anyone? I'm not a bot, honest. I've tried a couple of different browsers. There's a dropdown field "are you a bot" which I've answered both yes and no to no avail. :)

Those battery pads are too close for comfort.

18:00 some type of automatic battery equalization?

I would be worried the weird behavior was a fault that made the old batteries discharge quickly and seem bad.

totally OTT and often dont even measure that well, but yes, they roll their own dac in FPGA

i have a sound sensitivity issue, and for better or for worse i find a good sound experience for me has a euphoric note to it, so there's the drug addict motivation i guess. what will improve the sound?!?!? ILL BUY IT!!! . there is a sound difference, a human brain can detect 100ns differences at -300db or something obnoxious like that. whether everyone appreciates it or not enough to pay the money is the catch.

nice to see 4,500 doesnt pay for a flux wash!!

Interaction between the cells? What will they think of next, Dave?

Looking at the Audio Science Review website, the Hugo 2's performance is good, but can be beaten by much cheaper DACs.

I would have feared of damaging it, when disconnecting the bats one at a time. Dunno what happens when there is only one rail.

You're the best man going. I want you knighted for services to the English language

Why do they print the circuit board with the battery solder pads so close to each other? Seems avoidable.

Seems like the unit is synchronising the battery voltages so the positive and negative voltages are as close to each other as possible.

Buy something value for money like the Ultimate Preamp 2. Made in Australia by Australians.