Thread: Chord QBD76 upgrade to async 24/192

I primarily listen to 44/16 content on my QBD76 via stock USB. I've been debating whether to build a CAPS server + Lynx AES16 or get Halide Bridge/WaveLink for the QBD76 just to get async USB. Do you think the async 24/192 upgrade for QBD76 is worth it for 44/16 content? Is it much of an improvement from the old 44/16 adaptive USB?

I think its safe to assume that the buffer would mean the same end result, namely vanishingly low levels of jitter.

Ron

How much does the upgrade cost? Just curious.

"I find the Chord QBD76 to be relatively sensitive to the PC and usb cable"

Quest, have you tried the optical/toslink connection? My perception of the QBD76 is that with the buffer one does not need to worry about the jitter associated with toslink yet you get the benefits of complete isolation from the PC, and no RFI/EMI "creeping in" via the cable.

As an aside, I have read reports (I believe Eloise has mentioned it too) of 192/24 achieved over the toslink connection in some setups (dependent on the soundcard I would imagine).

Ron

Thanks for the update.
I'm looking forward to your review of the async upgrade vs other options.

"Btw what's odd is even when using optical, you can still hear the difference if, for example, you change the PC's power cord. So galvanic isolation is not everything..."

Quest, I would contend that it is everything, and that your finding only underscores this. While optical takes care of one connection between PC and DAC, the other connection, namely the mains, needs to be also addressed.

Are you using any mains filtering devices in your system?

Ron

Quest, thank you for sharing. I was certain a PurePower regenerator and connecting to the DAC via toslink would completely isolate a noisy PC from the DAC and rest of system. But you say the power cord of the PC still makes a difference. Not what I want to hear but I accept your experience as being more valuable than my hunches and assumptions.

Ron

Hi Quest (and everyone else),

I'm a QBD76 owner as well. I upgraded from a Naim DAC last year. Probably unusually though I currently use a Linn DS as the transport, so effectively ethernet/SPDIF conversion with remote via iPod touch.

I'm interested whether this can be bettered as a transport so this site and particularly this thread have caught my eye. I've plugged a laptop straight into my DAC via a Starlight USB cable (bypassing the mixer stuff) using Foobar and this is around on par with the Linn DS. I also have a Musical Fidelity V-Link that I'm experimenting with, but only minor differences really and not enough to lose the convenience of the Linn DS control. I'm not entirely convinced it's any better than direct USB connection either.

The availability of the QBD76HD upgrade has complicated things now as I was going to try building a silent PC with a soundcard such as RME 9632 or AES32 and try it out. If this didn't better my Linn DS then I could use it for other things anyway (particularly the 9632 to rip my vinyl).

So many questions now though... Is the new HD upgrade for the Chord a better choice?? I was quoted £480 by Chord and £680 by a dealer so don't know which is the right price! I'd love to know if this would sound better than the silent PC optionwith soundcard or even if the HD upgraded DAC would further benefit from it anyway even via USB, working on the "everything counts" approach?

Looking forward to your further summary of the upgrade.

Thanks for all the really useful information.

Your initial feelings about the upgrade are very interesting. I've found when experimenting with sources/cables there's often a trade-off between dynamics and smoothness (apart from with the Starlight USB cable which was better all round) so this is good news.

With regard to the Linn DS, I bought it as a complete solution so was originally using it's in-built DAC. When a dealer attached a Naim DAC via SPDIF it was obvious the DAC part of the Linn could be improved, but actually it sounded best of all via a directly attacheched USB stick. This is what made me think the Linn could be bettered as a transport. I guess in reality that Linn has no real incentive to provide an outstanding SPDIF output considering they have no stand alone DAC of their own. This is a shame as the thing I'll miss about the Linn setup is the ease of use and convenience of full control via iPod touch.

In conclusion, I'm still keen on building a good silent PC, but am going off the idea of the soundcard route based on your comments and others I've read. USB seems the way to go now for quality/convenience. I'll be really surprised if even second generation converters can beat the direct asyc input into the Chord if they've implemented it well, but I look forward to your comparisons...

Either way I think I'm going for the HD upgrade. Can you let me know how much you paid and where you had it done (by PM if necessary)? I've had conflicting pricing.

Good to hear that I wouldn't be losing too much convenience. Since moving to digital sources I've listened to far more music simply because it's accessible. Just out of curiousity, what is the iPad/iPhone solution you use?

I wouldn't know where to start with modifying the DS! I'm quite attached to it though so will probably move it to another room for less than critical listening.

I phoned my dealer today and asked them to verify the price so I'm hoping it will come down. They actually send the unit back to Chord rather than carry out the modification themselves. Interestingly, they said that Chord had taken the opportunity to make general improvements to the DAC for the HD model/upgrade. I have no other verification of this, but it does bear out what you're finding sound quality wise that it's possibly not just asyc USB and higher sample rate addition in isolation but a general upgrade too.. Chord are apparently very happy with it!

I'll let you know how I get on over the coming weeks.

Gentlemen,

I sold off my QBD76 and upgraded to a Jet Black QBD76HD. When I received the unit I tried it with the HD cable and it sounded quite bad with this input. I was not sure what to attribute this to. I was using an Audioquest Diamond USB Cable on the standard input and this set up was much preferred. The soundstage was sucked away when using the HD input, so I stuck with standard.

I do have a somewhat close affiliation with Chord so I contacted them. I explained that with Amarra 2.3 the HD input was not sounding very good at all, actually being unlistenable—making me wonder why I even upgraded to the HD unit!? They did some checking and also contacted Amarra. Weeks later they offered me a modified chip upgrade for my QBD76HD which I was sent. It took me some time to organize having the chip installed but when I did have this done I was absolutely astounded by how the proprietary HD cable that ships with the QBD and the all of my standard res files were superior to that of the standard USB input. I have since stopped using my very expensive Diamond Audioquest USB Cable. If anyone is interested I would sell this at a low cost, it is I think about 10ft long and I have the original packaging, it is only six months old. The cable is fantastic but since Audioquest can not make me a custom USB cable to work with the QBD76HD I don't see the point of using it as I can not go back.

I am however looking for a company, possibly Chord Cables or Transparent to produce a custom cable for me for the QBD76HD so I can see what the differences may be. Chord Electronics has assured me that they feel the cable that ships with the unit is as good or better than any other on the market.

The sound :

Mathematically there is little rationale for the HD input to sound better with standard res files as in essence all of the inputs are jitter free when the full buffer is enabled. Although I was told that in theory it's a faster clock on the HD input and thus should result in better sound. Well, it is much more than better. The sound became wholly more spatial, radically warmer and more transparent and less edgy at the top. I would never have suggested before that the sound of the QBD 76 had been edgy until I heard the difference as it was an instant and unforgettable observation.

I highly recommend getting the upgraded chip for the HD unit. I would also suggest that depending on when you received your QBD76HD that you check with your dealer on a possibly chip upgrade. I had my chip sent to me in September 2011 and did not install it until early December. Should you need any help in determining more details on what the chip is called I can try and ask for the exact details on this chip upgrade so it is easier to get information on from your dealer.

Best wishes,

Derek

P.S. I also have information on the spec and availability of the new HD circular USB connector should anyone have need of this.

I'm very interested in details of this chip upgrade.

I had my QBD76 upgraded to HD in September. The first completed upgrade developed a fault with the clock, so I'm wondering if when I sent it back in late September I got the different chip back or not. The reason I wonder is as follows:

I have a CAPS server with the SOTM USB card. It's by far the best transport I've tried yet. Since it has two outputs I did some testing last night between the adaptive (USB1) and assync HD (USB2) inputs on the Chord. I was surprised to find that they were very close and if anything the old input sounds more balanced, smoother and with more body to the vocals in comparison, without losing any resolution or dynamics. The HD input should easily best the standard USB input in my view, so I'm not feeling I've got the best from the uprade either.

I'm using a fairly inexpensive Wireworld USB cable on the standard input.

Chord's support are fabulous, but I'd appreciate your thoughts before I approach them.

Regards

Mark

Mark suggested... "The HD input should easily best the standard USB input in my view".

Surely Chord's buffer is designed to reduce dependence on transports and therefore should reduce the difference between adaptive and asynchronous USB interfaces. There *may* also be better isolation with the slower speed USB. I'm more surprised by comments that there's a big difference than by comments that the differences are marginal.

Yes, you'd be forgiven for thinking the buffer is a great leveller of transports, but the Chord is still surpringly sensitive to differing transports and even inputs. Some other owners also bear this out.

For example, my Linn DS feeding coax sounded inferior to my CAPS through a v-Link. Way too soft and muffled! Also, if I feed either of the Chord's USB inputs from the CAPS standard USB output port and compare against the SOTM USB output port there's again a significant difference.

Interesting stuff and food for thought. I'm hoping to hear from the other Chord owners on here for their thoughts on both this and the difference between HD Async and Adaptive USB on the Chord DAC.

Hi Guys - I have my full review of the Chord QBD76HD ready to publish. I'm waiting on one small detail from the distributor. It should be on the front page later this afternoon.

Hi Chris,

I'm pleasantly surprised that you've got round to reviewing the Chord and enjoyed your write up today. Your perspective is very different to what I've read previously in mainstream publiction. Also, I've never heard the DCS Debussy or Alpha DAC so those comparisons were interesting.

I bought my Chord a few years back after not getting on with the Naim DAC. I've always loved the 76 but the HD upgrade took it into another league - especially with the CAPS 2. This combination is the first digital setup I've heard that finally bests my vinyl setup in every area whilst still retaining that beguilling analogue quality that draws you into long listening sessions...

I'm interested in the DSD chip and whether that's a general upgrade in sound quality or simply facilitates the conversion? I didn't know if was available at all.