Feb 1, 2017 at 3:44 AM Post #7,411 of 27,088
I no means disrespect Rob design philosophy. In fact, like many of us, we still think Rob gave us the best DAC money can buy for many of us. And I still stand by my option, Rob knows what he is doing to gives the best sound down to silicon level.
 
Please go back a year ago, understand why Dave success, other than the 160k+ tab, it is the USB input that set Dave apart from other DAC in the market.
 
As with Dave, when Rob mention Dave sound exactly the same regardless what usb cable or upper chain source used. We all heard it, it does makes a diff what source you use and what USB cable we place in between our source and DAVE, even with the almighty USB input on the DAVE. So every stange of isolation counts.
 
 
 
Quote:
   
I believe you missed what I said about Rob's reasoning on why he didn't include galvanic isolation at this input on Blu2.  It's probably a bit premature to be thinking we know more than Rob about where galvanic isolation should be placed on Blu2.

 
Feb 1, 2017 at 3:56 AM Post #7,412 of 27,088
As with Dave, when Rob mention Dave sound exactly the same regardless what usb cable or upper chain source used. We all heard it, it does makes a diff what source you use and what USB cable we place in between our source and DAVE, even with the almighty USB input on the DAVE. So every stange of isolation counts.

 
This is true but I am convinced these differences have less to do with DC isolation (which is what galvanic isolation accomplishes).  As you stated, even with DAVE's excellent galvanic isolation at its USB input, sources still can sound different and so why would adding the same galvanic isolation at Blu Mk2's USB input be any different?  I think that sources sounding different (better) has more to do with other issues like device impedance leading to better responsiveness.  If you look at the microRendu or sMS-200, they offer no galvanic isolation and yet they make a very significant difference.  The Uptone Audio LPS-1 is suppose to offer galvanic isolation against ground and against leakage current and yet my Paul Hynes SR7, which is connected to ground, sounds better than the LPS-1.  I believe one of the best 3rd party USB galvanic isolators you can buy is the Intona Industrial and having tried this with the DAVE, it resulted in no improvement.  In my own experience with the various isolation techniques I mentioned above, they made none to minimal difference and sometimes, they led to worse SQ.
 
Feb 1, 2017 at 4:11 AM Post #7,413 of 27,088
 
Edit: Yes I just checked the manual (http://www.chordelectronics.co.uk/wp-content/uploads/2016/09/Dave-User-Manual.pdf) page 2, and it definitely says 4x DX Digital Outputs. I don't see any DX Digital Inputs...

 
This is a typo and the manual has a few (including DAVE's output impedance).  My guess is that when DAVE was designed, the concept of an M-scaler possibly was not in Rob's consciousness whereas his digital amps were.
 
Feb 1, 2017 at 5:30 AM Post #7,414 of 27,088
John, here's an interesting ad by this broker on Audiogon here in the U.S. for Hugo2.  If you read through the ad, the potential buyer is made to believe Hugo2 is already shipping:
 
https://www.audiogon.com/listings/da-converters-chord-electronics-ltd-hugo-2-new-the-brand-new-dac-headphone-amp-from-chord-2017-01-29-digital-54351-marbache
 
What is interesting is they seem to have a good transaction rating with their customers but of the 12 positive feedback they have received in the past 12 months, 6 of them come from one customer who appears to be a friend of the merchant.  Red flags, for sure.

 


I assume that the photos are copyright as well...
 
Feb 1, 2017 at 5:46 AM Post #7,415 of 27,088
 
Rodney, I would say bypass the 3 series and go for the Compact Alnico Monitor which can be custom made by Louis Chochos to fit your desk.  It is a considerable upgrade to the Super 3 or 3i.  It can be driven directly by DAVE and the pairing is a match made in heaven although you will want to find a good fast subwoofer to add to the mix.
 
As for cables, you will want to get some adapter to allow you to directly connect a pair of RCA interconnects to a pair of speaker cables.  There are many who can make you such an adapter.  There are a wealth of great cables to choose from that will sound good but it shouldn't come as any surprise if I suggest that you audition the High Fidelity Cables.  In this application, they really really shine (even their entry-level Reveal line) and HFC can also make you the adapters that you need.  Everything can be auditioned with a money back guarantee.

 


Just a question, if the speakers can be custom made why bother with speaker terminals at all, why not run direct from speaker terminals to an RCA connector using one's favourite speaker cable?

Convenience will take a knock and it certainly wouldn't degrade the sound but would be as pure a connection as can be - unless the Dave end is soldered to Dave's board :-)
 
Feb 1, 2017 at 6:41 AM Post #7,416 of 27,088
I am not sure about sms-200, the urendu does have galvanic isolation. but at the network input point.
 
 
 
Quote:
   
This is true but I am convinced these differences have less to do with DC isolation (which is what galvanic isolation accomplishes).  As you stated, even with DAVE's excellent galvanic isolation at its USB input, sources still can sound different and so why would adding the same galvanic isolation at Blu Mk2's USB input be any different?  I think that sources sounding different (better) has more to do with other issues like device impedance leading to better responsiveness.  If you look at the microRendu or sMS-200, they offer no galvanic isolation and yet they make a very significant difference.  The Uptone Audio LPS-1 is suppose to offer galvanic isolation against ground and against leakage current and yet my Paul Hynes SR7, which is connected to ground, sounds better than the LPS-1.  I believe one of the best 3rd party USB galvanic isolators you can buy is the Intona Industrial and having tried this with the DAVE, it resulted in no improvement.  In my own experience with the various isolation techniques I mentioned above, they made none to minimal difference and sometimes, they led to worse SQ.

 
Feb 1, 2017 at 7:20 AM Post #7,417 of 27,088
This is a typo and the manual has a few (including DAVE's output impedance).  My guess is that when DAVE was designed, the concept of an M-scaler possibly was not in Rob's consciousness whereas his digital amps were.


Actually Romaz, if you look at your own photo of the Blu 2 and DAVE connection, it seems that Blu 2 is connected to DAVE via BNC3 (& presumably BNC4 for 1 million taps) input. I believe the DX inputs is just using two BNC inputs. The DX outputs are still the DX outputs. I think Chord has always designed their DACs this way (as this was the case with my old QBD76 too) where you can use two adjacent BNC inputs as DX inputs.
 
Feb 1, 2017 at 9:16 AM Post #7,418 of 27,088
Just to clarify - the M scaler connects to the dual BNC inputs (BNC 1 and 2 or BNC 3 and 4). The DX outputs are always dual BNC 705/768 kHz, SPDIF but with one important difference - the volume control data is in the user data of the SPDIF, together with a preamble in the user data identifying the data as DX. 
 
Rob
 
Feb 1, 2017 at 11:56 AM Post #7,421 of 27,088
Actually Romaz, if you look at your own photo of the Blu 2 and DAVE connection, it seems that Blu 2 is connected to DAVE via BNC3 (& presumably BNC4 for 1 million taps) input. I believe the DX inputs is just using two BNC inputs. The DX outputs are still the DX outputs. I think Chord has always designed their DACs this way (as this was the case with my old QBD76 too) where you can use two adjacent BNC inputs as DX inputs.

 
  Just to clarify - the M scaler connects to the dual BNC inputs (BNC 1 and 2 or BNC 3 and 4). The DX outputs are always dual BNC 705/768 kHz, SPDIF but with one important difference - the volume control data is in the user data of the SPDIF, together with a preamble in the user data identifying the data as DX. 
 
Rob

 
Thanks for clarifying.  It appears I have misunderstood this!  The thought then crossed my mind that another DAC with dual SPDIF inputs could potentially tap into M-scaler's full potential but then for this to work, they would have to be usable simultaneously and in aggregate and I know of no DAC that has this capability.
 
Feb 1, 2017 at 11:58 AM Post #7,422 of 27,088
I am not sure about sms-200, the urendu does have galvanic isolation. but at the network input point.

 
Yes, the microRendu is galvanically isolated at its ethernet input and so is the sMS-200 but this also applies to my Mac Mini, Intel NUC, Mac Pro, my laptops and all things that have a hardwired network connection.  As far as I know, John Swenson didn't go to any extraordinary lengths to incorporate an special galvanic isolation in the microRendu beyond what the ethernet protocol calls for which is why he also added "ethernet filtering" but this is nothing unique as even my Mac Mini offers this.
 
I am not a networking expert but it has been my understanding that the ethernet protocol has called for transformer coupling dating back to 10base-T and so by definition, all modern ethernet connections are galvanically isolated (usually to several hundred volts) and so this is a key advantage that audio over ethernet has over other transmission protocols.  This transformer-coupling spec was introduced not for the benefit of audio but because ethernet can support fairly long runs such that equipment on different ends can be powered by different power distribution networks within a building or even different buildings which could then lead to a significant ground offset between ethernet nodes.  As we know, however, this transformer coupling does nothing for RF created by the device itself which can be significant and why DAVE's galvanic isolation at the USB input is still very important.
 
As we also both know, a microRendu is superior to a basic PC even though both have galvanic isolation at the ethernet input and despite DAVE's galvanic isolation at USB and so this is what I meant about the differences being due to more than just galvanic isolation.  There are many on other threads and other forums who talk of even more robust network galvanic isolation devices (to the degree of many kV of isolation) leading to even more SQ improvements.  These devices would include the GISO by Acousense, the Acoustic Revive RL-1 or the SOtM iSO-CAT6 and I happen to own the SOtM iSO-CAT6.  When used with my other DACs including a Oppo BDP-105, there is a small but noticeable improvement, worthwhile enough that I bought it last year.  When used with my DAVE, it offers no perceptible improvement and I have documented this several times in the past.
 
I guess what you are trying to say is that it doesn't hurt to have multiple points of galvanic isolation but does it make a difference?  Rob suggests that it won't with his design and my experience tends to support his claim but I suppose we will be able to answer that question for ourselves with the Blu Mk2 soon enough.
 
Feb 1, 2017 at 12:58 PM Post #7,424 of 27,088
Okay with a single BNC S/PDIF it’s possible to transfer 88.2 kHz, 176 kHz, and 352.8 kHz to any DAC. With a dual BNC S/PDIF it’s possible to transfer 176.4 kHz, 352.8 kHz, and 705.6 kHz to the DAVE. But how is the audio signal divided between the two BNC S/PDIF? Left – right, FR or some other way?

 
Feb 1, 2017 at 1:09 PM Post #7,425 of 27,088
  Okay with a single BNC S/PDIF it’s possible to transfer 88.2 kHz, 176 kHz, and 352.8 kHz to any DAC. With a dual BNC S/PDIF it’s possible to transfer 176.4 kHz, 352.8 kHz, and 705.6 kHz to the DAVE. But how is the audio signal divided between the two BNC S/PDIF? Left – right, FR or some other way?

i'm not sure that's how it works. The Dave is still the DAC. There is no audio signal being passed, only digital data, between the Blu2 and the Dave.
 

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