[flyte3333]

Are you using that as an SRC (sample rate converter)? If so, I would probably advise away from that.

Agreed. While MacOS can sometimes convert sample rate, when using Roon or most other popular players , you can use Exclusive Mode (or ASIO on Windows) for bit perfect playback.

I don’t care about MacOS’s sample rate conversion when watching Netflix or YouTube etc. Music listening is a different story for me though - bit perfect playback all the way.

 

[fluidz]

Reflecting on my post earlier on..

I popped over to a local chord dealer today and listened to the Hugo 2 . A/B testing against a Mojo.
Listening to my Hd800S[s model] what I found was a pleasant surprise. The Hugo 2 does indeed widen the soundstage a little and give the low end a boost. I used the default settings, and didn't like the eq filters much.

Still a nice upgrade. Going back to the Mojo the HD800S sounded congested for a while until my brain adjusted :/

+1 For Hugo 2 it's pretty amazing but imo just a tad expensive given that down the road there may be battery issues.

I also tried the lcd3's out of my Mojo, and the Mojo drove them flawlessly. Mojo + Planar = great match. Just a shame the Hd800S requires that extra touch the Mojo can't supply adequately.

 

[Rob Watts]

Thank you for the well written answer.

1. So the Hugo 2 has 2.75 dB overload margin. The reason I asked was because Benchmark Media state their DACs have around 3.01 to 3.5dB of headroom. Which do you think is the optimal amount and does Hugo 2's "headroom" increase as you lower the digital volume control?

2. Does the video mode reduce quality at all? If future DACs have this sort of latency, I don't think they could be used in a studio or gaming situations - as they need millisecond latency in the single digits.

3. That sounds good, thank you for clarifying. Would be interesting to see measurements, do you think using an ETC is a good way of testing temporal performance? There's a website called "Advanced Audio Analyser" that tests this way, which was the reason I switched to Chord as I compared standard filter DACs and NOS DACs to the Hugo - Hugo appeared to have almost identical timing measurements to NOS DACs, only without the aliasing and distortion issues.

4. Yes, I think with HD recordings there could be a sound quality benefit to extreme filtering of ultrasonics. Would you consider making such a HD filter in the future?

5. Yeah, I don't really trust their measurements tbh. They differ remarkably in output impedance from what the official specifications state. I know there can be margins of error, but not that large and I trust you and Chord to not falsely advertise. Maybe if Stereophile gets a hold of a Hugo 2 it could shut them up lol.

True Rob, regarding the last point. I thought I was onto something but you can't really calculate something in isolation of other metrics, I knew it was a failed attempt lol. I think if one were to formulate some sort of solid timing spec to aim for, we would need to do some sort of testing regarding human hearings ability to detect low-level transient error. It's possible the psychoacoustics scientific tests have already been done on this perhaps, I am not aware of them though.

I have a few more technical questions I would like to ask, if you are happy to answer them:

6. Regarding noise floor modulation, would LED displays dimming zones be a good comparison to explain its effects on audio (as they dynamically lower the absolute darkest shade it can reproduce)? I have always thought that LED displays look flat, with a lack of depth compared to emissive displays such as Plasma and OLED - even if say, an LED TV and Plasma TV has a similar black level.

Also, please can you confirm my understanding of noise floor modulations effect on the outputted waveform. As noise when outputting sinusoidal wave will be visible as small peaks and valleys on the "curved lines", even at its peaks. If the noise outputted is dynamic (noise floor modulation), I assume it will result in an alteration of the waves peak, aka the leading edge in musical terms? Is this why, perhaps, that noise floor modulation affects depth as it affects the consistency of waveform peak fidelity? Aka non-linear leading edge performance?

7. What do you make of "linear distortion shaping" I hear of some manufactures attempting to implement now? What I mean by "linear distortion" is that each harmonic component (2nd, 3rd, 4th etc) are at the same level at all power levels before clipping, while also being in the same ratio to one another. Do you think having linear distortion characteristics is something that is audible and one of the goals for neutral sound?

8. I'm sure I saw you mentioned somewhere that under a certain power rating, both the Hugo 2 and DAVE have genuinely zero distortion. Is this true and which number on the digital volume control?

9. I was talking to another manufacturer the other day about amplifiers and he mentioned, the wrong type or too much feedback can cause TIM (transient intermodular distortion). Do you measure your DACs for this?

10. What's the very maximum outputted power in VRMS from the Hugo 2s RCA output? The reason I ask is I want to know what gain setting my power amp should be set to.

11. Would you ever consider making a standalone headphone amp? For example, for people that want Pulse Array transparent sound but with their turntable, or more power for inefficient headphones such as HiFiMan Susvara?

1. The overload margin that I am talking about is within the first filter - and the 2.75dB margin was chosen as it suits the de-emphasis wich runs at 2048FS, as this requires a gain too, and the numbers cancel one another, so levels get restored. Now in principle, you need an overload margin that is the modulus of all your filter coefficients - but that ends up as a crazy number, that actually is impossible to trigger (I have tried). So to confirm that it was enough, I used test signals to determine what level was important; white noise needed +0.8dB; sine waves close to FS/2 +0.2dB; Gibbs phenomena with 8 kHz square wave was +2.41 dB; worst possible input signal from the AP was also 2.41 dB. So 2.75dB comfortably exceeds this level; also I tested with music, and it never came close to clipping. Once you are past the first WTA filter, then the volume control will give greater headroom.

2. Sure the video mode does sound worse than the full 1M taps; that's why I rip my blu-rays and play them back via J River, where the audio can be -0.63S delayed (so video is 0.63 S earlier) then I can run with full 1M taps. Blu ray sounds spectacular this way... This is why I want studios to adopt 768k as the primary standard, as then no delay.

3. Not familiar with that.

4. If FPGA capacity is not an issue I have pencilled that in as a future research exercise - but it will be unnecessary with Davina recordings, as this won't have added HF THD and noise.

6. You can see noise floor modulation in a number of ways - the whole noise floor pumping up and down, skirts on fundamentals, or certain bands, or noise floor mod that is slew rate related.... Conventional DAC's are full of this, and easy to see.

7. Not a good idea - HF distortion must be lower than 2nd or 3rd, and tail away to nothing. Also, distortion must sink into the noise floor as signal falls; distortion as a % must never increase with smaller signals.

8. If you run at or below +3dB (+6dB M scaler attached) you are in ultra low THD with Dave; Hugo 2 you are fine if not white on the volume.

9. Yes and he is incorrect in that the problem is not too much feedback. It's way too complex for that; and the Dave/Hugo 2 second order noise shaper pretty much eliminates HF distortion including TIM (and PIM) - and you can see this on the 19/20k two tone tests I have published - it's the cleanest by a huge margin against any other DAc at any price point.

10. Hugo 2 max voltage is 5.3v RMS at 1kHz.

11. No. It would degrade transparency with adding all those parts - but the Davina project is coming for analogue sources!

 

[flyte3333]

4. Yes, I think with HD recordings there could be a sound quality benefit to extreme filtering of ultrasonics. Would you consider making such a HD filter in the future?

Hi RAPGOD,

I know Rob already answered your quoted question.

But I thought this is what the 'green filter' of Hugo2 is for, so I've obviously not understood your question.

Can you expand more of your question? I'm just trying to follow along with your questions and Rob's answers

Cheers !

 

[paul2qute]

Hahaha


I just like learning


Robots won't take over the world lol. Both measurements and listening tests are important, that's what Rob does with his DACs and many other designers do. They both have their place and you cannot blindly follow one or the other. If people only "followed numbers" DAC technology would have barely advanced these last few years. Similarly, if people went the complete opposite extreme - hi-fi wouldn't have come this far and market fragmentation would be even worse than it is now, with designers building all sorts of weird, unnatural sounding equipment..

Also, you peg up "concert sound" as the ultimate goal. Most systems can reproduce concert recordings well, as they're not very taxing on a system. The most difficult music to reproduce as Rob Watts talks about - is un-amplified music, aka acoustic guitar, jazz and classical music etc.

Humans care little about distortion with unnatural processed music, as we have no absolute mental reference of what it's supposed to sound like. Well recorded vocals and un-amplified real music on the other hand, we do. Every form of distortion gets in the way of realism when it comes to these types of music/recordings. The quest for neutral, realistic sound is still ongoing, though in the DAC arena Rob Watts is leading. That's the whole point of his DACs...

Very good comments,but that's what I was trying to explain last night but failed miserably,because I don't know how instruments sound then using the USB connection if and I mean if it does add enjoyable sounding distortion that I wouldn't know the difference mate

 

[MikeRight]

Reflecting on my post earlier on..

I popped over to a local chord dealer today and listened to the Hugo 2 . A/B testing against a Mojo.
Listening to my Hd800S[s model] what I found was a pleasant surprise. The Hugo 2 does indeed widen the soundstage a little and give the low end a boost. I used the default settings, and didn't like the eq filters much.

Still a nice upgrade. Going back to the Mojo the HD800S sounded congested for a while until my brain adjusted :/

+1 For Hugo 2 it's pretty amazing but imo just a tad expensive given that down the road there may be battery issues.

I also tried the lcd3's out of my Mojo, and the Mojo drove them flawlessly. Mojo + Planar = great match. Just a shame the Hd800S requires that extra touch the Mojo can't supply adequately.

You have to try mojo + poly with 800s and you will discover that the performance is quite better than mojo alone. Not as good as Hugo2 of course but the difference is huge.

 

[Peter Hyatt]

With the replacement Polys universally successful, can 2Go be that far behind?

My wife, Heather is loving Poly.

 

[paul2qute]

With the replacement Polys universally successful, can 2Go be that far behind?

My wife, Heather is loving Poly.

I'm thinking Christmas for the Chord 2go,I rang Chord and asked but they wouldn't say,I did ask Mitch if he would tell John frank's to hurry up.He said he was gonna see him as soon as he put the phone down lol yeh right

 

[miketlse]

With the replacement Polys universally successful, can 2Go be that far behind?

My wife, Heather is loving Poly.

It may be a few months yet.
Chord have captured Lessons Learnt from the Poly launch, and I would have expected that one of them would be don't ship the product until both the apple and android control apps are ready.
If chord plan to use the same app for both the poly and 2Go, then maybe this would mean the 2Go is only the famous 6 weeks away from shipping.
However there has been no formal press release, and more importantly no whisper from chord about any beta-test campaign. I have got the impression that quite a few of the regular posters would like to beta testers, but chord has posted no public request for volunteers.
Possibly the earliest that we could hope for would be a press release at say the Munich High End Show in May, followed by shipping a few weeks later - but this is pure speculation by me as to possibly the most optimistic case.
More Lessons Learnt would be to perform long and thorough beta-testing, accompanied by a more low-key build up to shipping. The inevitable marketing enthusiasm that preceded Poly, backfired when there were shipping delays, and then the networking issues etc.
The result could be that shipping will be nearer end Q3, to catch the christmas sales.
Just my opinions, but I have explained my rationale.

 

[MikeRight]

The only thing I desire is getting at least the same improvement in the Hugo2 + 2Go as the one you get connecting Poly to the Mojo.
So impressive!

 

[paul2qute]

The only thing I desire is getting at least the same improvement in the Hugo2 + 2Go as the one you get connecting Poly to the Mojo.
So impressive!

How does it improve the sound mate,I thought it just makes the Hugo 2 more flexible

 

[Whazzzup]

Is the 2go out that no one knows about

 

[MikeRight]

I have tested Mojo & Mojo+Poly with 800s.
There is IMHO a huge difference in all bands in the second case.
+ More deep and controlled bass.
+ Mids and highs more rich and open.

In general, much more better than mojo alone.

 

[paul2qute]

I have tested Mojo & Mojo+Poly with 800s.
There is IMHO a huge difference in all bands in the second case.
+ More deep and controlled bass.
+ Mids and highs more rich and open.

In general, much more better than mojo alone.

Forgive me as I don't know how that is possible,when I asked Chord they said save your money as it won't improve the sound from using my laptop,they said if I wanna improve the sound then use hi res music

 

[Whazzzup]

Forgive me as I don't know how that is possible,when I asked Chord they said save your money as it won't improve the sound from using my laptop,they said if I wanna improve the sound then use hi res music

Well hi res is debatable. The benefits may not be audible in itself. But a quality server defiantly improves sq, regardless of the format. For example I upsample to dsd 128 to my TT, exquisit. But the files were simple Apple lossless till I dropped them on my server were it’s converted to flac.