[etnt]

From rob's earlier post on the same subject
https://www.head-fi.org/threads/cho...official-thread.831345/page-275#post-13534747

 

[flyte3333]

With Hugo 1 galvanic isolation made huge differences to the SQ; and this was down to noise entering into Hugo's ground plane - and this noise was from two sources - the direct connection of the grounds from source to Hugo, and noise due to the decoding USB device as it unscrambles the USB data and buffers it to then feed it to the FPGA, with the FPGA supplying the clock.

The direct ground connection has been isolated by using RF filters, both on the ground and VBUS of the USB - this very effectively isolates Hugo 2 from the source ground. The USB decoder chip has a more efficient PSU, and full RF filtering, so noise from the decoding is also isolated from Hugo 2 analogue electronics. Moreover, Hugo 2 DAC and amplifier section is much better isolated from the battery, and we can see that from the stereo separation figures of better than 144 dB - and that's driving a 33 ohm load. You can see the separation (which actually indicates how well Hugo 2 is isolated from the power supplies) on this slide here:

Indeed, following the listening tests on Hugo 2's inputs I did (briefly) entertain the idea of not doing galvanic isolation for non-portable DAC's. Indeed, if Hugo 1 was as well isolated as Hugo 2, I would not have bothered to develop the galvanic isolation I currently use.

So to answer your question - with Hugo 2 the benefits of galvanic isolation has been reduced by at least an order of magnitude; if you are using HP, then don't worry about it all as it is a non-issue; if you are feeding power-amps then it can make a small improvement. Of course, YMWV as differing sources and different power amps will have different sensitivities. You can test this out by listening to USB or optical - if they sound the same, then you have no problems, and do not need further treatment at all.

Rob

Hi Rob

Do you have the same stereo separation measurement for Dave driving a 33 ohm load?

JA's Stereophile review says "Channel separation was superb, at >125dB in both directions below 1kHz, decreasing to a still-excellent 95dB at the top of the audioband."

https://www.stereophile.com/content...da-processor-measurements#E2lX3XI8LaOWIBvX.99

Does this means Hugo2 has better measurements than Dave on channel separation?

Cheers

 

[Rob Watts]

Hi Rob

Do you have the same stereo separation measurement for Dave driving a 33 ohm load?

JA's Stereophile review says "Channel separation was superb, at >125dB in both directions below 1kHz, decreasing to a still-excellent 95dB at the top of the audioband."

https://www.stereophile.com/content...da-processor-measurements#E2lX3XI8LaOWIBvX.99

Does this means Hugo2 has better than Dave on channel separation measurements?

Cheers

Not to hand; the ch sep measurements themselves are not important; what is important is crosstalk distortion; and zero crosstalk distortion means that the PSU is not inducing distortion itself; so my testing for crosstalk on Hugo2 was to test to see how low the distortion was from the PSU. Dave on the other hand has ultra low PSU impedance, so will not suffer from this problem.

 

[rkt31]

@TKpurple, I initially used and RCA to XLR adapters but they had ground and negative pin shorted inside. later on I got custom furutech interconnect made where in the shield wire of cable kept floating at RCA end and connected to ground pin at XLR end.

 

[flyte3333]

Not to hand; the ch sep measurements themselves are not important; what is important is crosstalk distortion; and zero crosstalk distortion means that the PSU is not inducing distortion itself; so my testing for crosstalk on Hugo2 was to test to see how low the distortion was from the PSU. Dave on the other hand has ultra low PSU impedance, so will not suffer from this problem.

Thanks Rob.

 

[rkt31]

I was one of few in this forum who suggested benchmark ahb2 to use directly with chord DACs as rob watts once suggested to use the volume control of Hugo directly into power amp to avoid an active component in the chain. I have happy that I went that way because the system is now clutter free. even mojo is extremely good to feed this benchmark amp.

 

[rkt31]

the beauty of chord DACs are is the inbuilt volume control combined with ultra low output impedance. benchmark ahb2 variable gain setting goes very well with such DACs. for other DACs use of preamp ( both active and passive have their own plus minus) is unavoidable. adding pre will only color and reduce the transparency.

 

[JaZZ]

Keep it on, desktop mode keeps the voltage on the battery at a safe level for longevity POV, and ensures that the bulk of the current needed for Hugo 2 comes from the charger not the battery.

What about the longevity of the electronics?
How much current does the Hugo₂ consume during inactivity? After all it stays quite warm, so the heat is produced by the used current, obviously. From an ecological POV I'm inclined to just turn it on when I use it.

 

[skypablo]

While learning to love the Hugo2 (...it is a very simple task) I have built a sloped support/holder for it using the 3d printer. It is sitting over the rega and let me look at it ))

 

[Satir]

n/a

 

[NoTimeFor]

Rob, with desktop mode, will win benefit from using an after market charger like ifi ipower?

Also, will chord provide replreplacem batteries in future?

 

[Peter Hyatt]

A lot of questions re battery life. As I shared privately, my belief is that H2 battery will go well beyond 10 years. My reference point is long term use of Li battery products, including a pitching machine that is near 10 years and working fine.

I was using H2 only in desktop mode for quite some time but have been on the go more of late. I think 2Go is going to mean most of its use via SD card for me.

If there are recommendations for charging for the OTG, I appreciate it. I don't know if going from Desktop to portable and back again will have significant impact on battery life, so I appreciate the input here on the forum.

skypablo, how cool is that!

 

[asia]

A lot of questions re battery life. As I shared privately, my belief is that H2 battery will go well beyond 10 years. My reference point is long term use of Li battery products, including a pitching machine that is near 10 years and working fine.

By accident I left a piece of Li powered sports equipment in the sun in my parked car. The unit stopped working. The manufacturer said the battery has a protective thermal cutoff that might have tripped. I am now trying to be more careful my portable equipment.

 

[asia]

... But the treatment still means that DSD changes does not create clicks and pops. It took quite a lot of effort to mute when DSD changed, but to be tolerant of small errors in the data.

This quote is from the Qutest official thread. I appreciate the clean, basically noise free DSD track changes on my Hugo 2. Especially for classical ensemble music where the artists don't stop playing between movements this feature is very helpful. An example: CCS_40318 Le Quattro Stagioni, DSD 256fs, track 11 to 12. Thank you Rob.

 

[Ike1985]

"Keep it on all the time."

Yeah, but..unplug, unplug, unplug when storms headed your way and/or you'll be away from home and storms forecasted. Remember more than few incidents in Florida of audio gear ruined by lightning. Even recommended surge protectors may not protect your gear. Suggest reviewing ones insurance policies and take appropriate action to insure against losses. (;

Or listen via Bluetooth. = )

Rob,

I had an anomaly happen to me while listening to my Hugo2 via Bluetooth. Not sure if it was from my headphones, cable or the H2. It was in the left ear only, sounded like a loud pop, like someone put a bucket over my head and head it with a drumstick but again it was in the left side only. It was quite a bit louder than the music and quite startling. I've probably listened to Hugo hundreds of hours and never heard anything like this. Actually my left ear is hurting a bit from it. I took the song back and tried to replicate it but was unable to. I was using my 64 Audio A18's and the Hugo was not plugged into a charging source it was running off battery. Hope everything is fine, anyone know what it might have been? I also tried wiggling my headphone connector and was not able to reproduce the effect.