[Tboooe]

So my Spring L3 has about 200 hours on it now and I absolutely love it!  Compared to my previous DAC the Spring sounds so much more organic and relaxed.  I am not really a fan of Diana Krall but through the Spring her smoky voice sounds just so real and inviting.  Its so easy to get drawn into the music because it just sounds right.  I am not sure if its because of the use of R2R, the overall implementation of the DAC, or both but the Spring to me seems to have such a nicely balanced sound, being both detailed and relaxed sounding in just the right proportions.  Needless to say I will be keeping the Spring for a while!

 

[T Bone]

  I am not really a fan of Diana Krall but through the Spring her smoky voice sounds just so real and inviting.  Its so easy to get drawn into the music because it just sounds right.

I really enjoy her "Wallflower" album and her Nat King Cole tribute album, "All For You".
 
I've been a big "Doug MacLeod" kick lately.  I love acoustic blues.  With the Spring DAC and good headphones, that natural "simplicity" of guitar, foot stomps and hand claps really shines.  It' a stripped down sound, but the detail is exquisite.  

 

[MacedonianHero]

   
I use a laptop as my source and had very poor results from the USB input alone.  I experimented with an Intona in/out of the signal path.
I wrote a post here that you might find interesting.  ....or PM with any specific questions.

 
Could be a really dirty source from your laptop? I've had some with really bad dynamics and hum with some of my laptops, who knows? From my iMac, the USB on this DAC is outstanding. 

 

[T Bone]

 
Could be a really dirty source from your laptop? I've had some with really bad dynamics and hum with some of my laptops, who knows?

Absolutely.  I pointed to that in my review as well.
For me, the telling point was how two different DACs dealt with the USB signal from the same laptop.  The Benchmark was awesome out of the box.  Whereas I needed to massage the USB signal to get the most out of the Holo.  
There's a reason so many Holo owners also seem to buy Singxer SU-1's 

I am glad to hear that you're satisfied with the USB interface.  I am very much looking forward to reading your review - I've read many of yours.  

 

[Tboooe]

Guys, what is the point of standby on the Spring?  When I put the Spring into standby I notice maybe a 1w difference in power consumption.  Given this tiny difference, is there any other benefit to Standby?

 

[T Bone]

  Guys, what is the point of standby on the Spring?  

One of the things it does is it keeps the USB port "powered up" so that your computer doesn't detect a USB disconnect event.  

 

[Tboooe]

  One of the things it does is it keeps the USB port "powered up" so that your computer doesn't detect a USB disconnect event.  

Thank you...since there is so little difference in power consumption a user should just leave it fully powered on and not bother having to remember to put it into and take it out of standby.  This is especially important for me because I have the display completely turned off and there is no other indicator of what mode its in.

 

[Energy]

Thanks for the reply T Bone. I'm unsure currently if adding so many linked parts would be a good thing for the digital signal.
 
The galvanic isolation of the Intona is no doubt better than that of the Singxer SU-1. I wish I could bypass the Singxer's. I don't feel incorporating two different galvanic isolation devices in series would be too beneficial. Seems like the two independent designs may flaw one another in the process somehow when it comes to spread spectrum. Being output a certain way by the Intona and having it revised by the Singxer in a way that might not be as good, or in this case, beneficial.
 
Another improvement I can see myself making is bettering the 5V rail of the Singxer SU-1. Cheap (but highly regarded) DIY linear power supplies like AMB Laboratories Sigma 11 (σ11) or any LPS for that matter that will provide low power noise in the single digits (μV). They all use large toroidal transformers so another chassis is required and the removal of the IEC power inlet of the Singxer SU-1 is needed for the power cable to enter.
 
I knew i shouldn't have sold my iFi iUSB... I would totally have removed the Singxer's power supply PCB and replaced it with the internal board within the iFi iUSB. Connect it's 5V USB output to the mainboard, and bam! 0.1μV of noise. Not too sure if a better power supply will warrant any sound improvements for this unit, although I have seen some people doing this on other forums and hearing good from their experiments.
 
Just food for thought. I will give it a shot whenever I have a chance. I still think my idea with the iFi iUSB is gold. Maybe I can find a used Intona Isolator. If it gave you an improvement T Bone, then I believe I should give it a chance. But the question is, do you feel the improvement the Intona Isolator gave was worth an additional $250?

 

[T Bone]

  a user should just leave it fully powered on and not bother having to remember to put it into and take it out of standby.  This is especially important for me because I have the display completely turned off and there is no other indicator of what mode its in.

I'm with you.  I can not physically reach the power switch in the location where my spring sits.  It's on a bookshelf in my office.
I leave the unit powered on 24/7 and just use the standby mode when not in use.   With the display completely dimmed there's no indication the unit is powered on.  
It would be nice if there was a power on LED and/or standby indicator on the front panel.

 

[T Bone]

  Thanks for the reply T Bone. I'm unsure currently if adding so many linked parts would be a good thing for the digital signal.
 
The galvanic isolation of the Intona is no doubt better than that of the Singxer SU-1. I wish I could bypass the Singxer's. I don't feel incorporating two different galvanic isolation devices in series would be too beneficial. Seems like the two independent designs may flaw one another in the process somehow when it comes to spread spectrum. Being output a certain way by the Intona and having it revised by the Singxer in a way that might not be as good, or in this case, beneficial.

I agree.  I'm not a fan of having two devices "daisy chained" together.  If I could only have one device, it would be the Singxer SU-1.  
I would break out my AMEX card for the illegitimate love child of a Singxer & Intona drunken romp.  

   That would be the best of both worlds!
 

  Another improvement I can see myself making is bettering the 5V rail of the Singxer SU-1.

 
It looks like @bimmer100 is already on it.  He's got a Singxer SU-1 with a modded power supply that boasts 3.uV output noise.
Check it out here
 

  But the question is, do you feel the improvement the Intona Isolator gave was worth an additional $250?

Are there benefits of daisy chaining an Intona/Singxer?  It made a difference with my laptop.  Did it make $250 difference.  "meh"  
 
If you can pick up a used Intona give it a try.  See if it makes a significant differences in your rig for the $$.  

 

[Tboooe]

@T Bone @Energy I am planning on doing a few things that may improve the SU-1.  I will be purchasing an Upton Audio LPS-1 and using it to provide clean 5v directly to the SU-1 as well as the USB power.  I am hopeful this will improve things.

 

[Energy]

  I agree.  I'm not a fan of having two devices "daisy chained" together.  If I could only have one device, it would be the Singxer SU-1.  
I would break out my AMEX card for the illegitimate love child of a Singxer & Intona drunken romp.  

   That would be the best of both worlds!
 
It looks like @bimmer100 is already on it.  He's got a Singxer SU-1 with a modded power supply that boasts 3.uV output noise.
Check it out here
 
Are there benefits of daisy chaining an Intona/Singxer?  It made a difference with my laptop.  Did it make $250 difference.  "meh"  
 
If you can pick up a used Intona give it a try.  See if it makes a significant differences in your rig for the $$.  

 
Agreed. I'd buy a "Sintoxerna" in a heartbeat. Top notch galvanic isolation and femto clocks. 
 
Thanks for the link but I don't believe that's the type of modification that will offer significant improvements let alone an improvement at all.
Seems more tailored for boutique parts than anything. The same power supply board is used. German WIMA film capacitors are used over the generic Chinese ones. (+1) Japanese Panasonic Fine Gold (FG) replace FC which wouldn't be ideal, as FG works better in analog circuit. (-1) The stock FC should be better rated... If one were to improve these capacitors, Panasonic FR should have been chosen for low ESR and ripple current. Not trying to bash ones product, I just don't see where this could help.
 
I'm going to take a wild guess that no real changes were made to the power supply and it already outputs around 3μV noise.
 
If this were the case, I think I'm going to dismiss my experimentation with the power supply upgrade. I am doubtful that I will hear 0.1μV vs 3μV of noise. Anything heard would fall more on the line of placebo.
 
@Tboooe - Now that's something I really want to see. Improving the power supply I can care less at the moment given what i wrote earlier, but providing a cleaner 5V for the USB power input should be beneficial. Like with how the Intona Isolator receives power from the USB input for it to work, the Singxer SU-1 looks like it also use the voltage from the USB input. The Intona receives 500mA of current from the USB 2.0 connection and spits out 300mA at the output so it still works in series with the Singxer SU-1 as I'm sure the Singer SU-1 use less than 200mA worth of current. After all, the Intona Isolator is larger with dual FPGA's. My guess is the Intona device improve further on galvanic isolation and also provides the Singxer-SU1's USB input with a cleaner power supply from it's built in internal linear power rails. I can understand why the addition of the Intona Isolator would be a slight improvement now, based on T bone's hearing impressions.

 

[inthere]

What is the optimal burn in time for the Spring?

 

[Tboooe]

What is the optimal burn in time for the Spring?

Mine really sounded great after 100 hours.

 

[Superdad]

.... Like with how the Intona Isolator receives power from the USB input for it to work, the Singxer SU-1 looks like it also use the voltage from the USB input. The Intona receives 500mA of current from the USB 2.0 connection and spits out 300mA at the output so it still works in series with the Singxer SU-1 as I'm sure the Singer SU-1 use less than 200mA worth of current. After all, the Intona Isolator is larger with dual FPGA's. My guess is the Intona device improve further on galvanic isolation and also provides the Singxer-SU1's USB input with a cleaner power supply from it's built in internal linear power rails. I can understand why the addition of the Intona Isolator would be a slight improvement now, based on T bone's hearing impressions.

 
Sorry, that is incorrect. No DAC provides VBUS power to an upstream connected device. Both sides of the Intona's single board are powered via the VBUS from the computer.

In the below photo you can see the Coilcraft transformer sitting at the bottom, across the moat. This is how they transfer VBUS power across without loosing the galvanic isolation. It is also why their VBUS power (when connected to a standard 500mA limited computer USB host port) is limited to 300mA.  
(Sadly, they also place the one clock--which is used for both FPGAs--on the upstream "dirty" side. And then the Silicon Labs digital isolators use add jitter. Hopefully they do some sort of further rechecking in the downstream FPGA, but it must still be based on the clock coming from the upstream side through the isolators.)

Don't get me wrong, the Intona is effective as a galvanic isolator (I've had one for over a year). But it sure sounds a lot better with a REGEN (powered by an LPS-1 so as not to defeat the isolation) after it.  

 
The benefit of USB isolation and reclocking is separate from the improvement of USB 5VBUS.  Improved USB signal integrity (as see in an eye-pattern) and impedance match are of benefit because it results in the USB input PHY of the DAC (or DDC) generating less of its own packet-data noise and ground-plane noise--pernicious stuff that often sails right on through the DAC or DDC's own digital isolators, resulting in perturbation of the master audio clock--thus adding jitter which can be audible.
 
There are multiple factors at play in digital audio chains.  Clarity comes from not conflating them into one pile. 

 
By the way, I am enjoying my Holo Spring Level 3 more each week.  And Tim promised to ship me an SU-1 (in trade for the second UltraCap LPS-1 he recently bought) as soon as he has stock again.  I am anxious to use the I2S link between them.  And yes, I'll quite likely mod it to run from the 100% leakage-current-blocking LPS-1.  But I bet @Tboooe will beat me to it on that!
 
Best,
--Alex C.