Geek Pulse: Geek desktop DAC/AMP by Light Harmonics

[Semont]

  Is there any difference between the single ended and balanced line out? Is one better than the other?

One is subjectively better than the other.

 

[kostaszag]

 

  Is there any difference between the single ended and balanced line out? Is one better than the other?

One is subjectively better than the other.

Which one?

 

[NigelJ]

Is there any difference between the single ended and balanced line out? Is one better than the other?

The balanced output also provides twice the voltage and approximately four times the power, this is principally an advantage with high impedance or hard to drive headphones.

I say approximately four times the power as I am not certain if the Pulse is current limited when driving low impedance headphones in balanced mode.

 

[nudd]

It is current limited such that it will max out at 6W.

http://lhlabs.com/force/geekpulse/2146-pulse-x-output-levels-and-poweramp-stage-config

 

[m17xr2b]

I'm asking because some dacs have better sound quality(from what I have seen here) from balanced such as the Yggy and the single ended is more for convenience. I am planning to use the pulse with a DNA Stratus which only has rca inputs thus I need to know if I should go with something that has great quality from single ended such as a Hugo.

 

[wingsounds13]

I would say that the Pulse has the same quality from the balanced and unbalanced line outputs. As I understand they are separately buffered, but use the same type of components, just in balanced and unbalanced configurations as needed. This should be true of any kind of well designed source component, and one that delivers noticeably lesser quality from one or the other is not well designed or added the alternative output 'just because'.

The place where balanced has an advantage and should sound better is in the cables. Balanced cables are less prone to picking up EM and RF interference and are particularly preferred for long cable runs because of this.

J.P.

 

[Shawnb]

I would say that the Pulse has the same quality from the balanced and unbalanced line outputs. As I understand they are separately buffered, but use the same type of components, just in balanced and unbalanced configurations as needed. This should be true of any kind of well designed source component, and one that delivers noticeably lesser quality from one or the other is not well designed or added the alternative output 'just because'.

The place where balanced has an advantage and should sound better is in the cables. Balanced cables are less prone to picking up EM and RF interference and are particularly preferred for long cable runs because of this.

J.P.

 
What is considered a long cable run for audio? For headphone cables you're generally under 10 feet, I've always gone by the assumption 25+ feet is a long run and would need better shielding and anything under not so much.

 

[wingsounds13]

In the audiophile world I would seriously consider balanced cables for anything over 2M. Also worth considering even at only 1-2M. The environment around our systems can be rather noisy, particularly around computer workstations.

J.P.

 

[Semont]

 
Which one?

Sorry, that was a bit of a joke lol.
 
Objectively to the human ear, they won't sound any different. Of course, there will always be people who say otherwise.

 

[Narayan23]

Does anyone have further info on the DSD 256/Native DSD/Pure DSD  implementation timeline? Seems like we´ve been waiting eons for it.
 
http://lhlabs.com/forum/topic/progress-on-native-dsd-dsd-via-asio-2-2-for-windows-lhlabs-pure-dsd-dsd-256/

 

[WNBC]

New Pulse owner here.  Took some time off from Head-fi and the Pulse (basic level) is my first DAC since returning.  Purchased the Pulse from a friend who did not use it so I got it new in box.  I previously had the iFi Micro iDSD, Ciunas, W4S DAC-2, Anedio D2, Fiio X5, etc.  I like trying new things so I figured I'd give the Pulse a chance, especially purchasing at crowdfunding price.     
 
I still need to go through this thread in detail, but based on my thread searches, I must have chassis 1.0.  My LED is not blue like I see in the pictures, but more white/off-white and a very dim display at that.  Is that normal? Is there a setting for color and brightness that I am missing.  Not a deal breaker, but I like the brighter, blue display LED that I see in pictures by other Pulse owners.  I know many do not like bright LEDs, but this is very dim.
 
Based on what I have read, there is burn-in with this unit and I'm only a couple hours into it.  If the sound doesn't change dramatically I probably will sell it as I have liked my previous DACs much better.  Or, do most of you feel the amp section is not that great and I should pair it with an amp?  I have a Liquid Carbon arriving at some point in the near future.     
 
I will not give up on it yet, but I am curious to hear how dramatic the change in sound was for you all after burn-in and/or after pairing it with a good amp.

 

[Narayan23]

Hi WNBC! I have a Pulse XFI myself 1.0 chassis and yes the light is white and very dim. As burn in goes, the XFI started to sound better to me at around the 50 hour mark or basically after a week so I´d really let your Pulse burn in for at least that time before you give up on it.
 
What USB cable are you using? I only mention it because I have both the Light Harmonic 1G and 2G and the latter sounds better and in my case although it might seem strange, the 2G sounds better with the power leg disconnected.

 

[wingsounds13]

What Narayan23 said, plus...

Yes, the display is white and dim. Definitely give it plenty of burn in time before deciding on how much you like it. I would say at least two weeks of continuous operation - actively playing, not just power on. Sound quality will continue to improve through four weeks or more, although I found the changes past the three week mark to be minor.

The headphone amp in the Pulse is very nice, and I am certain that it will take a pretty good amp to best it but I am certain that the Liquid Carbon will be better.

J.P.

 

[WNBC]

Thanks Narayna23 and wingsounds13 for the responses.  I will definitely report back after a couple weeks of burn-in.  I am definitely ok with integrated HP amps.  My previous iDSD had a good internal HP amp.
 
Do not have boutique cables at the moment.  Standard stuff, sold off my Wireworld cables a while ago.  Maybe I'll grab another one of their USB cables.  To be honest, I have capped cable purchases at around $100.  Never had a super high end USB cable.  Something I would like to audition before spending 200-300.   Same goes for the linear power supply.  Probably would have been much cheaper if I got in on the crowdfunding prices. 
 
Macbook > Amarra > Vaunix Lab Brick USB hub > Pulse > Grado GH-1/Kam HP1/Savant

 

[NigelJ]

The blue colour of the display seen in photos is due to the different colour sensitivities of cameras and eyes. The dimness was as a result of requests by backers in the early campaign and on the old LH Labs forum who generally wanted a dim display.