Light Harmonic Geek Linear Power Supply (LPS and LPS4) Impressions/Discussion

[doctorjazz]

I think you're right, made an error. That's what happens when I rush into things.

 

[m-i-c-k-e-y]

Get a barrel to usb adapter and work from there

Sent from my SM-N9005 using Tapatalk

 

[Chefano]

Get a barrel to usb adapter and work from there

Sent from my SM-N9005 using Tapatalk

Only if his Jays is 5V and actually won't have the same result, there is a digital part in Geek LPS and Wyrd that receives and retransmits the data (repeater).

 

[doctorjazz]

Anybody interested in a Jays LPS?

 

[Audio Addict]

It is not compatible with the Geek Out using Windows and jriver. The driver does not recognize it with using their slacker cable.

 
At the suggestion of a LH Forum user, I tried the GO direct and it worked.  LPS4 and slacker didn't talk.

 

[miceblue]

This was just posted on LH's YouTube channel.

[video]https://www.youtube.com/watch?v=jRSxmE-FPDU[/video]


I'm not sure if this has to do with USB 1.1 (Class 1) vs USB 2.0 (Class 2) devices, but that's an interesting thing to note.

 

[Chefano]

This was just posted on LH's YouTube channel.


I'm not sure if this has to do with USB 1.1 (Class 1) vs USB 2.0 (Class 2) devices, but that's an interesting thing to note.

Miceblue I found my old UD110v2 at my drawer... and why not to test it!?
To my  surprise it works, and Im really enjoying the sound right now.. its an USB 1.1 device.
I think Larry told the truth.

 

[uncola]

So I have an LPS I bought to use with my geek pulse infinity but I upgraded to vi dac.. are there any currently shipping 12v amps I could get to use with the LPS?  Not geek pulse, an amp only with no dac

 

[wingsounds13]

Only if his Jays is 5V and actually won't have the same result, there is a digital part in Geek LPS and Wyrd that receives and retransmits the data (repeater).

I know that this response is a bit late, but...

As I understand it the Geek LPS does not have a repeater in the USB data line, it is just a signal pass through. This is the big difference between the Geek LPS and the Schiit Wyrd. The Wyrd has a clean repeater and a clean power supply for the USB device, where the LPS has a simple signal pass through and an ultra low noise power supply for the USB device. This makes me think that the ultimate combination would be a split cable with the data coming through the Wyrd and the power coming from the LPS.

This data pass through makes me wonder why it would not work with USB 1.1 compliant devices - the problem cannot be the slower data rate. It must have something to do with grounding and perhaps the relative signal/ground levels. My thought is that the real culprit is the USB DACs that do not work do not have proper balanced receivers on the data lines, but I have no information to back up that idea.

J.P.

 

[uncola]

woot I found something that uses a 12v dc input that I think will work with my 12v LPS.  
 
a NOS dac http://www.ebay.com/itm/Non-Oversampling-NOS-DAC-TDA1543-DIR9001-SPDIF-Coax-Optical-dual-9V-NiMH-w-charg-/201003880227?pt=LH_DefaultDomain_0&hash=item2eccc3cf23
 
doctorjazz there's one available for sale on the classifieds for $175 if you want to use your Jay's on something

 

[doctorjazz]

woot I found something that uses a 12v dc input that I think will work with my 12v LPS.  

a NOS dac http://www.ebay.com/itm/Non-Oversampling-NOS-DAC-TDA1543-DIR9001-SPDIF-Coax-Optical-dual-9V-NiMH-w-charg-/201003880227?pt=LH_DefaultDomain_0&hash=item2eccc3cf23

doctorjazz there's one available for sale on the classifieds for $175 if you want to use your Jay's on something

That's sooooo nice, really appreciate the thought. Someone who had use for it already bought it from me. But thanks so much for thinking of it.

 

[slingshot80]

  Hi, it was defective. I am sending it back today, 2 Day Priority Mail, prepaid postage.

 

Hello, I received my LPS-4 today so it took them over a month to send it back. Will try it probably tomorrow.

 

[miceblue]

I received the LPS4 back from the LH Labs repair center.

Repair Technician Comments:
Fixed buzzing issues.
Fixed USB B grounding.
Fixed competitions dac's syncing at power up.

Buzzing issue is gone!
MacBook -> USB A-USB B cable -> Geek LPS4
Geek LPS4 + DC barrel polarity inverter adaptor -> STAX SRM-252S
Geek LPS4 -> slacker cable -> Geek Out 1000 -> 3.5 mm-RCA cable -> STAX SRM-252S -> STAX SR-207

Turning on the STAX amp when connected to the LPS4 yields a brief (< 1 second) buzz sound, but it goes away after that.



Impressions when switching the power supply to my STAX amp from the Toyozumi step-down transformer and stock STAX AC/DC wall adaptor to the LPS4:

• Bass-midrange transition seems less boomy, more defined and slightly warmer
• It might be due to the mastering of the particular tracks I listened to, but the treble seems a bit more edgey to my ears; perhaps this is more how the music is supposed to sound
• Soundstage seems to open up a bit and instrument separation increases

USB output of the LPS4 now works with the Objective DAC, and should work with other USB 1.1/USB Audio Class 1 devices.
jbr1971
Do you know if a future LPS revision will have a floating ground switch? I don't know if that is related to this newfound ability to use USB Audio Class 1 devices with my LPS4.
http://support.lhlabs.com/support/solutions/articles/5000552331-my-usb-1-1-dac-will-not-work-with-the-lps-lps4-however-my-usb-2-0-dac-s-will-why-



Geek Out now gets recognised by computer even if it's connected to the LPS4 before being turned on. Previously, you would have to unplug/replug any attached USB DACs because
http://support.lhlabs.com/support/solutions/articles/5000548516-i-powered-down-the-geek-lps-with-the-geek-out-pulse-connected-and-when-the-geek-lps-was-powered-back

When the Geek LPS is powered back on, the firmware initializes and misses the handshake attempt from the Geek Out/Pulse to the computer.

My LPS4's box also came with a new security seal sticker, extended warranty card, and an HD Tracks discount voucher! I wasn't expecting that.

 

[DiscoSmoke]

Sounds like they jumpered the USB to chassis ground. Would rather they installed a switch.

 

[miceblue]

Sounds like they jumpered the USB to chassis ground. Would rather they installed a switch.

From what I read in the Geek Force, someone else had the same buzzing issue as me and reported that the technician notes for their repaired unit was that, indeed, they connected a resistor from the USB board to the LPS's chassis.
http://lhlabs.com/force/techsupport-geeklps/3071-lps4-grounding-problem-with-usb-output?start=125#60486