[krikor]

  Not true, the X will be fully mono. The fi adds femto clock and upgraded components plus more digital inputs.
 
http://lhlabs.com/geekpulse3/images/Geek_Pulse_Soul_Technology_Breakdown.pdf

Correct on the fully mono. But where are you seeing more digital inputs? They are shown to be the same across all of the models - 1 USB, 1 TOSLINK, 1 AES/EBU, 2 SPDIF Coax.
 
 
As for how the transconductance amp is upgraded, that technology breakdown is not exactly clear. I thought different opamps were being used, but the same are listed across all the models from Pulse X through Soul:
OPA1612, LM4562, TPA6120A2, LME49990, AD827
 
 
And perhaps the following has been covered before, but it just crystalized for me looking at this chart:
 
There is an interesting situation for those who are considering the Soul - no single-ended headphone output is provided. You must have headphones wired for balanced use (no, a simple 1/4" TRS to 4-Pin XLR adapter will not do it since the TRS shares a common ground between the left and right channels). May not be a concern for those who can afford the Soul as many will already have balanced cans, and it is intended as a DAC and not necessarily a headphone amp. But I have several different pairs of cans, some that can be easily wired for balanced use (Sennheiser), others that need modification (Beyerdynamic).
 
Also, correct me if I'm wrong, but given that the headphone out is only balanced, you will not be able to listen to the tube output stage of the Soul Tube via headphones (unless of course you connect the single-ended outs to a separate headphone amp).

 

[FraGGleR]

  What's the jury on the upgrades the Pulse Xfi brings over the Pulse X? All I could gather is that internal (passive and active) components have been upgraded and you get the Femto clocks instead of the TCXO. The pdf of the key features of the models only notes that the transconductance amp has been upgraded and we get the Femto clocks. Is there any other info on the difference between these models? My friend, who is better informed than me, is skeptical that the Femto clocks will make an audible difference alone, so that leaves the other upgrades to make the difference sound quality wise. Are the changes worth the current $622 upgrade from Pulse X to Pulse Xfi? I am sure they are worth considering the retail price difference between the models, but how about the campaign price of the models: the X - $777 and the Xfi - $1399? What are your opinions, can someone chime in? 

  
Only you can decide if it is worth it, right?  The upgrades do make the Pulse Xfi better in theory, but as your friend pointed out, we might not hear the differences.  And each person will hear those differences differently and to different extents and will have to assign their own dollar values to those differences. 
 
Curiosity got the best of me, so I ordered both a Pulse X and an Xfi so I could compare them myself.  I will sell off whichever one presents the least value for me.  I am 100% positive there will be someone who will feel the exact opposite of me.  

 

[FraGGleR]

  You all have been waiting for over a year?
 
Feel sorry for those who put down more than $1.00...

Why?  

 

[jexby]

Why?  

Because we didn't get immediate gratification of buying off the shelf.
And instead paid around $600 for a product that's going to sell at 2x-4x the price.

 

[germay0653]

  Not true, the X will be fully mono. The fi adds femto clock and upgraded components plus more digital inputs.
 
http://lhlabs.com/geekpulse3/images/Geek_Pulse_Soul_Technology_Breakdown.pdf

I stand corrected.  I was thinking of the Wave!  My mistake.

 

[germay0653]

  Correct on the fully mono. But where are you seeing more digital inputs? They are shown to be the same across all of the models - 1 USB, 1 TOSLINK, 1 AES/EBU, 2 SPDIF Coax.
 
 
As for how the transconductance amp is upgraded, that technology breakdown is not exactly clear. I thought different opamps were being used, but the same are listed across all the models from Pulse X through Soul:
OPA1612, LM4562, TPA6120A2, LME49990, AD827
 
 
And perhaps the following has been covered before, but it just crystalized for me looking at this chart:
 
There is an interesting situation for those who are considering the Soul - no single-ended headphone output is provided. You must have headphones wired for balanced use (no, a simple 1/4" TRS to 4-Pin XLR adapter will not do it since the TRS shares a common ground between the left and right channels). May not be a concern for those who can afford the Soul as many will already have balanced cans, and it is intended as a DAC and not necessarily a headphone amp. But I have several different pairs of cans, some that can be easily wired for balanced use (Sennheiser), others that need modification (Beyerdynamic).
 
Also, correct me if I'm wrong, but given that the headphone out is only balanced, you will not be able to listen to the tube output stage of the Soul Tube via headphones (unless of course you connect the single-ended outs to a separate headphone amp).

Breakdown for the OpAmps:
 

The upgrades cover op-amps in the most critical current to volgate and first stage of amplification

Here is the final list of OpAmp we picked for "Upgrade perks".

Analog Output Stage (Bias into Class A)
* AD827 in [Geek Pulse] and [Geek Pulse S]
* LME49990 in [Geek Pulse X]

Current to Voltage Conversion
* OPA1612

Upgrade the amp of DC Servo too.... LM4562, it is.​

 

Source of info:​

 
https://docs.google.com/spreadsheet/ccc?key=0AljAXIFo7qVqdFdmVUoxOXB1VzFPaGtkQXdRa01ibUE#gid=1

 

[eac3]

 
To answer your last question, IMO , yes and it's a matter of degrees of improvement.  The PC, internally, is notorious for emitting all kinds of RF and EMI.  

 
I guess a general follow up question, that will help me tie up this confusion. If the signal is affected for RF and EMI somewhere in the chain (i.e. the source/PC),  but the other half, or third, or X% of the chain is not due to the necessary precautions...such as split USB cables for example,...does it still not matter if part of the chain was affected from RF and EMI?
 
My understanding from your explanation leads me to believe that the data signal can be affected by the PC...but once it leaves the PC, the signal goes back to its original form due to a split USB cable....how does the cable somehow reconstruct the original signal?

 

[FraGGleR]

Because we didn't get immediate gratification of buying off the shelf.
And instead paid around $600 for a product that's going to sell at 2x-4x the price.

Man, when you put it that way, I do feel sorry for myself...

 

[germay0653]

   
I guess a general follow up question, that will help me tie up this confusion. If the signal is affected for RF and EMI somewhere in the chain (i.e. the source/PC),  but the other half, or third, or X% of the chain is not due to the necessary precautions...such as split USB cables for example,...does it still not matter if part of the chain was affected from RF and EMI?
 
My understanding from your explanation leads me to believe that the data signal can be affected by the PC...but once it leaves the PC, the signal goes back to its original form due to a split USB cable....how does the cable somehow reconstruct the original signal?

No, it doesn't go back to it's original form but there is no more "damage" done to the signal from that point forward.  One can go to extremes.  Some people use Linear Power Supplies to power their PC's to provide the "cleanest" power going in but most motherboards and internal components weren't designed for audio playback. 
 
Bear in mind, your PC wasn't designed to just play audio so in most cases the EMI and RF interference isn't causing degradation.  As an example, using a spreadsheet program like EXCEL isn't like to be adversely affected by it. 
 
I imagine LH Labs, specifically Larry Ho, when designing the Source, a purpose built computer for audio, will use components and layout the PCB (motherboard) where these components are located with these considerations in mind as he is very aware of their adverse affects.

 

[eac3]

 
No, it doesn't go back to it's original form but there is no more "damage" done to the signal from that point forward.  One can go to extremes.  
 

 
Thank you very much germay.

 

[greenkiwi]

There is an interesting situation for those who are considering the Soul - no single-ended headphone output is provided. You must have headphones wired for balanced use (no, a simple 1/4" TRS to 4-Pin XLR adapter will not do it since the TRS shares a common ground between the left and right channels). May not be a concern for those who can afford the Soul as many will already have balanced cans, and it is intended as a DAC and not necessarily a headphone amp. But I have several different pairs of cans, some that can be easily wired for balanced use (Sennheiser), others that need modification (Beyerdynamic).
 
Also, correct me if I'm wrong, but given that the headphone out is only balanced, you will not be able to listen to the tube output stage of the Soul Tube via headphones (unless of course you connect the single-ended outs to a separate headphone amp).

 
Correct on the tubes not being in the path to the headphones, which I think is a really big bummer.  I would rather have a SE headphone output with tubes, or selectable tubes than a balanced w/o tubes.
 
As for the connector.  I imagine that you could have an adapter that used the shell of the XLR for ground.  You'd pull the positive R & L and use the shell as a common ground.

 

[mandrake50]

And instead paid around $600 for a product that's going to sell at 2x-4x the price.

Maybe.. from what I have seen, the Geek Out is not fetching what they projected would be full list.
We have no clue whether the list that they show now will ever be supported in the market.
Looking at it that way sure does make one feel better and is the way they get people to buy into these "perk" schemes...
But it may well be just marketing speak in the end.

 

[DSlayerZX]

Because we didn't get immediate gratification of buying off the shelf.
And instead paid around $600 for a product that's going to sell at 2x-4x the price.

 
 
Well...some of my other hobby is much, much more geeky.
 
To some people, they just want instant gratification on everything, but for some other hobbies... it's almost always "the wait game"
 
The practice of pre ordering for something that cost 200+ then having to wait for another year to receive them is very common.
 
Let along delays, missing shipment, natural disaster that delay production, etc, etc etc.
 
So for some people, we are already used to it by now.
 
Though seeing how many ppl get riled up and being angry on production delay did entertained me to a certain degree.

 

[FraGGleR]

Maybe.. from what I have seen, the Geek Out is not fetching what they projected would be full list.
We have no clue whether the list that they show now will ever be supported in the market.
Looking at it that way sure does make one feel better and is the way they get people to buy into these "perk" schemes...
But it may well be just marketing speak in the end.

Based on current IGG pledge levels, the original early backers should probably feel good about a 2x return if they sell. But I certainly don't expect to see anything close to retail pricing on the used forum.

 

[pauldgroot]

Check the table I posted above..