[mandrake50]

I guess the fact that you can drive a set of headphones from either output and have full volume control leads me to think that both are amplified outputs rather than a true  (usually fixed and at reference level) line outs. I think I recall them billing this as a device that would drive two sets of headphones at once.
 
Don't they recommend using the 47 Ohm output to drive an external amp ? So it will do it .. but  with "double amping" going on.

 

[zerodeefex]

I use the GO450 with a Vali and it's a pretty solid combo.
 
In fact, my current main desk rig at work is a Wyrd > GO450 > Krell Klone > Paradox Slants/AD2000/HD800s while waiting for a fully kitted Pulse to take over DAC duties.

 

[pearljam50000]

You dont mind about the double amping?

 

[miceblue]

You dont mind about the double amping?

Who said it's double amping?

 

[mandrake50]

Who said it's double amping?

I mostly just read around the forums, but I have seen the term "double amping" used when people are referring to driving the input of an amplifier from the output of another amplifier. In this case, the amplified output of the GO driving the input of the Vali.
 
If that is the correct definition, then what you mentioned doing is "double amping".

 

[miceblue]

Who said it's double amping?

I mostly just read around the forums, but I have seen the term "double amping" used when people are referring to driving the input of an amplifier from the output of another amplifier. In this case, the amplified output of the GO driving the input of the Vali.

If that is the correct definition, then what you mentioned doing is "double amping".

That definition is true, but who said the Geek Out's 47-ohm output is being amplified? If it's not, then it's not being double amped in that case.

 

[mandrake50]

It is amplified.  If yours is labeled like the one I have you will see two icons on the back side right above the output jacks. Both are headphone icons, one thicker or more bold than the other. This indicates they are for use with low or higher impedance headphones. The 47 ohm output is  recommended for line out duties as well. I am sure that this is because it is a better match for the typically high impedance inputs of other amplifiers. This is typically 10K Ohms.
 
Plug a set of headphones into the 47 Ohm output, fire up some music, play with the volume control. Let me know what happens. Does it drive the phones to a similar level as the 0.47 Ohm jack? Do a quick A-B comparison. In my case it drives the HE-400 just as hard out of either, though it does sound different due to damping factor differences (especially with higher Z phones like the HD 650).
 
If that is not an amplified output, then I am confused about what that term means.  It sounds like the definition of an amplified output to me.
 
Who said this you asked.
 
All of the people, including LH Labs, that say that the 47 Ohm jack can be used for higher Z headphones are essentially saying that it is an amplified output. You can find many reviews and even descriptions directly from LH Labs that make this statement.
 
Here is one:
 
http://www.audiostream.com/content/lh-labs-geek-out-1000-dacheadphone-amplifier
 
There's on-board volume controls and little LEDs that indicate what sample rate you're currently playing and two 3.5mm analog outputs, 47 Ohm for the line out and higher impedance headphones and 0.47 Ohms for lower impedance headphones.
 
Or this from the GO Kickstarter page:
 
Problem - You want to share your music with a friend.  So, you hand him or her one earbud, and you listen to the other.  That sucks!

1. It's a shareulator.  GEEK has two headphone jacks!

 
Of course, an amplified headphone output can act as a psuedo line output to drive another amp, as long as it can swing the required voltage into the HiZ load, but it is still an amplified output. This means using it for this purpose is "double amping"!
 
If you are interested take a look at this article:
http://www.audiostream.com/content/lh-labs-geek-out-1000-dacheadphone-amplifier
 
While the GO 47 Ohm output can be used to drive an amp, it is not anything even close to a true line output.

 

[miceblue]

Spoiler: explanation

It is amplified.  If yours is labeled like the one I have you will see two icons on the back side right above the output jacks. Both are headphone icons, one thicker or more bold than the other. This indicates they are for use with low or higher impedance headphones. The 47 ohm output is  recommended for line out duties as well. I am sure that this is because it is a better match for the typically high impedance inputs of other amplifiers. This is typically 10K Ohms.

Plug a set of headphones into the 47 Ohm output, fire up some music, play with the volume control. Let me know what happens. Does it drive the phones to a similar level as the 0.47 Ohm jack? Do a quick A-B comparison. In my case it drives the HE-400 just as hard out of either, though it does sound different due to damping factor differences (especially with higher Z phones like the HD 650).

If that is not an amplified output, then I am confused about what that term means.  It sounds like the definition of an amplified output to me.

Who said this you asked.

All of the people, including LH Labs, that say that the 47 Ohm jack can be used for higher Z headphones are essentially saying that it is an amplified output. You can find many reviews and even descriptions directly from LH Labs that make this statement.

Here is one:

http://www.audiostream.com/content/lh-labs-geek-out-1000-dacheadphone-amplifier

There's on-board volume controls and little LEDs that indicate what sample rate you're currently playing and two 3.5mm analog outputs, 47 Ohm for the line out and higher impedance headphones and 0.47 Ohms for lower impedance headphones.

Or this from the GO Kickstarter page:

Problem - You want to share your music with a friend.  So, you hand him or her one earbud, and you listen to the other.  That sucks!

• It's a shareulator.  GEEK has two headphone jacks!

Of course, an amplified headphone output can act as a psuedo line output to drive another amp, as long as it can swing the required voltage into the HiZ load, but it is still an amplified output. This means using it for this purpose is "double amping"!

If you are interested take a look at this article:
http://www.audiostream.com/content/lh-labs-geek-out-1000-dacheadphone-amplifier

While the GO 47 Ohm output can be used to drive an amp, it is not anything even close to a true line output.

I figured the volume attenuation was on the DAC level. You can still produce sound from a DAC and still have it attenuated digitally. You can try this with most devices that have a line out connection. Often times the line out is loud though because they're often set to produce the maximum output voltage, or maximum volume if you're using a headphone out port. I believe the Objective DAC does this. The ODAC delivers 2 VRMS to the next item in the audio chain if the digital volume is maximised.

Line out connections usually have a high output impedance because it requires minimal current transfer to the amplifier, or whatever thing is next in the audio chain. It just so happens that high-impedance headphones are also voltage-driven as opposed to current-driven like lower impedance earphones (hence why headphones like the HD800 are often fine with being driven with amps of high output impedance). I think the voltage dependence has a more audible effect than the damping factor. One typically shouldn't drive lower impedance headphones from a high impedance source because the circuit might be shorted due to a high current being required.

 

[BA_D_R]

I got DragonFly 1.2 should I buy Geek Out 450, is it really better than DragonFly 1.2
My headphone is Ultrasone Signature DJ (32 ohm)

 

[maestr01]

Just got my Geek Out 1000. I am pairing it with my AKG Q701s and I just love the SQ on this little device. It makes my AKG Q701 sound like a whole new headphone. The bass is much improved and yet sounds punchy. I can't wait for the pulse and wave to arrive now.
 
The sound definitely improves when it has a little bit of time to warm up. I leave it on for about 30 minutes and the device is sufficiently ready for better and warmer sound.

 

[Mannytorres]

Hey I love my GO 1000, throw some DSD on it and about a a half hour to settle in, It will sound awesome,
 
 
Manny/ Light Harmonic

 

[Gilly87]

any word on whether issues with Windows volume have been addressed by LH?

 

[Gilly87]

Ok, good to know. I'm ready to buy as soon as you guys can give me a 100% guarantee that I'm not gonna blow my IEMs
 
Quote:

  Hey Gilly,
 
Yeah we are getting pretty close here, working on firmware and an enclosure, this should be pretty fun.

 

[Gilly87]

Still curious if anyone has tried this badboy with the T90s...

 

[longbowbbs]

Geek Out 1000 with Sennheiser HD650's and Toxic Cable Silver Poison's via MBP and Amarra 3.02