[Ichos]

Is it possible that the DAC wasn't connected balanced to the amp section, but the discrete amp section was balanced?

Yes it converts the single ended stereo output to a balanced signal to be amplified.
It is a common procedure for a lot of designers.
For example the famous Violectric V280/281 works this way.
It converts the stereo input to balanced output.
It is not a fully balanced design just a balanced amplifier.

 

[Guy Fawkes]

Everything you stated is wrong. Pretty sure any Ess modern dac, and the same goes for akm and cirrus logic, has differential output by default. Here's the data sheet for es9038q2m, as you can see pins 2 and 3, 8 and 9 are the differential output of the dac. Ech stereo dac channel has its own differential outputs.

This gives a balanced output, but not a fully balanced output


.

 

[lantian]

This gives a balanced output, but not a fully balanced output


.

Care to explain? A differential signal is what we call balanced, there is no balancedsignal but "true" not balanced output. If a dac chip has duffentual outputs then it is that differential output as in hot and cold signals. Everything we use balanced/differential amplifiers use this exact method. Only way for it not to be true diffential signal is if and op Amp would be used to turn the single ended one to differential. This is not the case here, nor is it the case with any moder audio device. Because most if not all dacs output differential signal and if you want to have the best sound and cheapest build you will use this differential signal as is. Therefore it all is balanced, for consumer and pro audio there is no difference between the terms differential and balanced signal. It's the same and if it's balanced then its is balanced.
It's true that older dacs and. The r2r ones don't usually come with differential outputs, so one needs two of them to make a differential dac, not the case for st least a decade now.
It's also true that some amplifiers might only have differential input and after that covert it back to single ended signal for simplicity and cost reasons, some covert it right before and right after the volume control, these designers could be called semi balanced/differential. But everything else is either balanced or is not, especially dac chips.

 

[ishmaelk]

First impressions: there isn't much difference in quality between balanced and single ended output, apart, obviously, from the power. That's something good.
The 6XX sounds fantastic in balanced with the X1S GT. It adds more depth and more air in the highs. The added depth is welcome, specially because the X1S GT seems to be quite forward in its sound.
With the Avantone Planar, though, I think I have a problem. There's more than enough power to go deaf, but there's a loss of resolution in the lower frequencies. And this is a headphone with amazing bass texture and detail. There's just not enough power to show that in the Avantone Planars.
I love the looks and the sturdy build.
I'll give it more time in the next couple of days and compare it with the only thing I have now at home: ifi XDSD and Modi 3+ Magni 3+ stack.

 

[verde57]

• Frequency response: 30 - 30,000 Hz

• Avantone Planar​

 

[linknet]

Hi,
Some impressions...
It's been a month that i got it and i'm very happy. Streaming Qobuz through my smartphone and UAPP bit-perfect. I use it 6.35mm with my Sundara and ATH-R70X, volume around 9-10 o'clock in a quiet room. Tried 4.4mm but too much power (for me) and quite no room to decrease the volume as it's already near the minimum (also sounds a bit more aggressive with less harmony to my ears).
Tried the 4 filters. Prefer the second one.
The sound is very musical and enjoyable. More than my AK SR25 who has that reputation.
I will only add some low-medium-high gain possibility.
It was a blind buy but absolutely no regret

 

[ishmaelk]

Hi,
Some impressions...
It's been a month that i got it and i'm very happy. Streaming Qobuz through my smartphone and UAPP bit-perfect. I use it 6.35mm with my Sundara and ATH-R70X, volume around 9-10 o'clock in a quiet room. Tried 4.4mm but too much power (for me) and quite no room to decrease the volume as it's already near the minimum (also sounds a bit more aggressive with less harmony to my ears).
Tried the 4 filters. Prefer the second one.
The sound is very musical and enjoyable. More than my AK SR25 who has that reputation.
I will only add some low-medium-high gain possibility.
It was a blind buy but absolutely no regret

Hi.
I have been trying the X1S GT with my R70X, too.
I have the impression that, running them unbalanced, they sound darker than with Magni 3+.
I don't know why that would be. Usually, when an amp doesn't have enough power, sound is thinner, lean, not thicker.
Side to side, with the 6XX balanced and the R70X unbalanced, the 6XX is the brighter of the two.

 

[verde57]

analog volume around 9-10 o'clock is never good for sound
it should be over 12 o'clock for normal listening levels to get full freq and dynamics.

 

[linknet]

analog volume around 9-10 o'clock is never good for sound
it should be over 12 o'clock for normal listening levels to get full freq and dynamics.

According to which law ???
And so how is the volume around 9-10 o'clock on the X1s GT much better (to my ears) than at 90 (max.150) on my SR25 ???

 

[verde57]

Probably Ohm's Laws. someone with electronics knowledge can explain better than me.
you can test this yourself with the GT and Jriver player.
Jriver is capable of controlling the volume digitally without bit loss, so you decrease the volume level on JRiver and increase accordingly the volume level on the GT.

You should be able to hear a big difference in sound(fullness, dynamics, etc.)

 

[linknet]

Probably Ohm's Laws. someone with electronics knowledge can explain better than me.
you can test this yourself with the GT and Jriver player.
Jriver is capable of controlling the volume digitally without bit loss, so you decrease the volume level on JRiver and increase accordingly the volume level on the GT.

You should be able to hear a big difference in sound(fullness, dynamics, etc.)

Thanks for your reply.
I have my comfort level of volume and can not go higher as my ears are sensitive...
When Aune talks about "uncompressed dynamics" does it not mean that going louder just make it louder with no change in sound ???

 

[ishmaelk]

Hi.
After a few days comparing the X1S GT with the (Modi + Magni) 3+ stack, I've come to two conclusions: the DAC in the X1S GT is noticeably better than the Modi 3+ and the amp section is slightly smoother and better for the 6XX thanks to the balanced output. In SE, 6XX feels less congested in the Magni 3+ thanks to the extra power, or that's my impression. When I use the 4.4 mm output, the 6XX opens up more and there's a depth you can't get with the Magni 3+.
Not that the X1S GT nor the Magni 3+ can give much depth, to be honest. But you don't really expect it at this price point.
So far, really good.

 

[AuneAudio]

We noticed some discussions about balanced headphone amplifier. Actually “balanced amplifier” has many names, like BTL AMP (Bridge Tied Load amplifier), differential amplifier, etc. Their essence is the same: to drive load with differential signals.

Examples:

But “fully balanced amp” refers to a design of discrete-component amplifier circuit. Like this:

The advantage of the amp with that kind of circuit is that the slew rate is more symmetrical. But now there are other methods to realize that as today’s transistors have progressed a lot in performance.

The amp of the X1s GT uses ultra-low-noise JEFT input, two order voltage amplification stage. The open-loop gain is high. The overall performance is ideal. Below is the X1s GT balanced headphone amp driving 600Ω with full level:

INPUT@1KHZ 0dBFS VOL @max


Second and third distortion are both lower than -112dB


Let’s compare dynamic range between input signal level and volume of the headphone amplifier:

INPUT@1KHZ -60dBFS VOL @max


Unweighting dynamic range: 118dB

INPUT@1KHZ 0dBFS VOL @-60dBFS

Unweighting dynamic range: 125dB


Therefore, for volume adjustment, to adjust the potentiometer of the X1s GT is the best way. It can achieve larger dynamics at an usual volume. Generally, it’s recommended that the computer volume is set to max. Of course to some IEMs the volume has to be very low. Then we can also adjust the player’s digital volume. The range of -1dB to -10dB is fine. It won’t cause much loss.

As for DAC’s output, nowadays, almost all DAC chips use differential output, which is to improve CMRR performance of signals.

 

[verde57]

 

[verde57]

sure noticed the 10k low resistance potentiometer