[Thetaburn]

I've tried the 4.4 output and it sounded different in a bad way than the XLR.

What is the difference?

 

[Thetaburn]

Recently purchased a used Burson Soloist 3x.
A/ B ING that against the Sa1. Initial impression is that the Sa1 has tremendous value.

Ease of use goes to the SA1.
Toogle switches is the way to go.

Technically the soloist is better in term of depth.
The Soloist is quirky, you have to power the unit with nothing plugged in. If headphone ares are plugged in, there is a moderately loud pop sound. Same for powering down.

On the Soloist, sound signature is very dynamic, whereas singxer is soft and relaxed. That's personal preference.

Still not sure which one to keep, as the Soloist is double the price of a SA1.

 

[lightoflight]

I tried both and could not detect a sonic difference.

Because we're both using different equipment so results will vary. In my case, I will never use the 4.4.

 

[lightoflight]

What is the difference?

My SA-1 is my summertime amp, so it's not plugged in right now. I'm going by memory here; 4.4 was noticeably lower in resolution.

 

[Alex May]

I've tried the 4.4 output and it sounded different in a bad way than the XLR.

It means that your 4.4 cable sucked in a bad way in terms of low quality materials used or some fault in assembly. There is no other explanation because the SA-1 circuitry connecting to the XLR and 4.4 is absolutely the same.

 

[lightoflight]

It means that your 4.4 cable sucked in a bad way in terms of low quality materials used or some fault in assembly. There is no other explanation because the SA-1 circuitry connecting to the XLR and 4.4 is absolutely the same.

I don't know, maybe. I used the same headphone HE1000se, same silver plated 7N OCC cable terminated in 4.4 and a ddHifi 4.4 to 4 pin XLR adapter. The equipment shown here.

 

[Alex May]

@lightoflight Silver plated technology is a bad choice in the first place, especially for high resolving transducers. It might not be noticeable for the majority of the headphones, especially dynamic. But when using silver plated cables as interconnects between DACs and amplifiers, or for high resolving planars, you can sometimes hear the difference. Since the signal travels primarily along the surface of the conductor, coating it with a metal of different conductivity, combined with high capacitance, degrades the signal. Of course, it depends on many factors that lead to difference in conductivity, capacitance, interference and filtering caused by plating. I clearly see that you have a low quality cable in your photograph that's not commensurate with the quality of your headphones. I have no idea why there might be an improvement using the XLR adapter. Maybe it rectifies the filtering effect in some way. Maybe it has some influence on capacitance, I don't know.

Regardless of the explanation, the fact remains the same: the circuitry that feeds the signal to the 4.4 and XLR in the SA-1 is the same. If you hear a difference, it is caused by external factors and nothing else. The problem here is to isolate those external factors. Anyway, it has nothing to do with the amplifier itself.

 

[hundreth]

Because we're both using different equipment so results will vary. In my case, I will never use the 4.4.

Thanks for the response. Seems odd that they would sound different but it is possible. Hopefully others chime in.

 

[Thetaburn]

@lightoflight Silver plated technology is a bad choice in the first place, especially for high resolving transducers. It might not be noticeable for the majority of the headphones, especially dynamic. But when using silver plated cables as interconnects between DACs and amplifiers, or for high resolving planars, you can sometimes hear the difference. Since the signal travels primarily along the surface of the conductor, coating it with a metal of different conductivity, combined with high capacitance, degrades the signal. Of course, it depends on many factors that lead to difference in conductivity, capacitance, interference and filtering caused by plating. I clearly see that you have a low quality cable in your photograph that's not commensurate with the quality of your headphones. I have no idea why there might be an improvement using the XLR adapter. Maybe it rectifies the filtering effect in some way. Maybe it has some influence on capacitance, I don't know.

Regardless of the explanation, the fact remains the same: the circuitry that feeds the signal to the 4.4 and XLR in the SA-1 is the same. If you hear a difference, it is caused by external factors and nothing else. The problem here is to isolate those external factors. Anyway, it has nothing to do with the amplifier itself.

The 3 stock cables included with the Hekv2 are silver plated.......
Sound signature is different from pure OCC copper vs silver plated vs pure silver.
Didn't know, silver plated cable could degrade signal though.

 

[Alex May]

The 3 stock cables included with the Hekv2 are silver plated.......

The stock cables from Hifiman are notoriously the worst among all the headphone manufacturers. Even with their highest top tier headphones. Therefore, all the Hifiman users always have to buy third party cables. At least those I heard of, including myself. Audiophile Ninja, Hart Audio Cables and Periapt are the most popular budget options. Tripowin GranVia is an honorable mention as a very budget but still quality option. And then there are Arctic Cables and Forza AudioWorks.

Sound signature is different from pure OCC copper vs silver plated vs pure silver.

Absolutely.

 

[Lolito2]

It sounds so much better via balanced output than single ended...

kanker lol

 

[hundreth]

Can anyone explain something related to this amp and gain levels?

On high gain it's at +11db. Some reviewers and normal listeners have noted that they weren't able to get enough drive out of this amp because it's only +11db, where standard amps are between +16db and +30db gain.

If that's the case, then what is the relationship between this gain level, volume, and measured power? If we're measuring 6+ watts out of this unit, why are there reports that it can't drive certain headphones and how is that related to this gain level?

 

[Glokta]

The measured / declared power is already with the gain switches to max, at a certain input voltage, usually 4V using the balanced input. That gain value that you see (11, 16dB....etc) is not added to the power output shown on paper.
What you need to look at an amp is if it distorts at the said gain level (this one doesn't) and what are you going to feed it with because if you're going RCA 2V route then obviously you're not going to reach peak power.
I've no idea what other user reported and what it can't drive, from what I've seen a lot don't know or understand that it has a logarithmic volume pot and they get scared when it reaches 3 o'clock and the volume is lower than their other less powerful amp. What I can tell you is that fed by a 5V output DAC it can drive HE6SE v2 in normal gain mode without even reaching max volume on the pot.

 

[hundreth]

The measured / declared power is already with the gain switches to max, at a certain input voltage, usually 4V using the balanced input. That gain value that you see (11, 16dB....etc) is not added to the power output shown on paper.
What you need to look at an amp is if it distorts at the said gain level (this one doesn't) and what are you going to feed it with because if you're going RCA 2V route then obviously you're not going to reach peak power.
I've no idea what other user reported and what it can't drive, from what I've seen a lot don't know or understand that it has a logarithmic volume pot and they get scared when it reaches 3 o'clock and the volume is lower than their other less powerful amp. What I can tell you is that fed by a 5V output DAC it can drive HE6SE v2 in normal gain mode without even reaching max volume on the pot.

Thanks for the explanation. Very helpful.

I was looking at this review here:
https://soundnews.net/amplifiers/headphone-amps/singxer-sa-1-class-a-headphone-amplifier-review/

Where he says:
"It offers some 6480 mW in 32Ω and 380mW in 600Ω on its balanced outputs and I’m not sure how much power is being offered on its regular jack, since there aren’t any official specifications. Its low gain position uses the unity gain (0 dB) and that is the best gain setting for IEMs and sensitive headphones. Its high-gain adds 11 dB of gain and that could be a slight issue with hard to drive headphones, as usually high-gain sits at around 16 to 30 dB of gain, sometimes even higher, will see about that very soon."

and...

"I’ve observed that with the Audiobyte HydraVox that offers a lower voltage of 3.8 V on its XLR output, the high-gain wasn’t enough with some particular headphones. For example, Audeze LCD-4 were almost maxed out, leaving little to no headroom for better mastered music. In my humble opinion, Singxer should go with a higher gain, 16, 20 or 25 dB would be perfect with much harder loads. The good news is that when I’ve switched to a Gustard X26 PRO that outputs a much higher 5V on its XLR, the volume plunged higher and SA-1 was now fully driving the LCD-4 with flying colors, leaving plenty of headroom for higher dynamics. If you find it a little overwhelming at first, I recommend trying a source that can output a higher voltage to the industry standard 4V and you’ll be squeezing more power from it."

"
There is one thing that I dislike the most about it: its gain settings, more exactly its high gain that offers an increase of only 11 dB (a 3.8-time magnification). Usually, desktop headphone amplifiers offer a higher gain, somewhere between 16 and 30 dB on their high-gain setting. Here are just several examples: Headamp goes with a gain of ~21 dB on their GSX MKII, Flux Lab Acoustics goes with a gain of 25 dB on their FA-10, Audio-GD goes higher to 31 dB with HE-9, so on and so forth. In simpler words, SA-1 can struggle with several hard to drive headphones as Audeze LCD-4, even Hifiman Arya can pose a small problem. You can solve that issue by adding gain from your source. If your DAC outputs 4V or less on its XLR output, then SA-1 will be almost maxed out with headphones like Audeze LCD-4, but if your DAC provides a higher voltage like 5V (Topping D70S, Gustard X26 PRO) or 6V (Gustard A22), then that will work as a gain increase and SA-1 will offer you back more power, driving harder loads much easier. When I’ve used it with the Audiobyte Hydravox that outputs 3.8V, Singxer struggled a bit and it worked much better with DACs that offered a higher voltage."

So I'm guessing he just didn't understand the logarithmic pot? If the measured power is at 4V, we shouldn't need a special DAC to pair with this amp.

 

[Glokta]

I don't remember LCD-4 being harder to drive than HE6SE...
With 630mw at 300Ohm, if you feed it 4V you should be alright for almost everything you throw at it.
As I said above, the hardest to drive headphone that I own is the HE6SE v2 and SA-1 delivers without a problem.