Singxer SA-1 Review (Balanced Headphone Amp)

[gvl]

Yeah, I've gone through several good measuring ESS DACs such as the Khadas Tone Board, Topping D10s DX7 and DX7 Pro, Sabaj D5, for various reasons, and I can say that they are basically sound the same, as it should be. I suspect SU8 sounds the same too.

 

[gonzoznog]

Mine is a version 2 SU-8, so a bit better than the early ones. The better DAC's since then have a bit better measurements, a few more features, and a few put out a higher voltage (which I have read a few folk saying is a good thing for the SA-1). As you suggest, however, that may well not be worth the upgrade.

I think it's worth it to upgrade from the SU-8. I previously had one. It was just aight... I think the D70s is a clear step up if you want Delta-Sigma or a Schiit Bifrost or Denafrips ARES II if you wanted to go R2R.
Just my $0.02.

 

[bloodshoteyed]

i wonder how many products with CE stickers were actually certified so far (not to bash China specifically, but you know what i mean...) ...

oh...

https://support.ce-check.eu/hc/en-u...-Real-CE-Mark-From-A-Fake-Chinese-Export-Mark

 

[Kype_Kypeee]

Great review! Thanks

 

[w1000i]

@amirm Dear can you masure this amp with adding jumpers to bypass the caps ? It's been done and people report improvement. Can you investigate that if possible

 

[Veri]

@amirm Dear can you masure this amp with adding jumpers to bypass the caps ? It's been done and people report improvement.

Singxer posted earlier in this thread they will remove this jumper from future amps, since a DAC with considerable DC offset combined with cap bypass / DC coupling, could damage upstream gear. The only effect that could show up would be below 20Hz and it would be tiny. Those 'improvements' people write about are surely in their head lol.

 

[Metalshock]

Hi all,
i have the SA-1 hooked up with a Topping E30 going in optical from the pc.
when using as a PRE amp for powerd speakers, i get a pop when switching from OFF to PRE.

Is it just mine or has anyone else the same behaviour?


EDIT: Going XLR from SA-1 To speaker

 

[w1000i]

Singxer posted earlier in this thread they will remove this jumper from future amps, since a DAC with considerable DC offset combined with cap bypass / DC coupling, could damage upstream gear. The only effect that could show up would be below 20Hz and it would be tiny. Those 'improvements' people write about are surely in their head lol.

Any chance that will affect the load impedance and distortion ?

 

[w1000i]

Singxer posted earlier in this thread they will remove this jumper from future amps, since a DAC with considerable DC offset combined with cap bypass / DC coupling, could damage upstream gear. The only effect that could show up would be below 20Hz and it would be tiny. Those 'improvements' people write about are surely in their head lol.

BTW, I did quick swap with and without many times , and couldn't tell a clear different.

 

[Highvolt60]

Singxer posted earlier in this thread they will remove this jumper from future amps, since a DAC with considerable DC offset combined with cap bypass / DC coupling, could damage upstream gear. The only effect that could show up would be below 20Hz and it would be tiny. Those 'improvements' people write about are surely in their head lol.

The effects of the 330uF Nichicon bipolar electrolytic caps will be heard across the frequency band.
In this design, they are also bypassed with some cheapo 1uF film caps but its always best to never have any AC coupling caps in the circuit !
My Oppo source already has output coupling caps so removing the secondary caps in the SA-1 was a no brainer.
My previous amp was DC coupled by design so I'm always aware of the issue (don't want constant DC at the headphones).
if your source has more than +/- 5mv or so then keep the caps in the circuit (especially if you use high gain).
I only noticed a small difference but did not do a direct A/B comparison (Balanced in/out & low gain setting with volume at about 9:00).
I also soldered the pins together since I would never use those cheap PC jumpers etc.
One last thing is that the coupling caps are on the wiper side of the 10k volume pot Vs the input ?
The caps may have more influence on the sound if you have the volume pot generally set to a lower level.

 

[JohnYang1997]

The effects of the 330uF Nichicon bipolar electrolytic caps will be heard across the frequency band.
In this design, they are also bypassed with some cheapo 1uF film caps but its always best to never have any AC coupling caps in the circuit !
My Oppo source already has output coupling caps so removing the secondary caps in the SA-1 was a no brainer.
My previous amp was DC coupled by design so I'm always aware of the issue (don't want constant DC at the headphones).
if your source has more than +/- 5mv or so then keep the caps in the circuit (especially if you use high gain).
I only noticed a small difference but did not do a direct A/B comparison (Balanced in/out & low gain setting with volume at about 9:00).
I also soldered the pins together since I would never use those cheap PC jumpers etc.
One last thing is that the coupling caps are on the wiper side of the 10k volume pot Vs the input ?
The caps may have more influence on the sound if you have the volume pot generally set to a lower level.

High value electrolytic caps has zero effect on sound quality. The distortion of the RC is lower than 0.00003% across 20-20khz. Are you sure you can hear this level of distortion?

 

[Highvolt60]

High value electrolytic caps has zero effect on sound quality. The distortion of the RC is lower than 0.00003% across 20-20khz. Are you sure you can hear this level of distortion?

Believe what you want however the characteristics of electrolytic caps ESR & ESL (Equivalent Series Resistance & Inductance) varies several orders of magnitude from different manufacturers and types of caps not to mention over the audio frequency range.
Distortion has nothing to do with it as no human can detect even .1% THD.
Been measuring caps for over 35 years and still don't understand why things sound the way they do ?

Perhaps if someone is NOT an engineering professional, they should not be messing with the innards of this amp anyway !
BTW: Doing so will void your warranty...

 

[JohnYang1997]

Believe what you want however the characteristics of electrolytic caps ESR & ESL (Equivalent Series Resistance & Inductance) varies several orders of magnitude from different manufacturers and types of caps not to mention over the audio frequency range.
Distortion has nothing to do with it as no human can detect even .1% THD.
Been measuring caps for over 35 years and still don't understand why things sound the way they do ?

Perhaps if someone is NOT an engineering professional, they should not be messing with the innards of this amp anyway !
BTW: Doing so will void your warranty...

What does then? You can perform null test and prove residuals are way below anything human can detect. And no audible difference there is when engineered properly.

 

[Veri]

Got my Singxer SA-1 in. Serial no is pretty low though, I think I got a returned unit at full price but eh, all looks new/fine so I guess that's okay. Sounds good and could't get any noise or hum issues from any of my SE/BAL input/output combinations so that's good.

I find the knob counter-intuitive though. I'm used to linear pots. On the SA-1 the gain increment is very slow throughout most of the range and then suddenly extremely rapid by the very end.

 

[Metalshock]

Got my Singxer SA-1 in. Serial no is pretty low though, I think I got a returned unit at full price but eh, all looks new/fine so I guess that's okay. Sounds good and could't get any noise or hum issues from any of my SE/BAL input/output combinations so that's good.

I find the knob counter-intuitive though. I'm used to linear pots. On the SA-1 the gain increment is very slow throughout most of the range and then suddenly extremely rapid by the very end.

I also have no hum or noise issue on any output. The only thing i noticed is that i get a popping sound when switching on. Do you have the same behaviour?

 

[Veri]

I also have no hum or noise issue on any output. The only thing i noticed is that i get a popping sound when switching on. Do you have the same behaviour?

Are you using pre-outs? I don't get the pop from my little testing so far, no.

 

[raif71]

I also have no hum or noise issue on any output. The only thing i noticed is that i get a popping sound when switching on. Do you have the same behaviour?

I have no popping sound switching from pre to hp or vice-versa...using gustard x16 as dac via xlr and audio-gd r2r11 via rca

 

[Metalshock]

I have no popping sound switching from pre to hp or vice-versa...using gustard x16 as dac via xlr and audio-gd r2r11 via rca

From Pre to HP or vice-versa i have no popping aswell. Only from OFF to Pre, as i mentioned.

 

[raif71]

From Pre to HP or vice-versa i have no popping aswell. Only from OFF to Pre, as i mentioned.

I would say this too is non popping as well.

 

[Metalshock]

Are you using pre-outs? I don't get the pop from my little testing so far, no.

yes, Pre outs