Singxer SA-1 Review (Balanced Headphone Amp)

[MakeMineVinyl]

View attachment 129598

That's quite a clean layout, and the parts look high quality.

 

[amirm]

I was thinking the usual XLR in, 6.35mm out for almost all the tests. They omitted the half branch of the XLR when using 6.35mm out, similar to Magnius essentially. And when loaded the performance also degrades a lot with 6.35mm out.

For balanced in and out amps, I like to emphasize that configuration. On that measurement you showed, I didn't get anything like that. Distortion was vanishingly low -- much lower than what I showed for RCA in -- and only the mains hum went up as he has. And I reported in the review.

 

[TheTalbotHound]

someone from another site took off the heatsink to get a look at what's underneath.

http://www.erji.net/data/attachment/forum/202012/30/140838mi4zzcvzc80nvppz.jpg

 

[Celty]

I had been keeping my eye on the SA-1 for awhile based on the other reviews I had come across, but I was holding off hoping Amir would review it. Now I am sorely tempted to replace my Monolith 887 with this Singxer.

 

[lizhuoyin]

It was a pathetically bad attempt to make a joke. If they sourced some parts from other than their native China, then maybe some came from the USA. But the USA makes almost no consumer electronic parts. We buy them from somewhere other than here. Its a sore spot for some people that 'nothing' is totally made in the US. Like Philco televisions in the 1950s in which every screw and capacitor was made in the USA.

See the logic? I'll draw you a diagram is you wish.

As I know, TI ICs and Vishay transistor s are made in USA.

 

[PeteL]

It was a pathetically bad attempt to make a joke. If they sourced some parts from other than their native China, then maybe some came from the USA. But the USA makes almost no consumer electronic parts. We buy them from somewhere other than here. Its a sore spot for some people that 'nothing' is totally made in the US. Like Philco televisions in the 1950s in which every screw and capacitor was made in the USA.

See the logic? I'll draw you a diagram is you wish.

Ever heard of Silicon Valley?

 

[Billy Budapest]

It was a pathetically bad attempt to make a joke. If they sourced some parts from other than their native China, then maybe some came from the USA. But the USA makes almost no consumer electronic parts. We buy them from somewhere other than here. Its a sore spot for some people that 'nothing' is totally made in the US. Like Philco televisions in the 1950s in which every screw and capacitor was made in the USA.

See the logic? I'll draw you a diagram is you wish.

Actually, many resistors, capacitors, etc., are still made in the USA.

 

[Doodski]

Actually, many resistors, capacitors, etc., are still made in the USA.

I was reading some stuff a few months ago and it pointed toward the East Euro area producing some components that formerly came from the USA.

 

[MakeMineVinyl]

Actually, many resistors, capacitors, etc., are still made in the USA.

Of course some component parts are still made in the US, but the majority of components used in typical price sensitive consumer electronics are not made here.

 

[MakeMineVinyl]

Ever heard of Silicon Valley?

Sure, but what substantial consumer electronics manufacturing is going on there?

 

[Matias]

That channel imbalance though....

 

[JohnYang1997]

WOW, amazing results for class A amp.

Not class A unfortunately.

 

[amirm]

I should note something I forgot. The volume control works gradually and then sharply increases volume toward the end. Seems like it has a non-standard taper. This may explain why it shows anomalies at max level and not min.

 

[Cahudson42]

Add a 110db DAC and 10-band PEQ, and maybe it's worth $600..

 

[H-713]

I should note something I forgot. The volume control works gradually and then sharply increases volume toward the end. Seems like it has a non-standard taper. This may explain why it shows anomalies at max level and not min.

Sometimes this can happen if they're using a regular log pot with significant loading.


I must say though, it looks very much like a discrete implementation. Probably a standard class AB power amplifier design, though obviously well executed.

One thing I have to ask, why the hell did we need to have two different balanced headphone connectors? Having three output connectors on the front of an amp is ridiculous.

I also really don't see a need to have differential outputs on a headphone amp where they could use whatever voltage rails they want. They could run it on +/- 24V, have all the headroom in the world, and any additional costs that incurs (not much) would be more than offset by not needing a 4-gang pot (which is probably the most expensive part of the whole amp). You could also eliminate two power amplifier sections, save PCB space and a significant BOM cost.

 

[H-713]

I'm also not so sure about those toggle switches. In my experience, toggle switches (unless they have gold-plated contacts, which isn't very common) are a bit of a sore spot. Wait five or ten years and there's a good chance you won't be so happy about them.

IMO, for line (and especially mic-level) signal switching, gold-plated contacts are a must. Relays are another solution, but add quite a bit of cost.

 

[PeteL]

Sure, but what substantial consumer electronics manufacturing is going on there?

The list would be long, butt small compagnies like Intel and Qualcomm for a start

 

[MakeMineVinyl]

The list would be long, butt small compagnies like Intel and Qualcomm for a start

I specified consumer electronics manufacturing, i.e. finished goods - that was the context of my original post regarding this, and specifically relevant to this thread, audio consumer electronics. The list suddenly gets pretty short in that case.

 

[PeteL]

I specified consumer electronics manufacturing, i.e. finished goods - that was the context of my original post regarding this., and specifically relevant to this thread, audio consumer electronics.

First, apologies for sounding snarky, you don't necessarily know. Now quote: "But the USA makes almost no consumer electronic parts", WAS the context, you also said: If this was USA, it would means that it containt PARTS that are from abroad.

Just pointing out that USA is, by a good margin the largest semiconductors components manufacturer in the world. Sure, no debate that for everything else, assembly, mechanical parts, Plastic molding, etc, etc, etc, Asia is far far ahead, but it is not the point you first made!

 

[JohnYang1997]

Sometimes this can happen if they're using a regular log pot with significant loading.


I must say though, it looks very much like a discrete implementation. Probably a standard class AB power amplifier design, though obviously well executed.

One thing I have to ask, why the hell did we need to have two different balanced headphone connectors? Having three output connectors on the front of an amp is ridiculous.

I also really don't see a need to have differential outputs on a headphone amp where they could use whatever voltage rails they want. They could run it on +/- 24V, have all the headroom in the world, and any additional costs that incurs (not much) would be more than offset by not needing a 4-gang pot (which is probably the most expensive part of the whole amp). You could also eliminate two power amplifier sections, save PCB space and a significant BOM cost.

1, People need different output jacks. Simple as that. It's inconsistent if you need adapters to use headphones.
2, Running on +-24V won't give you all the headroom. A30pro does it and although it's a great solution it doesn't have a chance in output power comparing to +-15V and balanced.
3, They clearly don't have the capability to design low distortion single ended output amplifier. When loaded the single ended output has much much higher distortion.