Sabaj A10h Review (Headphone Amplifier)

[Jimbob54]

Everything Mola Mola is over hyped and nothing more then seriously overpriced pieces of garbage that even roaches don't want to get to close to. That Mola Mola even can excist is a fundamental failure of the human race.

And they cant even put the headphone jack in the right place

 

[Lupin]

And they cant even put the headphone jack in the right place

It works for them.
People who are willing and stupid enough to pay that much for a piece of utter crap don't have the brain capacity to even realize the headphone jack is in a completely illogical place.

 

[dmac6419]

Time to play,this thing is crazy good with the Ibasso DX300 original amp card LO

 

[tomchr]

Be aware though, prof @WolfX-700 measurement shows some power frequency interference: https://www.l7audiolab.com/f/sabaj-a10h/

You can see the same in Amir's measurements. The FFT on the AP dashboard shows plenty of mains hash and resulting IMD products. Given it's $120 I wouldn't complain. I would be disappointed if I'd spent $1200 on it.

@amirm - Have you had a chance to crack it open? I'm curious about which relays they used. Or whether they used a volume control chip and a single relay for the sound effect. Seriously. Good small-signal relays are expensive. At the production volumes I'm normally looking at I can't even buy the relays for $120.

Tom

 

[Curupira]

I did not. In this class of product it always has the same performance as the headphone out.

*Laughs in K5 Pro*

 

[tomchr]

Never mind: https://www.audiosciencereview.com/...-review-headphone-amplifier.25699/post-876937

Looks like good relays. Omron G6K-2F-Y. Eight of them in the attenuator. Digikey pricing (USD) below.

Tom

 

[David_M]

With such good SINAD specs of -118dB for the unbalanced outputs, it would have hit -121dB or more, if it had balanced outputs, making it an oddity of sorts. Excellent specs and still super low price.

 

[Tatteredmidnight]

Everything Mola Mola is over hyped and nothing more then seriously overpriced pieces of garbage that even roaches don't want to get to close to. That Mola Mola even can excist is a fundamental failure of the human race.

Who hurt you? The Mola Mola is undeniably expensive, but it also measured impeccable. With all the examples of overpriced gear that perform like garbage, why are you so angry at one that is measurably excellent?

 

[Pdxwayne]

Got mine. So far it does not like 1khz tone when using H2 volume level, near -15db or so. It starts to output distorted sound.

Here is REW RTA for 1khz, when playback at -11db with H2 volume level:

 

[tomchr]

H2 volume level?

Are you sure it isn't clipping? The FFT looks a lot like it's running at the onset of clipping.

Tom

 

[Pdxwayne]

H2 volume level?

Are you sure it isn't clipping? The FFT looks a lot like it's running at the onset of clipping.

Tom

I wonder why it would clip....Amir said it can take more than 2V and can output more than that too. At about -16db volume level and I start seeing this patterns. My ADC not yet reach clipping level.

 

[tomchr]

What happens if you lower the output level from the sound card?

I can see a couple of possibilities why it may clip: Sound card output is clipping; sound card input is being overdriven; amp is clipping.

I would be surprised if the amp is causing trouble, though depending on how they designed the circuit, it could. There are a couple of different relay attenuator topologies and at least one of them has variable input impedance. That could end up loading the buffer (or your sound card output if the amp is unbuffered to the volume control) with too heavy a load, thereby degrading THD. If that's the case, you'll find that the amp will distort around certain volume settings but not away from those settings.

Tom

 

[Pdxwayne]

What happens if you lower the output level from the sound card?

I can see a couple of possibilities why it may clip: Sound card output is clipping; sound card input is being overdriven; amp is clipping.

I would be surprised if the amp is causing trouble, though depending on how they designed the circuit, it could. There are a couple of different relay attenuator topologies and at least one of them has variable input impedance. That could end up loading the buffer (or your sound card output if the amp is unbuffered to the volume control) with too heavy a load, thereby degrading THD. If that's the case, you'll find that the amp will distort around certain volume settings but not away from those settings.

Tom

If I set REW tones generator level down to -10dBFS, then I can use max volume without clipping.

 

[tomchr]

And with -10dBFS, does it still clip at -15 dB or is it clean all the way from, say -40 dB to 0 dB?

Tom

 

[Pdxwayne]

And with -10dBFS, does it still clip at -15 dB or is it clean all the way from, say -40 dB to 0 dB?

Tom

It is clean all the way to 0db.

 

[tomchr]

Sweet! Sounds like the ADC in the sound card was clipping then. Thanks for following up.

Tom

 

[Pdxwayne]

The A10H's preouts look ok as compared to RCA out from my Gustard X16.

Here is Gustard X16's RCA to my ADC for REW 1KHz RTA:

Here is X16 RCA to A10H, A10H preout to ADC, for REW 1KHz RTA:

 

[solderdude]

You are looking at the distortion of the ADC.
Both the Gustard and a10h perform MUCH better than your ADC.

When you really want to measure equipment you should use an ADC that exceeds the 'worst' DAC/amps performance.
This does not come as cheap as the used DAC or amps though.

 

[nyxnyxnyx]

Can someone tell me how can I manage to feed 5v to this amplifier through RCA connection?
Is this the same case with Topping L30 where I have to use specific DACs that can deliver more than the typical 2Vrms through RCA?

 

[_thelaughingman]

Can someone tell me how can I manage to feed 5v to this amplifier through RCA connection?
Is this the same case with Topping L30 where I have to use specific DACs that can deliver more than the typical 2Vrms through RCA?

I'm not sure that'll be feasible over RCA, since RCA is unbalanced and only outputs 2v. I may be wrong but you'd need a balanced out from the DAC to balanced in to get the 5v across.