Sabaj A30a announced

[douede]

If you quote me, please provide the full context.
"Important! If you want to open the Sabaj A30a, don't try to remove the bottom panel! They will damage or destroy your device! The first thing to do is to remove the lid!"
Or did you manage to dismantle the floor first?

IMHO, providing the "full context" had no added utility/value for the purpose and would have been unnecessarily "heavy" for the site (pictures...).
My apologies; in fact and in order to access the underside of the PCB, I finally remembered and realised that I hadn't removed the floorboard, so I corrected my post: As you said, removing it would damage the PCB, due to the 4 solid output wires and the screwed back connectors (coax+sw).

 

[GiBo61]

Out of curiosity: why do you want to open your Sabay?

 

[douede]

...in order to tweak/improve it : binding posts, solder joints, capacitors...

 

[Toku]

I also purchased a Sabaj A30A. It works with Heco Aurora 700. I just have doubts whether it works properly. From about 80 on the scale it cuts off the left or right channel or both... Restarting prevents playback. Is this how overload protection works? How is it with you? I would like to point out that I usually listen at levels 30-36. I just wanted to check the possibilities when listening loudly. The amplifier simply does not allow operation with high distortions and cuts off the channels, do I understand correctly?

I was curious when I saw your report because it seems very similar to the problem I experienced.
In the case of your A30a, if you turn the power switch on the back panel OFF/ON when the sound stops producing, does it return to operation?
My trouble report is earlier in this thread.

Sabaj A30a announced

From an "audioscientific" perspective there won't be a lot of alternatives, as we expect decent+ measurements from that device. These Auroras, don't get me wrong, won't be able to reveal the tiniest differences between different kind of quality gear. Sonically it should be a huge step forward...

www.audiosciencereview.com

I reported the symptoms to Sabaj in China, but they could not find the cause and ended up sending my A30a back to China for investigation.
Investigation revealed that the amplifier chip's heat spreader was not installed correctly and could not cool sufficiently, causing the heating protection function to work.
Of course Sabaj sent me the new A30a.

 

[Sebcior]

I was curious when I saw your report because it seems very similar to the problem I experienced.
In the case of your A30a, if you turn the power switch on the back panel OFF/ON when the sound stops producing, does it return to operation?
My trouble report is earlier in this thread.

Sabaj A30a announced

From an "audioscientific" perspective there won't be a lot of alternatives, as we expect decent+ measurements from that device. These Auroras, don't get me wrong, won't be able to reveal the tiniest differences between different kind of quality gear. Sonically it should be a huge step forward...

www.audiosciencereview.com

I reported the symptoms to Sabaj in China, but they could not find the cause and ended up sending my A30a back to China for investigation.
Investigation revealed that the amplifier chip's heat spreader was not installed correctly and could not cool sufficiently, causing the heating protection function to work.
Of course Sabaj sent me the new A30a.

In my case, it looks like overload protection, not thermal protection. It will amplify the amplifier when it is just turned on, cold, and as soon as the distortion level reaches 1%, it cuts off the channels. So far, I haven't noticed anything happening due to the operating temperature, the fan only turns on for a moment when starting up, and then I didn't hear it working anymore, the amplifier works 16 hours a day. I installed WIIM mini, it plays perfectly, better than the Google Chromecast audio I had before. I only had a problem with connecting two SPDIF sources to the amplifier, I solved it by cutting the plugs from the cables and connecting them together... such a quick connection, but it works, either WIMM or TV plays. SPDIF Sense set to 3 by default.

 

[Sebcior]

I was curious when I saw your report because it seems very similar to the problem I experienced.
In the case of your A30a, if you turn the power switch on the back panel OFF/ON when the sound stops producing, does it return to operation?
My trouble report is earlier in this thread.

Sabaj A30a announced

From an "audioscientific" perspective there won't be a lot of alternatives, as we expect decent+ measurements from that device. These Auroras, don't get me wrong, won't be able to reveal the tiniest differences between different kind of quality gear. Sonically it should be a huge step forward...

www.audiosciencereview.com

I reported the symptoms to Sabaj in China, but they could not find the cause and ended up sending my A30a back to China for investigation.
Investigation revealed that the amplifier chip's heat spreader was not installed correctly and could not cool sufficiently, causing the heating protection function to work.
Of course Sabaj sent me the new A30a.

Can you force the overload system to work? Have other Sabaj A30a owners ever experienced this reaction?

 

[ModDIY]

Can you force the overload system to work? Have other Sabaj A30a owners ever experienced this reaction?

I have never had a cutoff due to distortion of more than 1%. My speakers are 8ohms with at least 2.9ohms, efficiency of 91db. On several occasions I turned the volume up to very high power and in a medium sized living room, and music containing a lot of low frequencies.

 

[Ze Frog]

I think the sabaj a30a looks amazing, I really want to buy it.

I'm just worried about having the subwoofer issue which seems to be the only deal breaker. Are they pretty good with customer service regardless if you purchase from Amazon, hifi Express, or ali Express?

The other issue is requesting the adjustable filter extend <70hz seems like a nice to have however it's still completely acceptable. Is there anything else that might be a deal breaker?

Yeah, the sub issue is a bit of an issue really for me also.

Anyone know if this has been fixed yet?

 

[syzygy]

Yeah, the sub issue is a bit of an issue really for me also.

Anyone know if this has been fixed yet?

From the manual - available on the Sabaj website:

 

[syzygy]

 

[Ze Frog]

View attachment 354064

Do you own this and run a subwoofer? Does this actually fix the issue aside from on paper? I did see this, but I don't really take manafacturers word for things.

 

[Roland68]

Yeah, the sub issue is a bit of an issue really for me also.

Anyone know if this has been fixed yet?

The subwoofer frequencies are a function of the STA309A DDX chip used and are fixed. That cannot be changed.

 

[Ze Frog]

The subwoofer frequencies are a function of the STA309A DDX chip used and are fixed. That cannot be changed.

View attachment 354119

So volume level is consistent now?

The bass management frequency selection was never an issue preventing me from looking deeper, just the changing of volume was apparently only correct at certain points.

 

[Roland68]

So volume level is consistent now?

The bass management frequency selection was never an issue preventing me from looking deeper, just the changing of volume was apparently only correct at certain points.

According to Sabaj, the volume curve of the subwoofer has been adjusted, but I haven't tried that yet.
Maybe someone can confirm that it works after the update?

 

[GiBo61]

Even after the latest (and only) Sabaj A30a firmware update, some users complained about the lack of linearity of the volume curve of the main speakers and that of the subwoofer. In my 2:1 setup (Elac Vela BS403 and a Martin Logan Dynamo 700w sw) I cannot confirm the issue. Sure, sometimes the bass are too much or too little but I find it more related to the type of music I'm playing than to the issue mentioned before. My only complain about the Sabaj subwoofer implementation is the lowest sw crossover frequency that is limited to 70 Hz (it would have been better to be able to select a lower frequency cutoff such as 50 or 40 Hz when using floorstanding speakers), but, as mentioned by Roland68 above, the limitiation is in specs of the STA309A DDX chip used by Sabaj and I guess it can't be changed with a firmware update.

 

[Tonton_ZEeD]

Even after the latest (and only) Sabaj A30a firmware update, some users complained about the lack of linearity of the volume curve of the main speakers and that of the subwoofer. In my 2:1 setup (Elac Vela BS403 and a Martin Logan Dynamo 700w sw) I cannot confirm the issue. Sure, sometimes the bass are too much or too little but I find it more related to the type of music I'm playing than to the issue mentioned before. My only complain about the Sabaj subwoofer implementation is the lowest sw crossover frequency that is limited to 70 Hz (it would have been better to be able to select a lower frequency cutoff such as 50 or 40 Hz when using floorstanding speakers), but, as mentioned by Roland68 above, the limitiation is in specs of the STA309A DDX chip used by Sabaj and I guess it can't be changed with a firmware update.

A member of this forum have post some measurment on this tread, there is a sort of "loudness" when the volume control is set below 40.

Sabaj A30a announced

I do not use the USB input. Can you better explain what you mean when you say "noise mixes into the SW output when using USB input"? It is a symptom that noise is mixed in the subwoofer output when the input of the A30a is switched to USB. The noise sounds like white noise or digital noise, and...

audiosciencereview.com

It was a problem for me since i have buy the A30A but i have find a solution.
My level volume control is set to 70 all the time and i control the volume via the windows master volume. Poor solution but it's working for me.

 

[ModDIY]

A member of this forum have post some measurment on this tread, there is a sort of "loudness" when the volume control is set below 40.

Sabaj A30a announced

I do not use the USB input. Can you better explain what you mean when you say "noise mixes into the SW output when using USB input"? It is a symptom that noise is mixed in the subwoofer output when the input of the A30a is switched to USB. The noise sounds like white noise or digital noise, and...

audiosciencereview.com

It was a problem for me since i have buy the A30A but i have find a solution.
My level volume control is set to 70 all the time and i control the volume via the windows master volume. Poor solution but it's working for me.

I do exactly the same, except at 60 and optical input via Wiim Pro.

 

[GiBo61]

A member of this forum have post some measurment on this tread, there is a sort of "loudness" when the volume control is set below 40.

Sabaj A30a announced

I do not use the USB input. Can you better explain what you mean when you say "noise mixes into the SW output when using USB input"? It is a symptom that noise is mixed in the subwoofer output when the input of the A30a is switched to USB. The noise sounds like white noise or digital noise, and...

audiosciencereview.com

It was a problem for me since i have buy the A30A but i have find a solution.
My level volume control is set to 70 all the time and i control the volume via the windows master volume. Poor solution but it's working for me.

I have seen the measurements done by member of this forum (robbie) regarding lack of linearity between the Sabaj A30a volume of the main speakers and the subwoofer. Althoug robbie made a good job, he is comparing the SPL (in db) at 125 Hz generated by two different speakers (main: Heco Aurora 700 and sub: SVS sb 1000 pro) at different A30a volume settings. I'm no expert but there are many variable playing in this scenario, among them: the measurements have been apparently done with the microphone in a different position in the room for the sw and the mains; furthermore the frequency response of each speaker changes with volume so is not garanteed that if you double the power provided by the amp to the speaker you get 3 db more of SPL at your frequency of choice (i.e.125 Hz in the case of robbie's test) and this behaviour differs among different speakers. In this post is an example of what I'm talking about and in Erin's Audio Corner speaker reviews you will always find a plot named "Dynamic Range" that indicates how much SPL is lost or gained at any frequence when the speaker is played at 4 different output volumes.

 

[syzygy]

I have seen the measurements done by member of this forum (robbie) regarding lack of linearity between the Sabaj A30a volume of the main speakers and the subwoofer. Althoug robbie made a good job, he is comparing the SPL (in db) at 125 Hz generated by two different speakers (main: Heco Aurora 700 and sub: SVS sb 1000 pro) at different A30a volume settings. I'm no expert but there are many variable playing in this scenario, among them: the measurements have been apparently done with the microphone in a different position in the room for the sw and the mains; furthermore the frequency response of each speaker changes with volume so is not garanteed that if you double the power provided by the amp to the speaker you get 3 db more of SPL at your frequency of choice (i.e.125 Hz in the case of robbie's test) and this behaviour differs among different speakers. In this post is an example of what I'm talking about and in Erin's Audio Corner speaker reviews you will always find a plot named "Dynamic Range" that indicates how much SPL is lost or gained at any frequence when the speaker is played at 4 different output volumes.

That's very interesting. I'd been wondering how this was determined by either reports of 'SWO too high' & ''SWO too low' wrt. main speaker level, and I had to imagine that the room nodes & acoustics must be hard to eliminate (as it always is for <100Hz) in real-world installations.
-I imagine both of these individual case descriptions were from use in normal-scale residential rooms- do we know?

and also - given the DSP nature of level control in the signal path, any inconsistency between the SWO & Mains would almost need to be deliberate, such as when applying any of the EQ settings - but they should be uniformly applied to the spectrum - anything else would require a deliberate deviation of a path.

further, it seems like we'd also hear these observations with any similar amp with a SWO - certainly (I think) if they use the STA309 DDX chip - the closest being VMV A2?
-curious if anyone ever reported bass level management issues with that model?

But the Dynamic Range 'curve' potentially differing between the mains & sub (not to mention multiple subs) seems like it would further confound judgment on this.
-isn't this a common problem in system installations with subs?

 

[Nahkarankaisija]

Thinking of buying the Sabaj A30A to replace my Naim Nait 5si + SMSL SU-6 DAC combo, mainly to get some money back from selling the separates and getting some desk space back. I am using high efficiency DIY speakers without a sub so not very concerned about the potential sub volume issues but I am interested about the sound quality of the Sabaj, would you recommended the Sabaj for purely 2 channel listening or is there a better all-in-one amplifier in the same price range?