Sabaj A30a announced

[antcollinet]

Thank you for reporting the test results.

I have found from your testing that the A30a works fine.
There are two ways of thinking about SW output.
One is to mix and output R-ch and L-ch, and the other is to use only either R-ch or L-ch.
Since the deep bass that SW takes charge of is included equally in the left and right channels, there is no problem with only one of them. In particular, the A30a has a low passband frequency, so it is OK to use only one side.

He is saying there is no bass output from the SW output if the bass is on the left channel of the music - either USB, or Left RCA input.

This must be a fault. Bass is not equally in L&R Of music. If the amp has only one SW output, it should take that from the low pass filtered version of both channels summed together.

 

[Toku]

He is saying there is no bass output from the SW output if the bass is on the left channel of the music - either USB, or Left RCA input.

This must be a fault. Bass is not equally in L&R Of music. If the amp has only one SW output, it should take that from the low pass filtered version of both channels summed together.

I explained that.
If such specifications are unacceptable to him, he either contacts Sabaj and asks for improvements or gives up using the A30a.
I think the SW signal is probably generated by software.
Like you, I don't like using only one channel for SW output.

 

[Toku]

My primary source is my PC, the A30A is linked by USB, drivers installed.

test are made with one song and one "demo"

Blossomn - Plunge: the bass line is sweeping from right to left, pretty clear on headphones.
When i first listen to it with the A30A i've noticed the bass line have changed, like a hole, then i've listened to a "demo" on youtube

this "demo":

SW input of the subwoofer is a line-in, 2 RCA White\Red

i tried:
- a30a sw-out -> mono-rca -> L channel input SW
- a30a sw-out -> mono-rca -> R channel input SW
- a30a sw-out -> Y rca -> L+R channel input SW

same result, there is bass only on the right channel, when only the left channel play, no bass.

I tried with an external dac:
PC> USB> Topping D10S > stéréo RCA> A30A, with the same three output as before, same result

I went back to another amp, with a sub-out:
Onkyo TX8020: https://eu.onkyo.com/en-GLOBAL/audi...-amplifiers/stereo-receivers/tx-8020/p/157415

PC> USB >D10S>optical> TX8020 > Y RCA> Subwoofer. no problem.

Just tested the SW output on my A30a.
As a result, only R-ch is output to SW.
So either Sabaj is designed that way or there is a bug in the software of the digital processing part of the SW output.
The truth is we have to ask Sabaj and wait for an answer.

 

[Toku]

Thanks for your reply, Can you have a picture of the back of the machine to see your link?

Using my A30a, I confirmed that the SW output is only R-ch.

I know that there are two types of SW output methods: one that outputs either one of R-ch/L-ch, and the other that outputs a mixture of R-ch/L-ch.
Is the operation of A30a outputting only R-ch to SW a specification of Sabaj?

 

[Tonton_ZEeD]

Just tested the SW output on my A30a.
As a result, only R-ch is output to SW.
So either Sabaj is designed that way or there is a bug in the software of the digital processing part of the SW output.
The truth is we have to ask Sabaj and wait for an answer.

Thank you for you patience and testing

I hope it can be corrected via a firmware update.

 

[antcollinet]

Just tested the SW output on my A30a.
As a result, only R-ch is output to SW.
So either Sabaj is designed that way or there is a bug in the software of the digital processing part of the SW output.
The truth is we have to ask Sabaj and wait for an answer.

Designed that way or not - it is a fault.

Not fit for purpose. You can't use a Sub if it only plays half the bass. We're not talking AVR LFE tracks here.

@peterwen

 

[kaopad999]

Didn't a member here have one of these Sabaj amps blow up on him a couple of months ago?
Sure looks nice but i'm not sure if i'm willing to spend ths amount of money on a Chinese amp just yet until they have stood the test of time and offer a 2 year warranty

 

[TonyJZX]

They do offer a 2 yr warranty... hifi express (which I'm sure is an official outlet), shenzen audio, apos all do this... however the aggravation of having to send it back to China at your cost and the like puts a dampener on things.

And lets just say China companies and online stores do not have the reputation for being consumer friendly, rightly or wrongly.

At $600 its up to you whether you think its worth betting it all on one horse. I have no issue with about half that but its depends on your pain threshold.

 

[Tonton_ZEeD]

Designed that way or not - it is a fault.

Not fit for purpose. You can't use a Sub if it only plays half the bass. We're not talking AVR LFE tracks here.

@peterwen

I agree, it's a flaw.

The ability to control the subwoofer volume with the remote is convenient for my use. It was a key point to buy the a30a over my other option: Aune VIII magic dac + audiophonics MPA-S250NC XLR

 

[Toku]

I checked the SW output with another amplifier at hand.

SMSL A300 SW output is RCA monaural same as A30a.
When I tested it, it was a stereo mix output of L-ch and R-ch.

SMSL AO200's SW output is L-ch and R-ch stereo output. This type connects to the stereo input on the SW side.

 

[antcollinet]

I checked the SW output with another amplifier at hand.

SMSL A300 SW output is RCA monaural same as A30a.
When I tested it, it was a stereo mix output of L-ch and R-ch.

SMSL AO200's SW output is L-ch and R-ch stereo output. This type connects to the stereo input on the SW side.

Pretty much what you would expect. Though with the AO200 it would be nice if it could be set for internal stereo mix to one or both of the sub outputs for use with subs that only have one RCA input, or if you want to use multiple subs both with the same (mono) input.

 

[longma]

They do offer a 2 yr warranty... hifi express (which I'm sure is an official outlet), shenzen audio, apos all do this... however the aggravation of having to send it back to China at your cost and the like puts a dampener on things.

And lets just say China companies and online stores do not have the reputation for being consumer friendly, rightly or wrongly.

At $600 its up to you whether you think its worth betting it all on one horse. I have no issue with about half that but its depends on your pain threshold.

As i posted the question not long ago, for $600, is it better to go with Hypex amp for power and reliability?
If A30 is better measured, do we hear the difference?

 

[peterwen]

Just tested the SW output on my A30a.
As a result, only R-ch is output to SW.
So either Sabaj is designed that way or there is a bug in the software of the digital processing part of the SW output.
The truth is we have to ask Sabaj and wait for an answer.

This problem has been solved, the firmware is being uploaded to the official website and can be updated to solve the problem. I'll send the firmware link here
Thank you so much

 

[peterwen]

I agree, it's a flaw.

The ability to control the subwoofer volume with the remote is convenient for my use. It was a key point to buy the a30a over my other option: Aune VIII magic dac + audiophonics MPA-S250NC XLR

Please try to upgrade by this firmware

 

[peterwen]

Thank you for you patience and testing

I hope it can be corrected via a firmware update.

Try that firmware, if have any problem after the upgrade please connect with me that I can change it.
Thank you so much.

 

[Toku]

Please try to upgrade by this firmware

Thank you for your quick response.
I updated the FW of my A30a immediately.
I have confirmed that the SW output is properly mixed with R-ch and L-ch.

Arigatou! 谢谢你。

 

[antcollinet]

Please try to upgrade by this firmware

Brilliant response from Sabaj here. Congrats to you and the team.

A pity some other organisations can't be equally responsive.

 

[peterwen]

Thank you for your quick response.
I updated the FW of my A30a immediately.
I have confirmed that the SW output is properly mixed with R-ch and L-ch.

Arigatou! 谢谢你。

Thank you for your quick response.

 

[Tonton_ZEeD]

Try that firmware, if have any problem after the upgrade please connect with me that I can change it.
Thank you so much.

Firmware upgraded, work great

Thank you and your team !

 

[peterwen]

Brilliant response from Sabaj here. Congrats to you and the team.

A pity some other organisations can't be equally responsive.

Can you tell me the organization name? Or I can go up and update