SMSL A100 (ma 12070)

[Zek]

Sony Core 5 speakers

The weakest spot in the chain...

 

[cycologist]

I bought one of these -- it's small and light and doesn't heat up. Just over two weeks to middle of the USA from AliExpress. It's for a desk system so I'm not asking too much of it. Plug the USB into a Windows PC and it just works, and switches itself over to the USB input besides. Windows doesn't say anything about it other than it's "USB AUDIO" and I haven't opened the case. To do that, it looks like you'd have to pull off the front volume knob, then there are two small screws underneath and more hiding underneath the feet. Bluetooth just works. Aux input is silent with the volume up. There is no turn-on thump and you can switch the input with the little button at top right without it exhibiting any bad behavior. The indicator light itself is tiny and not intrusive at all. Binding posts are serviceable. I'm using bananas, and you could fit spades underneath...maybe. It's a little tight for some of the big spades I have on amps at home, especially on the lower bingind post near the power cord. I am interested in how it measures, but so far this is nice for what I'm using it for and doesn't have any annoying quirks.

 

[dayend]

https://shopee.tw/-%E9%9F%B3%E6%A8%82%E9%81%94%E4%BA%BA-%E7%B5%95%E4%BD%B3%E5%85%A5%E9%96%80%E4%BE%BF%E7%95%B6%E7%9B%92-SMSL-A100-%E5%B0%8F%E5%9E%8BD%E9%A1%9E%E6%93%B4%E5%A4%A7%E6%A9%9F-Hi-Res-%E8%97%8D%E8%8A%BD5.0-PC-USB-AUX-%E4%B8%BB%E5%8B%95%E4%BD%8E%E9%9F%B3-i.22709512.14535936972

I found on a Chinese Shop site that the SMSL A100 DAC USB supports only 16BIT/48KHZ.
I don't know what DAC CHIP is, but it has a low specification.

 

[ModDIY]

Ideally an external DAC is better.

Despite all this amp is still a good deal.

 

[surfy]

Hello,
I bought this amp to play with Q acoustic 3020 speakers. With the inside DAC, it's not very good. With an external DAC ES9018, it's wonderful for pricing (better than my Cyrus XPA with external preamp).
I ask to SML whith what OP amp, I can upgrade the two TL072C inside (SOIC soldering on the board amp): Kelly says to me OPA1678. When I receive them, I will upgrade my amp with them.

 

[galapogos]

Hi, is this in stock anywhere?

 

[surfy]

I bought them on AliExpress to this seller (100% positive feedback). I will test them on one of my dacs to see if they sound good and are authentics.
It is not a widely distributed reference, the risk is lower.

4.04US $ |Amplificateur Opérationnel Opa1678idr Opa1678, Patch Sop-8, Nouveau, Original, En Stock, 5 Pièces/lot - AliExpress

Achetez malin, vivez mieux! Aliexpress.com

fr.aliexpress.com

 

[surfy]

See to this seller: AliExpress HongQi Global Store. Unabled to post the internet adress.

 

[surfy]

Oups... The link was in the previous message.

 

[galapogos]

@surfy I can't seem to find the product in the HongQi Global Store.

 

[surfy]

here

4.04US $ |Amplificateur Opérationnel Opa1678idr Opa1678, Patch Sop-8, Nouveau, Original, En Stock, 5 Pièces/lot - AliExpress

Achetez malin, vivez mieux! Aliexpress.com

fr.aliexpress.com

 

[galapogos]

That's a link to an opamp, not the A100.

 

[muslhead]

Hi, I got a response from SMSL, I had asked what DAC chips are this used for USB..

Hello, our A100 is a power amplifier, which is the chip of MA12070.

Thank you SMSL for your respond.

This is the problem very often with SMSL. They make great products, but their customer service seems average based on a few threads here.

"Average" is a kind, politically correct representation. The problem, as i found out, is when you have a defect with one of their products, "average" does not cut it and not the time to discover "average"

 

[surfy]

For Galapagos: bought on HiFiExpress.

 

[galapogos]

Thanks. They don't seem to carry that anymore.

 

[surfy]

That's it! I changed the 2 TL072C op amps with 2 original Texas Instruments LME49880s (not with OPA1678s which I still haven't received). The amp is transformed. What a slap! My Cyrus can go fuck himself! This op amp is now obsolete, in this case the LME49723 would also be a great choice (balanced spectrum, great soundstage, super dynamic). Do the swap! Otherwise the amp is very well made in-house.

 

[TheBatsEar]

That's it! I changed the 2 TL072C op amps with 2 original Texas Instruments LME49880s (not with OPA1678s which I still haven't received). The amp is transformed. What a slap! My Cyrus can go fuck himself! This op amp is now obsolete, in this case the LME49723 would also be a great choice (balanced spectrum, great soundstage, super dynamic). Do the swap! Otherwise the amp is very well made in-house.

Cheers. Didn't think changing the OPAMP would make such a difference in those kind of devices.

Would you be able to provide some pics of the PCB and inside? I don't think we have seen a picture of the back either. Thanks mate.

 

[surfy]

I will do it this week end. I have to reopen the amp!

 

[Nocturnal-G]

I listened to the amp and think its an excellent amp for the money.

Pros -
- Small form factor
- Gets uncomfortably loud (Sony Core 5 speakers)
- No hissing, popping
- Excellent detail in music
- Runs cool even when being pushed hard

Cons -
- Internal DAC is so so (didn't test the Bluetooth input just USB)
- No tone controls
- No remote
- Can sound a bit thin / clinical (will listen again after it breaks in, upgrade the power cable)
- The speaker terminals in the back could be better


Overall, I think the amp is an excellent value. Sounds great especially for how small it is!

 

[galapogos]

Where can one buy one now?