What's happened to the sa-36a pro - not tpa3118?

Hey all, new to the forum, great info here, even if you're a novice (me).

But, I am a discriminating listener, had done some research here and elsewhere and felt confident that buying a smsl sa-36a pro would be a good choice - with all the high marks given to the tpa3116/3118 chips.

When I received it, the back voltage markings were suspicious (12-15v instead of 12-24v), so I opened it up and here's what I saw: not a tpa3116/3118 but instead a TDA7492PE chip! And seams to be under-powered. I've ordered 3 now from 3 different sellers: Amazon ships and sold by, CrazyEve/Amazon, and an ebay seller sourced in China that seemed legit and shipped very fast (US warehouse probably). The latter is the one I have now. It's strange because the board is printed with sa-36a (not pro) and its NOT using the older ta2020 tripath chip.

What do you think? Is this counterfeit, or SMSL changing the build? How would it measure up against the 2014 2.1 and 2.2 versions of sa-36a pro?

This build looks like a downgrade to me, but I don't know anything, I'm looking for some wordly input from those in the know here. Thanks

2 different units opened up here with slightly different builds.
 

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The one I still have is the first pic with the single capacitor. Would you still recommend a pair of the NCC KZH 2200uF to replace the single? Or something else?

Also from what I've read I thought a heat sink was recommended for the tda7492. Based on what you can see on the board is it worth modding this?
 
The one I still have is the first pic with the single capacitor. Would you still recommend a pair of the NCC KZH 2200uF to replace the single ?

Yes - if they fit, put them in. Can't have too many caps :D I notice there are holes to fit two caps, be careful to get the right polarity as caps explode if you connect them up reversed.

Also from what I've read I thought a heat sink was recommended for the tda7492. Based on what you can see on the board is it worth modding this?

From what I can see in the DS the chip has an exposed pad on the underside. There looks to be some kind of heat spreader built into the PCB which connects thermally to that pad. So I think you're probably fine.
 

irribeo

Member
2013-04-01 2:46 pm
Yes smsl (ali) is selling a 36a with pro frontplate, so something changed in their routemap, it was intended to be a 36a, the pcb shows. One can only speculate, was it landslide related maybe etc Looks like all new smsl simple amps are 7492 btw, the a2, mini5 and 36a (pro), so they probably bought a lot of those:)
 
There are two versions on Amazon, make sure you get the one that says "SMSL SA-36A PRO 2* 20W TPA3118D2DAP Amp Stereo Digital Amplifier ".

Or are you saying, despite ordering one that says on Amazon it is TPA3118, you got an STI chip TDA7492?

Amazon.com: SMSL SA-36A PRO 2* 20W TPA3118D2DAP Amp Stereo Digital Amplifier + 12V Power Adapter: Electronics

If you got the wrong one exchange or return it.

Yes I've ordered and returned 2 already from Amazon, one of them was from your example CrazyEve. The 3rd try was from ebay (single cap image in op). I was even comparing Amazon's ASIN number to see if that would help. Amazon's listings for this product are a mess - on some the product header says one chip, but the description says another chip, and the pictures may show a different version again.

If this is legit (whatever that means), the only online vendor I can see that has corrected their listing is shenzhenaudio I emailed for details and they did not respond.
SMSL SA-36A Pro 20WPC TDA7492PE Digital Amplifier + Power Adapter - Professional Audio Store - Shenzhenaudio.com

I'm guessing the resellers don't know, the only evidence is the 12-15v marking on the back.
 
Yes smsl (ali) is selling a 36a with pro frontplate, so something changed in their routemap, it was intended to be a 36a, the pcb shows. One can only speculate, was it landslide related maybe etc Looks like all new smsl simple amps are 7492 btw, the a2, mini5 and 36a (pro), so they probably bought a lot of those:)

I thought the sa-36a (not pro) was older generation, using the TA2020 chip. This almost looks like their pulling whatever's laying around in the bin.....
 
When did you buy it? If you do decide to open it, please post a picture of what you find. A hair dryer to soften the glue and a thin implement like an artist paint knife to get it started, then tweezers will remove it cleanly and re-apply after.

I think a warranty argument when the product doesn't match the advertised spec would be pretty weak from a reseller or SMSL, who from irribeo's post is a subsidiary of Ali? The SMSL product page still lists 3118 as the spec:

http://smsl-audio.com/index.php?c=msg&id=1252

With these direct from China products who knows what "warranty" really means.
 

Mchl

Member
2015-03-23 10:42 am
I've just got mine from Aliexpress:

New SMSLSA 36A Pro 20WPC TPA3118D2 Digital Amplifier Free Shipping WITHOUT POWER ADAPTER-in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group

As you can see both the title and the description says it's TPA3118D2DAP, however when I opened mine it's the V3.1 version with TDA7492PE :/ It does not look at all as what I'd expect from SMSL.

Didn't have a chance to power it up yet (don't have an appropriate power supply at this moment)

I think I'll start a dispute on Aliexpress and see what comes out of it.
 
Genuine TPA3118 36A Pro

Ok, I killed the holographic anti-tamper warranty void sticker opening this up but I had to find out if I got a fake 3118. I guess I did ok as it is the 3118 layout and chip says 3118, although doesn't say "TI". I noticed that the C45 and C46 caps are empty - do these normally come with something there like OSCON's or is that typically an upgrade people do themselves? As long as I have it open should I go ahead and solder a couple of Panasonic SEPF 330uF 25V's in place?

I forgot this amp has bootstrap snubbers - can clearly see the 10R resistors and caps connected to main output traces.

Note that mine is v2.2 dated 2014/6/6 whereas the TDA variants are v3.1 and v3.2 as shown in Post #1. I bought mine last October from Amazon.

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mt490

Member
2010-06-09 2:32 pm
Is there a thermal pad to conduct heat to the case underneath the TDA versions?

If I remember correctly the early 7492 amps by Sure ran into reliability issues because of their cooling regime. But that might also be why SMSL are only using them for 15V max.
 
xrk971 there a some posts from the mega thread TPA3116D2 Amp that show variants of the 2.2 layout:

http://www.diyaudio.com/forums/class-d/237086-tpa3116d2-amp-394.html#post3994924
http://www.diyaudio.com/forums/class-d/237086-tpa3116d2-amp-454.html#post4032149

- you seem to have some differences, these two links show the c45,46 caps already there, different filter caps. But it's a lot closer to what's expected than what I got...:mad:

The sa-36a pro is starting to look like a box a chocolates.....
 
xrk971 there a some posts from the mega thread TPA3116D2 Amp that show variants of the 2.2 layout:

http://www.diyaudio.com/forums/class-d/237086-tpa3116d2-amp-394.html#post3994924
http://www.diyaudio.com/forums/class-d/237086-tpa3116d2-amp-454.html#post4032149

- you seem to have some differences, these two links show the c45,46 caps already there, different filter caps. But it's a lot closer to what's expected than what I got...:mad:

The sa-36a pro is starting to look like a box a chocolates.....

Looks like the simply left off the caps C45 and C46 to save money. Then later realized no one noticed and said, let's swap out the 3118 for the 7492, no one will notice and no will bother because we have such a good reputation already (thanks to xrk on DIYA). And if we stick a fancy do not remove or void warranty sticker on it, that will deter another 95% of the people from ever opening it to check.

This could actually be a class action if they purposely have been misleading the buyer (and even the reseller). You would have to purposely do it because the TDA7492 is a completely different amp.
 

irribeo

Member
2013-04-01 2:46 pm
The open c45c46 has been noticed by several buyers and mentioned in multiple threads multiple times. SMSL is selling you SA36aPRO, changes to specifications and parts can occur without prior notice, you know, it is the beauty of branding we like. You read a review of Macbookpro and screen is fabulous, then you buy same typenumber and screen is flawed, you go to Apple service point and they say, yes now it is eg Samsung screen, it used to be eg LG screen and the new screen is up to spec:) Just useless for your purpose. etc etc