Aiyima A07 PRO

[Scrufboy]

Heatsinks fully prepared for the 2, 12 volt regulators

This will probably be the only modification I do before I decide to send this to Amir. Still kind of put off by the theft.

 

[trungdtmc]

Heatsinks fully prepared for the 2, 12 volt regulators

This will probably be the only modification I do before I decide to send this to Amir. Still kind of put off by the theft.

There lm78xx regulator step down 13,xxV from xl7015e output, so they don’t get hot

 

[Scrufboy]

There lm78xx regulator step down 13,xxV from xl7015e output, so they don’t get hot

You are not following along. In "stock" configuration they shouldn't get hot. I'm however installing several SparkosLabs SS3602 opamps. So there is a concern for those getting hot. This has been thoroughly discussed and confirmed by Andrew at SparkosLabs and is being done as a simple, yet inexpensive and reasonable precaution.

Do try to keep up.

 

[Scrufboy]

Hey gang.. I need to bring your attention to some details.

I find it interesting that there is no negative leads attached to the speaker binding posts. Not that I can see. See the pics.

Also... I have confirmed that SparkosLabs op-amps or larger IC op-amps on Dip8 boards will fit or should fit in U16 without contact with the heatsink.

However, you could reduce that edge by removing it and sanding that edge down a bit. Make sure you have thermal paste for the chip if you remove it. Clean it up and apply new paste. Many of you will know this


In the other positions, larger op-amps like a staccato won't work in any position. The sockets are just too close together.

Burson's should fit. The case will need to be cut or their adapters used. I am working to secure a set because based on the research done by others. A combination of Sparkos and Burson V6 vivids will yield the best results.

In the position relationship between U3 and U8. The SparkosLabs are kind of tight. But appear to be fine.


If you do use any discrete op-amps in these positions... In U2, U3 and U8 you will need Dip8 risers. You will not necessarily need any risers on U9 and U16.

If you are rolling Burr Browns, you will most likely need risers in the same positions.

Also... It is important to note that it literally makes no sense what the Aiyima rep said about these op-amp positions.

The rep said...

"U8 input buffer amplification

U9 Tone

U2 left channel single end differential

U3 right channel single turn differential

U16 aux output buffer
This is the reference corresponding to the operational amplifier chip"


We can make sense of U8, U9, and U16

However... The wording used by Aiyima rep for U2 and U3 do not make any sense at all.

First... The amp has no balanced output or input. It is single ended. So using the term differential in describing U2 and U3 makes no sense. It is single ended, period.

Secondly, you cannot find any audio references in regards to single turn differential... You get automotive information.

So.. It begs the question why would the Aiyima Rep tell us the U2 and U3 do two distinctly different things... This makes absolutely no sense at all.

In discussing this with others, they agree that the Aiyima rep either is steeped in a language barrier issue. Or they just don't know enough to convey accurately.

Take that for what its worth and remember that this was the same rep that advised me incorrectly about my power supply, amp and my speakers in regards to my original A07

 

[Scrufboy]

Heatsink removed... We find a small aluminum piece that gets sandwiched between the actual heatsink and the TPA3255 chip.

Here I will be able to replace that with copper. Then, by using Thermal Grizzly Extreme, I will have the best possible heat removal.

This tiny low grade aluminum wafer is really an insult when they could have used copper.

 

[MCH]

, I will have the best possible heat removal.

A fan

 

[Scrufboy]

A fan

I wasn't asking... And you aren't making sense

But seeing that you're taking part of what I said out of context and not actually reading and comprehending the post... I'll help you out.

I already have fans cooling my current units. You would know this if you had actually decided to read and comprehend the thread.

But, let's do this... Why don't you tell me, based solely on your statement, how you think the Aiyima A07 Pro will benefit from a fan without the chassis having any vents? How will a fan, as you've advised, actually cool the unit?

How will that fan push air into a sealed box?

More importantly... You are responding to my commentary about the heatsink...
So, are you aware there are high quality and low quality thermal pastes? I am sure you are. Are you aware of the thermal conductivity of copper or aluminum?

So your comment has actually nothing to do with anything I was posting at all.

I improved the heatsinks ability to move heat off the chip by using a higher quality thermal paste and replacing the tiny aluminum wafer that Aiyima used with a pure copper wafer.

You're just saying "A fan" because...???

See my point?

 

[Berlun]

I think you forgot to indicate at the beginning of this thread what is and what is not allowed to be said here, so we don't bother you with comments that may offend you. Unbelievable.

 

[Scrufboy]

I think you forgot to indicate at the beginning of this thread what is and what is not allowed to be said here, so we don't bother you with comments that may offend you. Unbelievable.

The comment was not offensive...

The lack of attention to detail and the decision to comment from a completely uninformed and ignorant position. Taking part of a statement out of it's context, etc...

I think you forgot that actions like these are highly frowned upon here. Unbelievable!

 

[Scrufboy]

OK... Now back to what we are here for.. And because of what I found. This is now a review. And I am not pleased.

I'm appalled Aiyima. I just spent hours testing this amplifier and I have to say, I was right. I didn't need any blind testing at all. This Amp sounds absolutely amazing, but only through Bluetooth. Just as I suspected. Aiyima did something so that Bluetooth was very dynamic and punchy. Treble at 3 o'clock and bass at 2 proved to sound the best for the speakers I used. The speakers used in the test are Tritrix transmission line towers. I used a DROK power supply dialed in at 36V 10A and at 40V 10A.

I volume matched nvidia high definition audio from my monitor, A Schiit Hel 2E DAC and my phone. In order, the Bluetooth came out on top. The Nvidia monitor and the Schiit sounded the same. Very rolled of on the treble and lacking in dynamics or punch. It sounded very dull. Every member of my household could hear the differences immediately. Switching was able to be done really quickly. The differences were so distinct that you didn't even need a blind test.

What a ripoff! But you know... I suspected this. I will have the ability to try a couple of different DAC's soon. With that, I will also test the amplifier against two A07's. But this.. This A07 "pro" is not a "Pro" anything. It is a damn good Bluetooth amplifier... But in a chain. Ugh! It sounds sub par and sad.

Tell me why Aiyima, that a decent DAC, not the best though, sounded dull like an inverted V. But your Bluetooth implementation sounds completely amazing?!? I mean it's not even close... Buyer beware.

 

[Scrufboy]

Update Dec 31

I just installed all 5 SparkosLabs SS3602's and listened to 20 or so songs over a couple of hours.

When I started, I tested volume stage first separately and then added the tone op-amp. Then the U8 & U9 together and listened separately to Africa by Weezer, Raspberry Beret by Prince, Steve Winwood's Higher Love and Born in Space by Owane - for each test.

The sound improved dramatically! But wasn't fully realized until I added the 2 op-amps in the U8 & U9 spots. Subtle at first, but then more pronounced after the 4 main sockets were replaced with the SS3602's. The U16 slot had nothing to offer in this test because we are told that is the output stage for the 3.5mm Aux out.

But it did, in the end, improve. So much so that I could dial the tone controls back to zero from the previous 2 and 3 o'clock positions of the bass and treble knobs.

The RCA inputs sounded much, much better with the Sparkos than stock. At the 2 and 3 o'clock positions of the tone knobs, the Bluetooth was way too bright and harsh. But dialing the tone controls back to 12(0) proved to be much better. This still sounded a bit better than the RCA/DAC input though. The RCA did prove, with the Sparkos, to be more natural, analog and warm. It had a depth and presence that was well improved over the stock. Bluetooth still had more of a V shaped sound still but not at all like the stock op-amps.

The heatsinks I put on the voltage regulators got nice and hot as expected. Putting them on was smart. Getting air to move across these components with op-amps like Sparkos installed will be the right choice. I will have to vent the case for sure.

After about 20 tunes, swapping back and forth between RCA input and Bluetooth, I'm beat. It did get better and better as it went along though.

Tomorrow I will put some A07 'S on the same speakers. And test out how they sound in the same setup.

I'm still sad though that, out of the box, the unit seems to be tuned to be exciting for mobile and very flat at the edges and bumped in the low mids for RCA use. Almost like a reverse flattened v.

I would recommend this amp to anyone that wants a decent Bluetooth setup. Keeping it stock is OK too. However, if someone wants to put this in a stack and push a laptop/streamer/DAC setup through the A07 Pro, swapping the op-amps will help. But buying a better amp will be a better choice. SparkosLabs SS3602's cost $80 a piece. And while they certainly do a great job, I feel the money would be better spent on a better amplifier. And the original A07 is better, in my opinion, than the A07 Pro.

Want a real A07 pro? - Buy an A07 and Upgrade your power caps to 63v, swap out your inductors for some Sagami's. Replace your audio caps with the ones you want. Swap out your op-amps for the SS3602's. Repaste the heatsink with the best thermal paste you can afford and for goodness sake, vent your case. Then use a quality low-noise power supply and a robust DC cable.

I will continue to test and post findings if things are so discernable that they are worth mentioning. But testing the A07 pro against the A07 in both stock form and modified setups with SparkosLabs SS3602's will take quite a bit of time and dedicated listening and it will have to be as blind as possible so I will try to secure a proper A/B/X system for that.

Happy New Year.

 

[Scrufboy]

I think you forgot to indicate at the beginning of this thread what is and what is not allowed to be said here, so we don't bother you with comments that may offend you. Unbelievable.

Welcome to ASR where you are expected to do your due diligence when it comes to reading, comprehending and responding to posts. To know what you're talking about, and if you make particular types of claims - to be able to back them up with facts, data or logic.

You are new here - This correction is being offered as a courtesy - for your convenience. You may or may not read this.. But I refuse to be labeled incorrectly and I reserve the right to express and defend my position and have it understood clearly. My apologies to the other members of this community.

This isn't the place for the type of drama you tried to incite here. I don't need to post rules in my thread for you to know that.

A good tip for staying on topic is knowing what the topic is... Reading, being informed, paying attention to details, etc.

To further, in reply... There are no indicators at all that I was offended. So you're just projecting that onto my response to him to illicit something or be provocative. . Feel good about that?

I'm calling you out now publicly because you decided to do the same to me. If you want to make something more out this than what actually is... And falsely accuse me of something... Then you're at the wrong forum and perhaps you should excuse yourself and find another community.

Think... He made a two word response. What was his response based on and what was it designed to do?

His response was based on him, not reading and not actually understanding the context of the quoted item. Is that a logical approach? Is that respectful? Do you think that if someone quotes you... They should at least understand the context in which your quote comes from? or would you find this kind of blatant disregard offensive?

So... What was the context? Addressing the heatsink and improving it. Correct?

What does "A fan" mean then? It means he didn't even bother to comprehend and understand the context of the text he quoted before he replied. That is disrespectful. Is this what ASR is all about?

His reply, when he quoted me out of context is what then? Scientific? Smart? Logical? Respectful? Is it even informed? It's none of those things... Is that what ASR is all about?

What I did was expose how his two word answer was irrelevant based on his disregard for what the quoted statement used actually meant and what the context was. Does his and your blatant disregard for these facts align with the creed of this community? No they do not.

He could have simply apologized for not reading and fully understanding what I was conveying. Did he? No.

So... Are unsubstantiated, taken out of context, uninformed comments the accepted norm here? Or is it requested that people actually read, comprehend and be informed so they can have relevant responses? How can you participate in any discussion if you blatantly disregard common sense, common courtesy and choose to be uninformed? You cannot.

I then asked him to elaborate and clarify how he thought, based on facts, that a fan would work. Will a fan work to cool components inside a sealed box? The answer is no.
So... It is your contention that me asking him to back his statement with facts, elaborate or clarify, somehow is incorrect for me to do - here at ASR?

So ask yourself... Why is he posting a two word response that shows no regard for the content he is responding to? What are his goals? To help me? How exactly can he help when he never bothered to understand what he was replying to? Was I asking for help or advice? Or was I making a statement based on facts?

Here is a hint... The little emoji on the end of his 2 word reply conveys his motivation... His response wasn't helpful, it was moreover a jab. I know it and he knows it too. And you're defending that? Unbelievable!

You've either missed all of this or have chosen to ignore it... So your response is what is actually unbelievable. Your response is offensive. You have the unmitigated gall to come here and bring drama to my post by expressing yourself in the same uniformed and ignorant way he did in an attempt to correct or shine a negative light on me?

Your response is offensive to everything this community stands for. Because you brought drama by defended him when you, yourself were guilty of the same exact thing he was.

The problem is, In regards to my response to him - That I'm right. This is fact... Not opinion. Better thermal paste and using a wafer of copper will be more effective at removing heat from the tpa3255 chip than what was used. This is a known fact. And because I am not making claims to how many degrees cooler my methods gain me, etc. I am not required to show measurements. I bought the - best available to me - thermal paste for this application and copper is proven to be more thermally conductive than aluminum.

This was the context he removed when he quoted only part of my statement and replied with "A fan"

So basically, you are offended that I require people to read and comprehend the information posted so they can actually have an informed reply... and that they clarify their response by elaborating when asked. You actually need rules like this posted for you? Unbelievable.

My apologies again to the other members who are following this thread. I'm SIGMA and I don't tolerate this kind of ridiculousness in anyone. I see right through it and I call it out... You don't like it... That's on you... Be better or move along.

 

[Berlun]

Ok.

 

[Scrufboy]

There lm78xx regulator step down 13,xxV from xl7015e output, so they don’t get hot

With the SS3602 op-amps installed running at 40v 10A

One of heatsinks on the regulator closest to the op-amps gets near 150 degrees.

The one near the switches gets to about 120

The 5 volt around 127

The obscure chip near the large heatsink at the edge hits about 125

That seems kind of hot. The main heatsink only gets to about 85.

These temps are about 10 degrees less at 36V

I'd say installing the heatsinks turned out to be a good way to go. The case definitely needs some venting.

I don't believe it will be a problem with IC op-amps. I'm going to test with another set of NE5532, a set of OPA2134... And I may try to nab a set of OPA1612 as well.

 

[Holmz]

You need a fan

 

[Scrufboy]

You need a fan

I do use a fan in my setup now... A large 120mm black and red Noctua fan sits between my mini racks and blows through my original A07 and keeps it nice and cool. But even with the SparkosLabs op-amps installed, it never produces heat like this and I use it all day, every day.

But to reiterate what I already said on this subject. A fan can't blow air across heatsinks that are in an enclosed, sealed box. I need to properly vent the case of the A07 PRO first so a fan can even be useful. But that has always been the plan if I intended on keeping it. Which I don't think I will.

This is a test rig. I will most likely never use this A07 pro. Not unless I was to use it stock with Bluetooth in another room as some sort of background music system. I will probably just sell it though.

The A07 in certain variations is just a better implementation. A better amplifier overall. I have 3 units and they are all using different components. I will most likely just upgrade my other 2 regular A07's with these Sparkos op-amps, give them to my kids and use the remaining SS3602 in the Aune X8

I think the A07 Pro is decent... But it should not need this kind of money dumped into it to make it sound as good as it does stock through bluetooth. It's appalling.

You're much better off just buying a better amplifier. Or just buy an A07.

 

[Holmz]

I do use a fan in my setup now... A large 120mm black and red Noctua fan sits between my mini racks and blows through my original A07 and keeps it nice and cool. But even with the SparkosLabs op-amps installed, it never produces heat like this and I use it all day, every day.

But to reiterate what I already said on this subject. A fan can't blow air across heatsinks that are in an enclosed, sealed box. I need to properly vent the case of the A07 PRO first so a fan can even be useful. But that has always been the plan if I intended on keeping it. Which I don't think I will.

This is a test rig. I will most likely never use this A07 pro. Not unless I was to use it stock with Bluetooth in another room as some sort of background music system. I will probably just sell it though.

The A07 in certain variations is just a better implementation. A better amplifier overall. I have 3 units and they are all using different components. I will most likely just upgrade my other 2 regular A07's with these Sparkos op-amps, give them to my kids and use the remaining SS3602 in the Aune X8

I think the A07 Pro is decent... But it should not need this kind of money dumped into it to make it sound as good as it does stock through bluetooth. It's appalling.

You're much better off just buying a better amplifier. Or just buy an A07.

I guess the smiley face I put at the end did not convey the meaning.

Welcome to ASR….
…

My apologies again to the other members who are following this thread. I'm SIGMA and I don't tolerate this kind of ridiculousness in anyone. I see right through it and I call it out... You don't like it... That's on you... Be better or move along.

What does SIGMA mean?

 

[Graham849]

I guess the smiley face I put at the end did not convey the meaning.




What does SIGMA mean?

Ouch: https://www.forbes.com/sites/danidi...oscience-behind-the-sigma-male-explained/amp/

 

[Scrufboy]

You need a fan

I guess the larger issue is... We shouldn't actually need a fan. @trungdtmc is 100% right... The only reason we need a fan, heatsinks and a vented chassis is because the amplifier does such a poor job at being what it is supposed to be. It, in stock form, sounds worse than an A07 does in stock form. Is this acceptable? Is it "PRO"? So what constitutes it being "PRO"?

At the time of the posting, in regards to your reply in particular @MarcosCh, we did not have the data we have now. There were no heat issues at all and a fan was not needed. The op-amps had not been installed. Now, I don't really want to rehash this, so most of you folks can just skip reading this next part in italics.

It is a fact, that using the best thermal paste and swapping out the aluminum wafer for copper, is the most effective way to remove heat from the TPA3255 chip in this current implementation.(The original A07 had a single extruded and laser cut heatsink that was designed to not need the little aluminum wafer). This is pretty standard by way of improving the quality and efficiency of a thermal interface, and this was consistent with my statement.

*The ability to swap that aluminum wafer for copper is considered a bonus for me because it will greatly improve the performance of the heatsink. Just like using a quality, high performance thermal paste.

A fan, however, does not improve the performance of a heatsink per se. What it does is facilitate a more favorable environment where the heatsink can more effectively dissipate the heat being transfered into it. It does not change, alter or improve the thermal conductivity of the heatsink itself or the effectiveness of the thermal interface materials. The fan is not part of the thermal interface.

This was my objection at the time of posting. I hope you understand that. Perhaps I was being overly critical. However, even though I was not personally offended, the act of taking part of a statement out of context and disregarding said context is often considered offensive because the action doesn't respect or regard the concepts and principles of effective communication. I hope everyone understands this.

In truth, to be fair... The A07 Pro, out of the box, does not require any thermal interface upgrades - and as stated, this unit should not need a fan. It should not REQUIRE me, the end user, to invest any time, effort or cash to facilitate the normal intended operation of the device in stock form. However, In stock form, the changes I made should be sufficient to achieve the best possible thermal interface between the TPA3255 chip and the heatsink. So advising, at the time you did, to use a fan, I couldn't take you seriously because you seemed to ignore the facts at hand. Your two-word response came off as a poke or a jab. Again, perhaps I was being overly critical and for that you have my apologies.

This is why I challenged you though and asked you for clarification and elaboration. To put you on the spot and get you to rethink things a bit. Specifically in regards to the effectiveness of a fan that actually cannot dissipate heat from a heatsink if said heatsink is inside an enclosure where the air being moved cannot actually blow through the fins.

Only after introducing the intended op-amp set do we find these anticipated heat issues occurring with the 3 voltage regulators and that one other component. However, these extreme temps are not desirable and were unexpected. So much so that I don't think using discrete op-amps is the right way to go. In my opinion, the amplifier also needs better voltage regulators, a larger more spread out layout and a larger, fully vented case.

For those interested...

We used 7x7x9mm aluminum heatsinks from ADAfruit. We also cut and modified a 15x15x1mm pure copper heatsink plate to match the size of the aluminum wafer Aiyima used. The surfaces were prepared for bonding. We then used MG Chemicals - 8329TCM A 2 part, 45 minute work time, thermal epoxy that requires no heat curing and had the highest possible thermal conductivity available for the cure type. Specifically designed to bond different materials together. We bonded the copper to the aluminum heatsinks intended for the 12-volt regulators, waited 48 hours and then bonded these modified and standard heatsinks to the components. We then waited another 48 hours for the thermal interface material to cure.

But again... Under normal, stock operation @trungdtmc is 100% correct. We should not need to worry about heat at all. So no holes and no fans should be required. But we're now into the next phase of testing and these anticipated heat increases did in fact occur. We did not, however, expect the degree of severity we've encountered.

A correction: I initially stated that Dip8 risers would not be required on locations U8 and U16. It is now advised that if any op-amp is used that sits on a board such as a Dip8 version of an OPA1612, SS3602, etc. where the op-amps may need to be higher than the neighboring components due to their size, that you just use risers on all 5 sockets.


Remember, Aiyima came here and polled us. Asked us - this community - what they should do to make a PRO version. They, based on what we were sold in this newly released "PRO" version, was what they wanted to do and we, as a community, were effectively ignored. This is fine, and they can do whatever they want. But compared to the initial offering of the A07, this PRO unit is demonstrably inferior. It is obvious that they intended on releasing a product that they could "WOW" the mobile market with, as this A07 pro does shine as a Bluetooth amplifier. All you need is decent speakers and you will be pleased. However, when used in RCA input mode, in a chain of components, it is a night and day difference. It does not, to my ears, even come close to the original A07.

If Aiyima introduces more noise and distortion, alongside of a dull and lifeless sound through the RCA input, as compared to their Bluetooth implementation - and the amplifier is a worse performer than its predecessor. Then what are we being sold? What does "PRO" even mean? We certainly know what it's supposed to mean.

Fun Fact... The 4 nichicon caps that they advertise as part of their "upgrade" are actually an end-of-life product. This was verified when I went to several online distributors of electronic parts to look them up. This is not to say that they are bad or inferior components. I'm just pointing out that they will not be able to sustain production of this unit until Nichicon actually ships their intended replacement. Either that or Aiyima buys out all remaining stock.

It cannot be overstated - We should not have to spend more money just to achieve equalibrium with the previous product. That isn't "PRO"! A "PRO" unit is supposed to surpass its predecessor. The caps and inductors are a welcome change. But the 5 op-amp sockets indicate to me something I can only speculate and won't extend this post with those speculations.

I don't think their intention was to create an inferior product. But they definitely weren't considering that anyone would need/want to invest $400 worth of op-amps into their tiny amplifier. This was a test though. Only justifiable because I have 2 other A07's that can and will benefit from the SparkosLabs SS3602's

Ultimately, I believe, but cannot be certain just yet, that the best possible sound from this device can be achieved by using 2 SparkosLabs SS3602's in U2 and U3 and 2 Burson V6 Vivid in U8 and U9. Then either a Sparkos, OPA1612 or Burson hybrid, if it fits into the U16 location. This is purely speculation, but this opinion comes from conversations had with others who routinely combine the Sparkos & the V6 Vivid.

And sadly... This is just so it can sound as good as the original A07? With Bluetooth being the best sound this amp offers in stock form, you can clearly see who Aiyima's intended audience is.. And it surely isn't me.

IC op-amps should be relentlessly tested and evaluated so the community can come to a concensus on what the best single units are and/or combinations provide the best bang for the buck for the A07 pro. But in all honesty, this A07 pro is a pitfall of diminishing returns and should be avoided by the consumer who wants something you could consider a gem like the original A07 was and still is.

If you only need a decent, well-built Bluetooth amplifier... This is really, really decent in stock form. I'd say go for it. But if you want the next great version of a TPA3255 to put into a chain of components, thinking you can replace/upgrade from an A07: This is not for you. Not until we have enough community feedback and a comprehensive listing of op-amps that give the A07 pro a way to redeem itself and be worthy of the "PRO" designation. But again... We shouldn't have to be doing any of this at all. Buyer Beware.

 

[Scrufboy]

Ouch: https://www.forbes.com/sites/danidi...oscience-behind-the-sigma-male-explained/amp/

This is a biased article making fun of the concepts it speaks of and is not an accurate depiction of any of the characterizations.

sigma male

A more internally-focused sibling to the alpha male. While the alpha male quantifies himself on his high position in the social hierarchy, a sigma male prefers to forego the social hierarchy and need for external validation altogether and pursue internal strength instead. Essentially a "loner" or a stray man, although sigma males may have a close circle of friends and loved ones with whom they share a deep connection. The sigma male is not socially inept but simply socially disinterested. Prefers solitary activities where he doesn't have to play social politics and can simply focus on himself. The sigma male accepts that he does not need power over others as the alpha male desires, but rather needs only power to control himself and preserve his own autonomy from others.

Not to be confused with simply being an unlikeable asshole, edgelord, or misfit.