This is why you should ask Tilear owner vs Green owner so you can check yourself. Bushellj has the green version, you might get his opinion.
The boards are basically identical. That said the newer board does not have the same silk screen with all the component values !! It is only the choice of components that differ between the boards. The green boards appear to be populated with cheaper capacitors (The big Elna Caps remain). The Inductor for the Power Supply has been reduced from 22uH to 10uH (even on some of the Black boards).
The main advantage of the TPA2351 based Amplifiers over the TPA3255 is that because they run out lower voltages the Power Supply Capacitors can be three times the value and still fit in these small cases. Given the choice between the Aiyima A04 (TPA3251) and Aiyima A07 (TPA3255) the A04 TPA3251 model would appear to be the better one for most domestic situations where a few 10's of Watts is more than adequate.
What’s disappointing is that every advertisement for the Aiyima TPA3251 2.0 amp has photos of the black PCB rather than the revised green one. The sellers should accurately represent the products they sell rather than use the “bait and switch” sales method. The AliExpress listing specifically states:
“Fever grade water filter with two 3000uf filters up to 6000uf; use red ring inductor, high frequency characteristics, LC filter network with S-iemens fever capacitor, E-LNA red robe audio capacitor, T-K Audio series coupling capacitor.”
I would be interested in knowing if anyone has purchased the amp based on this description and received the green board unit without the specified Elna Starget and Toshin Kogyo UTSP input capacitors as advertised.
In any case, do not confuse this with another Aiyima TPA3251 amp that includes Bluetooth wireless connectivity. In other forums, owners have complained about noise.
I bought the Aiyima TPA3251 2.0 amp out of curiosity since it is relatively inexpensive, and with some minor modifications that I have previously mentioned, the amp (black PCB is only one I’ve tried), this is really impressive. I am still waiting for Allo to introduce their TPA3255 amp. cdsgames, a user on these forums, had mentioned that Allo was working on development of a TPA3255 amp that could compete with the Hypex Ncore Class D amps, but I haven’t heard anything new on this.
“Fever grade water filter with two 3000uf filters up to 6000uf; use red ring inductor, high frequency characteristics, LC filter network with S-iemens fever capacitor, E-LNA red robe audio capacitor, T-K Audio series coupling capacitor.”
I would be interested in knowing if anyone has purchased the amp based on this description and received the green board unit without the specified Elna Starget and Toshin Kogyo UTSP input capacitors as advertised.
In any case, do not confuse this with another Aiyima TPA3251 amp that includes Bluetooth wireless connectivity. In other forums, owners have complained about noise.
I bought the Aiyima TPA3251 2.0 amp out of curiosity since it is relatively inexpensive, and with some minor modifications that I have previously mentioned, the amp (black PCB is only one I’ve tried), this is really impressive. I am still waiting for Allo to introduce their TPA3255 amp. cdsgames, a user on these forums, had mentioned that Allo was working on development of a TPA3255 amp that could compete with the Hypex Ncore Class D amps, but I haven’t heard anything new on this.
hi Amigo,
I hope you re doing well ? Do you have some inputs about the Audio Science Review opportunity ?
By the way, did you read the review of my New TPA3255, that is a very good alternative to the Aiyima TPA3251, with 4 Op Amps and tone control checkout :
TPA3255 - all about DIY, Discussion, Design etc.
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So this is what I got with the Green PCB :-
New Circuit Board inside - No longer branded “Tilear" but otherwise looks similar. No version numbers on the PCB !!
From the look of the PCB compared with the TPA3255 they appear to be from the same design house as most of the tracks are identical. The only major difference is the Switch (Double Pole) and the extra circuitry in the TPA3251 model adjacent to the switch which I am guessing is the Anti Pop stuff.
Main Power Supply Caps are 2 x Elna 3,000uF 35V. Interesting that this is 3x bigger than the TPA3255 model (2 x 1,000uF 50V) but lower voltage of course.
12 Volt Power Supply Caps are mostly Rubicon 470uF 16Volt
Signal Input to Op-Amps are TK "Audio" Caps 10uF 50V
Signal Output from Op-Amps to TPA3251 are Nichicon (gold coloured) 10uF 16Volt.
So the caps, other than the main Elna ones, are all different from the original board.
Every batch of boards appears to have different components - But that is what makes buying stuff from China so exiting - You have no idea what your going to get until it arrives !!
I am appalled about the hibreze amp I believed was reviewed by daniboun. There is a grounded intlet with no ground. Class ii does not need ground but the power supply has to be double insulated and has some creapage regulations that I believe are not followed in this case. Violation of design and safety principles and laws that are clear to the naked eye. If that is what you can see, what kind of corners have they cut on the product?
In the USA hundreds of people die of electrical hazzard and millions of dollars are lost to electrical fires. When a
company is willing to neglect the safety of their customers are endanger their lives for a cost savings of just some cents, why anyone assumes that you are getting original components?
Remarks ( changing the sepcs rating), rejects (selling factory discarded components), refurbs (selling repaired as new), salvaged ( removed from uses equipment), and counterfeits ( fake product with original labels) are rampant scams on the electronic industry. Relabeling components is a great business. If I wrap my caps with elna stickers I can make 10-20 per cent more profit. And this is normal in the industry. That is the easiest way to cut costs while charging a premium.
During the early 2000s a generation of electronics failed due to faulty Chinese cap since a dielectric formula was stolen from Japan and improperly implemented.
I work in the it industry and fake Asus motherboard and Intel network cards are common, with logos, serial numbers, stickers and packing that looks like the original. Even the USA armed forces, a big electronics buyer, had to set procedures to make sure non original components will not creep into the supply lines. Imagine a missile failing due to a fake underrated power regulator
So my point is: how can you believe that you are getting original nichicon, elna and ti parts when the manufacturer saves 3 cents on a ground nut and bolt and 2 cents on a boards that are too small to comply with ac main creepage regulations.
Bad safety design is a simptom of an inferior design and a hazzard that can injure you or cost your life. We should not even discuss or recommend equipment of sellers that disregard our lives. This is a hobby and it should not be life threatening.
In the USA hundreds of people die of electrical hazzard and millions of dollars are lost to electrical fires. When a
company is willing to neglect the safety of their customers are endanger their lives for a cost savings of just some cents, why anyone assumes that you are getting original components?
Remarks ( changing the sepcs rating), rejects (selling factory discarded components), refurbs (selling repaired as new), salvaged ( removed from uses equipment), and counterfeits ( fake product with original labels) are rampant scams on the electronic industry. Relabeling components is a great business. If I wrap my caps with elna stickers I can make 10-20 per cent more profit. And this is normal in the industry. That is the easiest way to cut costs while charging a premium.
During the early 2000s a generation of electronics failed due to faulty Chinese cap since a dielectric formula was stolen from Japan and improperly implemented.
I work in the it industry and fake Asus motherboard and Intel network cards are common, with logos, serial numbers, stickers and packing that looks like the original. Even the USA armed forces, a big electronics buyer, had to set procedures to make sure non original components will not creep into the supply lines. Imagine a missile failing due to a fake underrated power regulator
So my point is: how can you believe that you are getting original nichicon, elna and ti parts when the manufacturer saves 3 cents on a ground nut and bolt and 2 cents on a boards that are too small to comply with ac main creepage regulations.
Bad safety design is a simptom of an inferior design and a hazzard that can injure you or cost your life. We should not even discuss or recommend equipment of sellers that disregard our lives. This is a hobby and it should not be life threatening.
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You are absolutely right !
This is what I have already been told. This is easy to correct, see what has been suggested in previous comments. I perfectly agree.
This is the bad point here and need to be checked before using.
it is not a reason to be silent or not to share my impressions! on the contrary my friend! people are now aware, I rather rendered a good service I think!
++ points :
Just concerning the sound quality and the good points.
After a 10 hours listening test now, the amplifier is ABSOLUTELY nice.
This is my 5th amp based on TPA32XX and I think is among the best I listened to. The Tone control with the OPA1656 switched is very efficient and I can shape my sound as I want now.
The Amplifier is using 63V Panasonic (FC series) caps. No hiss, dead silent amplifier, this is a really good point too. The enclosure is well designed.
Other good point, you can totally remove the PSU with 4 screws and the Amplifier board is easy to remove as well, so perfect for custom / update.
The Aiyima TPA3251 blew me away and this one has all the qualities of Aiyima with a few more possibilities. This is why I keep on saying this is a good alternative to the Aiyima TPA3251 with a TPA3255 chip instead + Anti Pop at startup and it's appreciated for me.
some other pictures :
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By all means Daniboun, if you buy it, review it. I would be very careful and personally sell or stop using the unit since even with the ground fixed, the board design and the position of the mains is unfixable. As an electrical engineer it is my opinion and advice, which you are free to follow or not, to discontinue the use of any device with such shoddy engineering practices. Even at 50 usd, if it burns your house it is not a good value.
Not the most qualified to explain this, but creepage regulations represent a protections against an arching type fenomenon where a spark can travel in a non conductive material like a copper free area of the board. That can lead to electrical fires. So, you leave an specified distance in certain area , such power main or interfaces to external long cable ( a sensor or button on a control systems) to prevent hazzard.
My point of not future testing was directed to HiBrez. I am not confident on their ability to design and integrate devices with high voltage. Their dc low voltage units may be great, but as a community I believe we should not support them with sales unless they make a commitment to out safety vs their profit. This is a public forum and as such they are free to join the conversation and prove me wrong. That would make me happy as it will show that they have acted in good faith fixing an issue.
Not the most qualified to explain this, but creepage regulations represent a protections against an arching type fenomenon where a spark can travel in a non conductive material like a copper free area of the board. That can lead to electrical fires. So, you leave an specified distance in certain area , such power main or interfaces to external long cable ( a sensor or button on a control systems) to prevent hazzard.
My point of not future testing was directed to HiBrez. I am not confident on their ability to design and integrate devices with high voltage. Their dc low voltage units may be great, but as a community I believe we should not support them with sales unless they make a commitment to out safety vs their profit. This is a public forum and as such they are free to join the conversation and prove me wrong. That would make me happy as it will show that they have acted in good faith fixing an issue.
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Thank you for the advice ... we have a proverb in France which said: "An informed man is worth two." (Un homme averti en vaut deux)
I guess you think the same about this External PSU ? :
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This looks better. At least the module is grounded. No ground on the case and power connection may be too close. Also no regulatory stickers.
Stickers may mean something, ( the unit was approved by a regulatory inspection) or nothing ( fake stickers). But lack of them means for sure that they have not bother with certification.
Stickers may mean something, ( the unit was approved by a regulatory inspection) or nothing ( fake stickers). But lack of them means for sure that they have not bother with certification.
Uw Daniboun. I love the French saying, true and awesome.
Two of mine. Decent manufacturer with real certification, fused inside and sealed. They are designed for led signs to be outside and to operate 24 7 365 at full power. Even used they have a great value.
Two of mine. Decent manufacturer with real certification, fused inside and sealed. They are designed for led signs to be outside and to operate 24 7 365 at full power. Even used they have a great value.
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The Silver Aiyima 3251 amp I received from Amazon today is identical to the Black one from a few weeks ago .
Both are marked A04 on the front and have a neat and clean black Tilear pcb board marked rev. 2.0
A really fine sounding amp and doubly so at the price.
I ordered a 32 volt Power brick from Aiyama and am currently using a 24 volt Dayton brick to power the amp
Both are marked A04 on the front and have a neat and clean black Tilear pcb board marked rev. 2.0
A really fine sounding amp and doubly so at the price.
I ordered a 32 volt Power brick from Aiyama and am currently using a 24 volt Dayton brick to power the amp
