Of course they know when they purchase what they do.
Re market potential...How many devices world wide are using LME49720 vs 5532? Guess the potential is not comparable plus it is perhaps easier to get closer to the old 5532 perf avoiding too much trouble in case it doesn't exactly work as intented?
Who knows... anyway, nothing to do with TPA3251
Re market potential...How many devices world wide are using LME49720 vs 5532? Guess the potential is not comparable plus it is perhaps easier to get closer to the old 5532 perf avoiding too much trouble in case it doesn't exactly work as intented?
Who knows... anyway, nothing to do with TPA3251
I upgraded the opams since the $1 dollar upgrade seemed logical for me. I also retouched all solder joints. The Aiyimas are a good implementation and someone with hand soldering skills better than mine can replace some components, such as supply caps and chokes. My main complain with the unit is the low quality output connectors. But that will require a recasing of the amp.
The Aiyima units are very well engineered and even if some of the components have some "funkiness" the result is very impressive in absolute terms and in cost/performance. The TI audio chips are very impressive.
The market of "fakes" is kind of funny. Some copies are just simply crap, some may be really good. Sometimes is a competitor sanded and relabeled product, a leftover stock, that "changes" brand. Sometimes is the same IC mask that someone stole or production rejects. So no all fakes are bad. Just look at the B&C DE250, there are many copies, clones and counterfeit out there, some of them, like the diysoundgroup.com, match or outperform the original.
A smart engineer that may use "affordable" parts; can test and sample multiple parts and sources and decide which ones have the better real use and performance, and buy them. The result can be good if good attention, testing and benchmarking is used.
The Aiyima units are very well engineered and even if some of the components have some "funkiness" the result is very impressive in absolute terms and in cost/performance. The TI audio chips are very impressive.
The market of "fakes" is kind of funny. Some copies are just simply crap, some may be really good. Sometimes is a competitor sanded and relabeled product, a leftover stock, that "changes" brand. Sometimes is the same IC mask that someone stole or production rejects. So no all fakes are bad. Just look at the B&C DE250, there are many copies, clones and counterfeit out there, some of them, like the diysoundgroup.com, match or outperform the original.
A smart engineer that may use "affordable" parts; can test and sample multiple parts and sources and decide which ones have the better real use and performance, and buy them. The result can be good if good attention, testing and benchmarking is used.
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Thank you for posting the pics of the different 5532 chips , it reminded me to get off my duff and get my order in to Mouser for a handful of the 5532's from TI.
The issue here is you need to understand how the Chinese manufacturing market works. Typically the person or people who design the product are not the same people who do the manufacturing or source the components.
You submit a design to a potential manufacturer and they give you a quote to build it. Once they have the order they go out and source the PCB and components, build the board / Amplifier and you get back whatever they have built !
The problem is most of the manufacturers just build the products with whatever components they have on the shelf or with something that vaguely resembles the spec you provided ! Hence the difference between batches of the same product - Exactly what we are now seeing with the Aiyima A04 product which appears to be cost reduced with every new batch. No Quality Control !
I used to work for a major semiconductor company. Let’s just take memory chips as an example. We would manufacture a few 10s of thousands of memory chips. These would be tested at the end of the production line and the ones that met 100% of the specification would be appropriately labelled and sold to customers.
What was left would end up in a rejects bin !! Now with memory chips you only needed to have one cell that failed the test and the chip ended up in the reject bin.
Now some intelligent manufacturers of consumer grade equipment would design their products so the board would accept say a 32Mb chip but the application only needed 16Mb. They would then have a jumper to select the working half of the chip !!
We would sell the whole bin of thousands of partially working chips for next to nothing. The manufacturer would retest the chips to see which half was still functional and set the jumper on the board so the chip could still be used.
The same was true of many other semiconductor products. Most of the stuff that doesn’t make the grade when tested ends being sold at low cost to toy manufacturers or other cheap consumer products where quality is way down the priority list.
I am guessing that a lot of these components may well get re-labelled and end up back in the supply chain for other mainstream products where the Quality Control
Is either lacking or non-existent.
I have two Aiyima Amplifiers and one set of Op-Amps appear to be genuine And the other are completely different and I assume are fake. Certainly replacing them with Op-Amps from Mouser made and enormous difference but at the time I didn’t make a record of which Op-Amps were installed originally. I think the earlier one had the real chips but the last Aiyima A04 I purchased, replacing the Op-Amps made a difference even an old man like me could appreciate !!
Hi amigos,
Take an OPA1656 and you will be assured that they are not fake and they perform really well with the Aiyima TPA3251 (Tilear rev 2.1).
It’s a bit of a reductive thought I know )
Take an OPA1656 and you will be assured that they are not fake and they perform really well with the Aiyima TPA3251 (Tilear rev 2.1).
It’s a bit of a reductive thought I know )
Dani,
any link to get genuine pre- soldered OPA1656 in DIP format?
Ho about LM4562/LME49720 or OPA2134 in Aiyima TPA3251?
please suggest
thanks
any link to get genuine pre- soldered OPA1656 in DIP format?
Ho about LM4562/LME49720 or OPA2134 in Aiyima TPA3251?
please suggest
thanks
Hi Saran.
I have some OPA1656 on adapters in the UK - Same ones I provided to Danny !! Chips sourced from Mouser (TI main Distributor) and assembled by me on to adapters with gold plated turned pins - not the cheap square pins !!
Normal postage - No Tracking included in cost below. If you want Tracking then it would be an extra £7 on top for any quantity. Assume you only want a couple.
I have been selling them for £14 UK Pounds each including shipping.
Seems a bit odd shipping chips to Singapore - Bit like selling sand to the Middle East !
James.
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Danny,
thanks for the links.
Bushellj,
much thanks for your offer also.
I am running my A04 with original NE5532AP from RS components for now.
Plan to swap & test with LM4562 first.
then I will try to test with OPA1656.
thanks for the links.
Bushellj,
much thanks for your offer also.
I am running my A04 with original NE5532AP from RS components for now.
Plan to swap & test with LM4562 first.
then I will try to test with OPA1656.
If and when the heat sink is removed, you'll see the Tilear Rev 2.1 logo on the green board.
Rob43
is 2200 uf an issue?
I saw some posts ago the Ti toll to calculate the correct combination of chokes and cap to match the output impedance. Not familiar with the tool, but anyone versed may elaborate if the capacitance decrease is a no go ( upgrade) and what would be the choicest capacitance (3200 uf, maybe 50 V as 35V may be too close for a 36V power supply).
I saw some posts ago the Ti toll to calculate the correct combination of chokes and cap to match the output impedance. Not familiar with the tool, but anyone versed may elaborate if the capacitance decrease is a no go ( upgrade) and what would be the choicest capacitance (3200 uf, maybe 50 V as 35V may be too close for a 36V power supply).
The main issue I ran into with this was trying to find a very high quality "Audio Grade" cap that was roughly ~3000 to 3900 uF at 50v, I couldn't find what I wanted because everything was just to big. So I chose a 3300 uF 35v, even this is on the large size considering the space limitations of this amp ...
When using a 35v cap at about ~32 volts, you're running it at ~92% of it's rated ability. While this is close, I consider it acceptable.
Rob43
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Maybe, haven't dismantled yet. but all the ELNA gone and no more 3000uF. But same price of amp.
can you please care to share the 3300uf/35v cap part number?
Doc,
The ones inside TPA3250 FX502s pro is Dia 16x25mm height (max already)
Inside Aiyima A04 is also Dia 16x25mm (current ARC audio 2200uF), but Dia 18x25mm possible (old Default ELNA 3000uF).
Just curious to know, what model Rob bought for this 3300uF/35V.
thanks
The ones inside TPA3250 FX502s pro is Dia 16x25mm height (max already)
Inside Aiyima A04 is also Dia 16x25mm (current ARC audio 2200uF), but Dia 18x25mm possible (old Default ELNA 3000uF).
Just curious to know, what model Rob bought for this 3300uF/35V.
thanks