That's great, Mark. Except the fact that the real LM3886es were made in Greenock. That's why there was a shake-up of the LM3886 product line (discontinuance of LM3875, LM3876, LM4780, etc.) recently as TI closed the Greenock fab. Future LM3886es will be made elsewhere. My guess is South Portland, ME but time will tell.
Exactly. You save the monetary equivalent of a cup of coffee on a $x00 project.
The "LM3886" I received with my XY kit did contain a die that was marked LM3886, so it's probably a higher quality counterfeit IC. Maybe a test reject that doesn't meet specs. Maybe it "fell off a truck" and was rebadged. Who knows. When you buy counterfeit ICs, there is no guarantee that you'll get what you pay for or get the same type of counterfeit IC as ordered previously. Personally, I'd rather drink one fewer cups of coffee and put that money towards the purchase of a genuine LM3886.
Tom
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I've led you to water. You've refused to drink. You're free to believe what you believe.
National did not have a fab in China. No National process, such as the one the LM3886 was made on, was ever transferred to a Chinese sub-contractor.
I worked from 2005 to 2011 for National Semiconductor and stayed on until 2015 after the TI acquisition. I think I have a pretty good idea of their operations and where the fabs and assembly plants were located because I dealt with them directly.
National did occasionally use subcontractors, such as TSMC, but at no point was a National process transferred to a subcontractor. The LM3886 is made on a National process. Probably VIP3.
Tom
National did not have a fab in China. No National process, such as the one the LM3886 was made on, was ever transferred to a Chinese sub-contractor.
I worked from 2005 to 2011 for National Semiconductor and stayed on until 2015 after the TI acquisition. I think I have a pretty good idea of their operations and where the fabs and assembly plants were located because I dealt with them directly.
National did occasionally use subcontractors, such as TSMC, but at no point was a National process transferred to a subcontractor. The LM3886 is made on a National process. Probably VIP3.
Tom
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But my ebay vendor promised the chips were genuine...
So, I'm another XY kit purchaser. I don't have a lot of skin in the game. Just looking to rebuild a Crown D60, and build a couple pairs of active speakers... or have a couple of workbench play-amps.
I'm new to attaching pix here, so here goes. If the pic is not clear, I got LM3886TF chips which would pass cursory inspection: acceptable "fit and finish":, laser-etched markings... but the date/lot/mfg code is: 3BA2NRUE3
Maybe I'm missing something, but that just does not grok with any format I've found on the TI website.
??
Please help me out here if I'm missing something obvious.
I'm thinking, the 2 amp boards and psu board for $6 are still an ok deal *if* you're willing and able to modify connections between ground pour sections, add appropriate (Theile, Zobel, noise) compensation networks, etc. to get something that looks marginally prettier than a p2p dead bug lashup.
Or just buy Toms 3886DR boards, if you actually place any value on your time... and support legitimate, honest vendors.
I can see both sides of that approach, but ebay vendors selling (fake/counterfeit/bogus/grey/substandard) parts as the real thing just rubs me in the wrong way.
Fodder.
-Peter
So, I'm another XY kit purchaser. I don't have a lot of skin in the game. Just looking to rebuild a Crown D60, and build a couple pairs of active speakers... or have a couple of workbench play-amps.
I'm new to attaching pix here, so here goes. If the pic is not clear, I got LM3886TF chips which would pass cursory inspection: acceptable "fit and finish":, laser-etched markings... but the date/lot/mfg code is: 3BA2NRUE3
Maybe I'm missing something, but that just does not grok with any format I've found on the TI website.
??
Please help me out here if I'm missing something obvious.
I'm thinking, the 2 amp boards and psu board for $6 are still an ok deal *if* you're willing and able to modify connections between ground pour sections, add appropriate (Theile, Zobel, noise) compensation networks, etc. to get something that looks marginally prettier than a p2p dead bug lashup.
Or just buy Toms 3886DR boards, if you actually place any value on your time... and support legitimate, honest vendors.
I can see both sides of that approach, but ebay vendors selling (fake/counterfeit/bogus/grey/substandard) parts as the real thing just rubs me in the wrong way.
Fodder.
-Peter
Attachments
Looks like a new production (after TI acquisition) genuine LM3886.
Should you wish to reproduce the data sheet performance (i.e. get what you paid for) I suggest using my boards. I'm a bit partial to those, I do admit. 🙂
Tom
Should you wish to reproduce the data sheet performance (i.e. get what you paid for) I suggest using my boards. I'm a bit partial to those, I do admit. 🙂
Tom
Hm, that is an interesting picture🙂
To the neysayers:
I would of course not buy a 100$ case and 100$ powersupply and put in two xy kits!
But to restore an old amp that might work or feeding 10 cheap speaker elements with their own amp and a common powersupply, the cost of the amp module plays a role.
The future looks bright for solutions where only the most linear and low distortion part of a (cheap?) speaker element is used. Digital freqency deviding is getting cheap and C0G caps makes analog filters both small and high presision.
Then you need a lot of cheap, low noise amp modules with enough overhead for peaks, but they only need to handle low crest factor.
So spending a little time measuring and selecting components, like in the old transistor days, can be worth it. (If you find a nice batch of factory rejects)
The pricees I refer to is ebay 1.5$ counterfeits/old stock vs 6$ genuines.
(Maybe the penny pinching is to extreem if 10 chips is needed. If only 2 are needed to fix a friends amp I choose the xy because I'm lazy and he is ignorant;-)
To the neysayers:
I would of course not buy a 100$ case and 100$ powersupply and put in two xy kits!
But to restore an old amp that might work or feeding 10 cheap speaker elements with their own amp and a common powersupply, the cost of the amp module plays a role.
The future looks bright for solutions where only the most linear and low distortion part of a (cheap?) speaker element is used. Digital freqency deviding is getting cheap and C0G caps makes analog filters both small and high presision.
Then you need a lot of cheap, low noise amp modules with enough overhead for peaks, but they only need to handle low crest factor.
So spending a little time measuring and selecting components, like in the old transistor days, can be worth it. (If you find a nice batch of factory rejects)
The pricees I refer to is ebay 1.5$ counterfeits/old stock vs 6$ genuines.
(Maybe the penny pinching is to extreem if 10 chips is needed. If only 2 are needed to fix a friends amp I choose the xy because I'm lazy and he is ignorant;-)
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It's not, it's a bloody hard way to earn a few more pennies. I know as I did this. By the time you work it all out, answering emails, posting on forums, helping people out etc you would actually earn more per hour stacking shelves.
Yep. On top of that, there're the cost of prototyping, test equipment, tools, supplies, taxes, licenses, etc.
If money is your main objective, working for an actual employer is far more lucrative.
Tom
So you are not in it for the money then? Sorry, just thought the amount of time you spend promoting your $39 board on here, and all this hysteria you have created about fake chips, not forgetting the crap XY boards that need hacking (your wording....spin)
I work for myself and TBH find that more lucrative, despite your preachings!
Not the case, thought this was a DIY forum. TBH I just find $39 a pop for a pcb hard to swallow, and as TOMCR says make your own choice. Equally sounding amps, be they XY, chipamp, audiosector or ebay specials can be had as complete kit for the same money (and with real chips).
I know there is a lot of "gullibility" in the world of ready made HiFi, looks like the DIY arena is going the same route!
There is a lot of crap out there, I'm more than happy to pay the cost of entry for a well engineered product. Tom has the credentials and it shows in his designs. I doubt he is trying to compete with cheep, poorly engineered and supported rubbish.
Luckily there is choice at many different price points, if you don't like Tom's price point find another. No need to complain or try to justify your position.
Luckily there is choice at many different price points, if you don't like Tom's price point find another. No need to complain or try to justify your position.
$39 for a PCB is expensive, but that is NOT what you are paying for. You are paying for a board that, provided you use the BOM supplied GUARANTEES YOU the promised performance, with direct email support (In English and at least one other European language) if you get into trouble.
If that is too much, and I realise for some it is, or if you believe that spec sheet performance is better than you need, there are boards that cost less delivered than seems feasible, with no measurements done, and backup if you are lucky. DIY exists at all levels, from some who want to roll their own to some who just want it to work. It's a great time for DIY despite all the doom and gloom stories about it being dead.
Instead of complaining raise a glass and cheer that there is choice and the information required to make an informed decision.
Then kick back and spin some choons, after all its entertainment 🙂
If that is too much, and I realise for some it is, or if you believe that spec sheet performance is better than you need, there are boards that cost less delivered than seems feasible, with no measurements done, and backup if you are lucky. DIY exists at all levels, from some who want to roll their own to some who just want it to work. It's a great time for DIY despite all the doom and gloom stories about it being dead.
Instead of complaining raise a glass and cheer that there is choice and the information required to make an informed decision.
Then kick back and spin some choons, after all its entertainment 🙂
I've built Tom's Modulus 86 Amp... Overall experience? Tom's documentation is excellent, response to queries also very quick; no trouble in getting the parts in the BOM. And yes, the amp sounds good too. 😀
+1 🙂
+1 🙂