My apologies. It's homemart.usa. A link to an eBay listing for a 7297 is below.
Audio Amplifier TDA7297 Version A 15W 15W Board Dual Channel AC DC 12V New | eBay
Perhaps punters thought otherwise, and like me, are very happy with their lunch money amps?
If you had suggested that the Chinese boards sounded good, but yours were better, may have worked. If we cannot hear the shortfalls of a lunchie, how could we hear the advantages of your product?
Here, here! Or, hear, hear as the case may be!
I for one am very happy still with my $6 Lunch Money amp.
I just am not of the camp that:
1) thinks every item of stereo gear one owns needs to be modified. And, immediately so. (Not saying some things might not, but modification for modification's sake is just pointless, and I think many fall into that trap.) Spend your time listening to music and not doing pointless modifications that may even make your amp blow up, hum, sound worse, etc.
2) thinks that all things Chinese are "fake" or "junk". Where do you guys think half the parts in your car, or dishwasher, or your fancy multi-thousand dollar amps for that matter originate? From the same factories in China that's where. Anyone who can't realize that is delusional.
Yes but you still don't know what the test bed setup is made of for these chips. So you can test one from an certified supplier vs cheap ebay ones.
I think it's safe to assume that you are better off with ordering a 4$ chip from a supplier than trust the ones on ebay.
Also, regarding modifications:
Check the name of the forum you are posting
this is what we do here. Diy, that includes mods and the will to check if we can make it better.
And this kind of thinking applied to this product isn't far fetched considering that it's an ebay item made to the lowest cost possible. Heck, read some of the happenings where people got reversed connections, or reversed markings on the board. That doesn't suggest quality in designing the board, or in the surrounding parts of the chip itself. That doesn't necessarily translate into better quality ( if you mod the board), as well as it doesn't mean the board has the nicest sound in it's stock form.
We try to make it sound better.
If you wish to blab about how pointless it is to mod this board, I think it's not best to do it on diyaudio, but on other forums that don't deal with mods.
As long as we're talking about sensible and down to earth mods of course.
I think it's safe to assume that you are better off with ordering a 4$ chip from a supplier than trust the ones on ebay.
Also, regarding modifications:
Check the name of the forum you are posting
this is what we do here. Diy, that includes mods and the will to check if we can make it better.And this kind of thinking applied to this product isn't far fetched considering that it's an ebay item made to the lowest cost possible. Heck, read some of the happenings where people got reversed connections, or reversed markings on the board. That doesn't suggest quality in designing the board, or in the surrounding parts of the chip itself. That doesn't necessarily translate into better quality ( if you mod the board), as well as it doesn't mean the board has the nicest sound in it's stock form.
We try to make it sound better.
If you wish to blab about how pointless it is to mod this board, I think it's not best to do it on diyaudio, but on other forums that don't deal with mods.
As long as we're talking about sensible and down to earth mods of course.
Agreed.
AGREED. EXACTLY my point. "Sensible and down to earth." But this varies from person to person and really what should I care if a guy wants to spend $50 plus shipping and six hours modifying a perfectly good $6 amp which is God's little gift to audio? I shouldn't. And don't. Just find it amusing.
I hope I didn't "blab on" about how pointless it is to modify a board with mis-marked connections or the like. That is not pointless. And I salute the guys here, much smarter than I, who catch these sort of mistakes! Thank you!
But assuming, and not having facts about fake, junk, need to modify -- not wise.
Then again, a fool and his money (or time) are soon parted.
And agreed, this is DIY...........and of course the natural tendency is to try making/tweaking. Nothing wrong with that as long as it actually has some result.
This is getting off topic, so OK...............I agree. I will capitulate. Let's just rip everything apart because it's all fake and junk unless (and maybe EVEN if) the label says McIntosh or Krell or LFD or Devialet or Lavardin. Or, if something costs (lets' agree on a figure, over $6,000 perhaps) then let's assume there are no Chinese fake or junk parts in those rarified amps?
AGREED. EXACTLY my point. "Sensible and down to earth." But this varies from person to person and really what should I care if a guy wants to spend $50 plus shipping and six hours modifying a perfectly good $6 amp which is God's little gift to audio? I shouldn't. And don't. Just find it amusing.
I hope I didn't "blab on" about how pointless it is to modify a board with mis-marked connections or the like. That is not pointless. And I salute the guys here, much smarter than I, who catch these sort of mistakes! Thank you!
But assuming, and not having facts about fake, junk, need to modify -- not wise.
Then again, a fool and his money (or time) are soon parted.
And agreed, this is DIY...........and of course the natural tendency is to try making/tweaking. Nothing wrong with that as long as it actually has some result.
This is getting off topic, so OK...............I agree. I will capitulate. Let's just rip everything apart because it's all fake and junk unless (and maybe EVEN if) the label says McIntosh or Krell or LFD or Devialet or Lavardin. Or, if something costs (lets' agree on a figure, over $6,000 perhaps) then let's assume there are no Chinese fake or junk parts in those rarified amps?
Well, it's more about playing it safe. For 4$ a chip. That's what I did. I don't say that they are, for sure. As I don't know. I can only speculate. Based on some math, seeing the price of a chip from a trusty distributer etc.
Once again, I can't know for sure, because I don't know what to look for when testing two against each-other. The producer might have some standards regarding some characteristics that I don't know about and can't test anyway. That kind of testing might reject some chip.
Think of it this way, these chips are used in TV's or some other kind of mass market application. If the chip doesn't meet some strict characteristics, and Samsung releases hundreds of thousands of TV's with a chip that fails prematurely, it's bad for the producer of the chip.
So then you can have perfectly sounding chips, that are sold on ebay for real cheap, but they fail past 17-18V on the supply. Or some other kink..
Of course this is just speculation.
Or you can find out here that this chip sounds real nice, and then decide to build your own amp with it.
Nothing wrong with that. It's still cheap, 4$ for the chip, some FC electrolytic caps, two Wima's for signal and a pcb (that's cheap at any pcb fab house). Won't cost you a fortune, have a guaranteed original chip and can enjoy the music.
Here's my pcb design for this amp. I made it with the help of danielwritesbac, without him I couldn't have done it like this. I post it so anyone can make it and enjoy it, as I am!
Once again, I can't know for sure, because I don't know what to look for when testing two against each-other. The producer might have some standards regarding some characteristics that I don't know about and can't test anyway. That kind of testing might reject some chip.
Think of it this way, these chips are used in TV's or some other kind of mass market application. If the chip doesn't meet some strict characteristics, and Samsung releases hundreds of thousands of TV's with a chip that fails prematurely, it's bad for the producer of the chip.
So then you can have perfectly sounding chips, that are sold on ebay for real cheap, but they fail past 17-18V on the supply. Or some other kink..
Of course this is just speculation.
Or you can find out here that this chip sounds real nice, and then decide to build your own amp with it.
Nothing wrong with that. It's still cheap, 4$ for the chip, some FC electrolytic caps, two Wima's for signal and a pcb (that's cheap at any pcb fab house). Won't cost you a fortune, have a guaranteed original chip and can enjoy the music.
Here's my pcb design for this amp. I made it with the help of danielwritesbac, without him I couldn't have done it like this. I post it so anyone can make it and enjoy it, as I am!
Attachments
I agree 100%. Modding for modding sake without serious listening and then determining if its of value has many chasing an illusive holy grail of audio.
And speaking of Chinese parts... The audible quality to price point of Chinese hardware can't get much lower today. Just about ever piece of kit I buy has stood the test of time and sounds miles ahead of yesteryear stuff. Is it fake, possibly. Do I care, not one wit. Is there a lot of audio junk out there, yes! But don't let that deter anyone from having a ball playing with this stuff and being creative in implementation. This is the world we live in today - for better or worse. Personified with disposable, $6 audio amp!
One should care about the reliability of the parts.
What if your chip blows and puts a serious amount of DC into your speakers? Because the datasheet states 20VDC maximum voltage, you choose 18VDC to be safe and the chip blows?
I'm just saying that you should care. Even if the chances are slim, you should care about the parts quality.
I think it's bad advice for people getting into audio diy.
I'm not talking about audiophoolery cables and capacitors, but decent parts from an engineering point of view.
We all love cheap with nice SQ but in reality you get what you pay for.
What if your chip blows and puts a serious amount of DC into your speakers? Because the datasheet states 20VDC maximum voltage, you choose 18VDC to be safe and the chip blows?
I'm just saying that you should care. Even if the chances are slim, you should care about the parts quality.
I think it's bad advice for people getting into audio diy.
I'm not talking about audiophoolery cables and capacitors, but decent parts from an engineering point of view.
We all love cheap with nice SQ but in reality you get what you pay for.
No, not really.
I just used whatever I had laying around that fit the footprint.
The diodes are to220 package, I think I used MUR860 or something like that. You can use any diode that fits the power requirements. Calculate the maximum amount of current that is going to go through them, and see what power they will dissipate for 0.6V drop on them.
Also choose the power supply knowing that 0.6V will drop on them. You could omit the LEDs, they are only as an indicator for each power supply rail.
Lots of discussion on the big caps, you can choose from 470uF to as large as it fits on the footprint.
The rest of the values are from the datasheet, the small cap should be a 10uF I think and the resistors...I don't remember. Look up the datasheet for tda7297 and you should see them.
The board can accommodate a single supply (you must install links instead of the diodes, double supply for each channel (you have pads after the diodes) or you can install one supply with the diodes to separate the rails.
Input is near the NP capacitors, you also have two pin width options for the input caps.
Signal input ground is right next to the chip pin.
I just used whatever I had laying around that fit the footprint.
The diodes are to220 package, I think I used MUR860 or something like that. You can use any diode that fits the power requirements. Calculate the maximum amount of current that is going to go through them, and see what power they will dissipate for 0.6V drop on them.
Also choose the power supply knowing that 0.6V will drop on them. You could omit the LEDs, they are only as an indicator for each power supply rail.
Lots of discussion on the big caps, you can choose from 470uF to as large as it fits on the footprint.
The rest of the values are from the datasheet, the small cap should be a 10uF I think and the resistors...I don't remember. Look up the datasheet for tda7297 and you should see them.
The board can accommodate a single supply (you must install links instead of the diodes, double supply for each channel (you have pads after the diodes) or you can install one supply with the diodes to separate the rails.
Input is near the NP capacitors, you also have two pin width options for the input caps.
Signal input ground is right next to the chip pin.
Sorry, I meant to say film caps when I said non-polarized. I didn't try any NP electrolytic cap so I can't comment on that.
You have to look at the statistical failure rate. Even though my sampling pool is small, it 100% for me, and I haven't had any component part fail, something blowup, or magic smoke since buying a lot of PCBs, parts and other kit from my Chinese suppliers in the past 5 years. You do get what you pay for, and I never suggested I purchase everything at rock bottom prices or from AliExpress, or other such places where quality may be in serious question.
I do pay attention to the descriptions and brand of components manufacturers say they use. Using a reliable seller on the bay does have its advantages. Caveat Emptor and shop wisely.
Please don't act like a victim among victims. I shared a link to another site for my project. Just because someone didn't want to spend the money doesn't mean they didn't see the value. Value, at that, isn't yours to determine for others; and the price directly reflected the value Mouser charges you BTW. You seem predicated on the idea that someone's being forcrd to be the victim of buying something they don't need. Preposterous. You've never heard it. You're not unlike someone who had never sailed or left their homeland claiming the earth is flat and it's just silly otherwise as there's no value to a difference from where you stand.
I never said the Chinese boards didn't sound good with a few tweaks. In fact I made a little guide to making one sound good. Prior to some changes they had qualities in sound I wanted, but in stock form where not up to snuff as something I'd personally listen too. That's why I spent over a year testing and gaining a rather clear understanding of the chip. Information that I clearly share if it comes up.
So please, again? Stop pestering me for your problem. I don't care that you didn't have $200, didn't see the value, or that you like to be content. Clearly not all posts here are about you and no one, not even you, is a victim of anything like you are trying to make it out to be.
You have to look at the statistical failure rate. Even though my sampling pool is small, it 100% for me, and I haven't had any component part fail, something blowup, or magic smoke since buying a lot of PCBs, parts and other kit from my Chinese suppliers in the past 5 years. You do get what you pay for, and I never suggested I purchase everything at rock bottom prices or from AliExpress, or other such places where quality may be in serious question.
It is pointless to say "from China" or "from Asia". Most of the electronics in the world come from that area. That is not to say that they are good or bad. The only differentiator between good or bad electronics is actually the standard of the producing factory. The work itself cannot be labeled as good or bad. Work is work, the people that are actually building the parts/products are doing what they are told to do, and they get their paycheck.
What matters most, is who is telling them what to do. If the standards are high, you get nice electronic gear (see Apple for example). It is made in China, but it's made to a certain standard.
Both legit and reject and clone chips (whatever chip, not this one) are all made there. Only that the ones that are legit, have high standards, the ones that are faked have the lowest standard and it's a bit of a gamble with the "cloned" ones (meaning the ones that the producer bought the plans for). You can still find transistors like 2sc2240 produced by CDIL (India) under the name CSC2240.
That doesn't guarantee that it has the same output quality as a NOS 2sc2240. Even if they followed the original building plan.
So it's a bit wrong to refer to bad chips as chips bought from China, or Asia, as most chips are made there, the good ones as well.
The problem here is if the chips used in the ebay boards are class A chips from an authorised ST factory or substandard chips that have been tested as working but didn't cut the mustard for top applications.
Which eBay board did Destroyer OS mod?
Hi everyone:
This thread is now many, many pages long. Would someone please clarify for me, which exactly which eBay seller's board did Destroyer OS mod?
I'm asking because I'd like to try those mods if I buy some , and because audiocircle.com is down right now. I have no idea how long it will be down (with no offense meant to audiocircle).
Hi everyone:
This thread is now many, many pages long. Would someone please clarify for me, which exactly which eBay seller's board did Destroyer OS mod?
I'm asking because I'd like to try those mods if I buy some , and because audiocircle.com is down right now. I have no idea how long it will be down (with no offense meant to audiocircle).
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