I have a dac with transformers... i tried on tripath but it did not work....
Now is connected to your amp...
I wonder if it works without caps...
I know guy who has output caps on his preamp, so he does not use input caps usually. Sometimes different combinations of caps if he tries input caps then the amp doesnt want to turn on. Sadly I,do not have full details on his preamp. So for whatever his problem is, I cannot be sure if it would be yours. The chips is very good at protection. So if you try it, it'll be great for everyone to know.
Last time i tried with tripath i almost blown my speakers...
I will try with some old cheap speakers..
Hello folsom and all music lovers i would like to share that yesterday i put your amp against a 100watss amp.(non feedback circuit with sanken transistors) in my house.
Dispite more power from that amp, the little "big" folsom has the same dynamics.... and is more cleaner in the highs and more musical engaging...the sound is superb, is so clean. Is a pure pleasure to listen.
Every cable or mod i do in my dac is revealed by the amp.
Thanks for your impressive work! And good luck for the new project.
In meantime i will try to connect transformers to the amp without caps to see how it does. I will report later.
Nuno
Dispite more power from that amp, the little "big" folsom has the same dynamics.... and is more cleaner in the highs and more musical engaging...the sound is superb, is so clean. Is a pure pleasure to listen.
Every cable or mod i do in my dac is revealed by the amp.
Thanks for your impressive work! And good luck for the new project.
In meantime i will try to connect transformers to the amp without caps to see how it does. I will report later.
Nuno
But I am talking about the chip and amp in general. As long as the chip is ok, and the feedback loop is working correctly, there may not be any problems.
What protections are in place if the chip or a switching transistor fails? Is there protection for the speakers?
From what I have gleened from reading, have steps been taken to dampen any extremely high frequency spikes (in microsecond range) on the chip, or switching transistors, to prevent destruction? Even high frequency electrolytic capacitors are not necessarily protection.
I want to be assured there will be no unintended consequences to my speakers.
Thanks.
pos
The feedback is internal. If the chip fails then nothing goes to speakers. If either of the transistors on the board go bad then the chip doesn't get power.
You can always add a speaker protection circuit if you want, after the amp. I don't think it's necessary at all.
The chip can't really do anything high frequency. It rolls off fast.
You can always add a speaker protection circuit if you want, after the amp. I don't think it's necessary at all.
The chip can't really do anything high frequency. It rolls off fast.
If the chip or switching transistors fail, nothing happens? If the internal feedback fails, nothing happens? I find that difficult to believe. From Tripath
Is this a copy/general design that all companies use, down to the parts, or a specific design from the individual/company? Do you have a schematic I can see?
pos
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I've already shown you the PDF for the 7297. There is nothing between the 7297 and the speaker outputs. I don't have the exact schematic of the inside of the chip.
Every chip failure to date has been just 0 sound.
I don't really know very many amps without actual speaker protection on outputs, fill your criteria.
Every chip failure to date has been just 0 sound.
I don't really know very many amps without actual speaker protection on outputs, fill your criteria.
Is that earlier in the string somewhere or another link? Would you provide the link for .pdf? I must have missed it.
Do I have the right amp, as 7297 specs say dual 15 watt AB, not tripath. Is there another that is 60 watt and 100 watt?
What is the frequency response +/- say 0,1db or whatever figure is given?
thanks
pos
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Any direct coupled amplifier needs a speaker protection circuit as semiconductors can fail (ask any Tripath owner) which will likely result in a burned woofer.
Extra good reason is that a speaker protection circuit generally costs less than a woofer. You will never know what the end user will do with the device, some might use it for tweeters in an active system. There protection certainly is necessary.
I admit that it does not happen often but when it happens it is almost always fatal for the speaker. Most speaker protection circuits also prevent the plop at power on/off which is not luxury but simply good design.
When preamp and power amp are DC coupled it is good design practice to put either input caps in the power amp or output caps in the preamp (not in both as seen in many commercial devices). Any error in the preamp will not end up in the same magic smoke then.
Extra good reason is that a speaker protection circuit generally costs less than a woofer. You will never know what the end user will do with the device, some might use it for tweeters in an active system. There protection certainly is necessary.
I admit that it does not happen often but when it happens it is almost always fatal for the speaker. Most speaker protection circuits also prevent the plop at power on/off which is not luxury but simply good design.
When preamp and power amp are DC coupled it is good design practice to put either input caps in the power amp or output caps in the preamp (not in both as seen in many commercial devices). Any error in the preamp will not end up in the same magic smoke then.
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That is what I thought, catastrophic problems can result. Thanks for your reply Jean-Paul. Much appreciated.
pos
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People here use to have good loudspeakers that often cost a few bucks. Certainly in such cases one should use speaker protection regardless of the type of amplifier used.
I have many years experience with repairing high end stuff that also did not need speaker protection according the manufacturer. It is electronic stuff so it can die when you least expect it taking a woofer to the grave too. I have once repaired an amp that was only 2 x 10W that had a slow servo and was best left on (better according the manufacturer). When a few power hiccups occurred the slow servo caused both woofers to burn and there was no one at home. I have repaired a Tripath amp that failed when the owner switched on a vacuum cleaner! The internal protection did not save the woofers.
It is simple good design practice to incorporate a separate speaker protection circuit. Since the trend is to buy the cheapest amps possible in China the designs more and more lack muting/anti-plop/protection circuits. This is not good design practice easily proven when the first one fails when connected to 500 $ speakers. It is not strange that 6$ amps lacks a protection circuit when connected to 10$ loudspeakers but with audio enthousiasts chances are likely that better more expensive speakers are used. This calls for better protection. Don't copy the cost cutting/omitting as done with cheap chinese amps.
TDA7297 can deliver 2A and that really is enough to damage stuff. Internal protection sounds nice but cutting off by an external circuit when DC is put out by the amplifier is way safer. Even if thousands have been sold and things go OK it is no guarantee that a few won't fail in 5 years.
I have many years experience with repairing high end stuff that also did not need speaker protection according the manufacturer. It is electronic stuff so it can die when you least expect it taking a woofer to the grave too. I have once repaired an amp that was only 2 x 10W that had a slow servo and was best left on (better according the manufacturer). When a few power hiccups occurred the slow servo caused both woofers to burn and there was no one at home. I have repaired a Tripath amp that failed when the owner switched on a vacuum cleaner! The internal protection did not save the woofers.
It is simple good design practice to incorporate a separate speaker protection circuit. Since the trend is to buy the cheapest amps possible in China the designs more and more lack muting/anti-plop/protection circuits. This is not good design practice easily proven when the first one fails when connected to 500 $ speakers. It is not strange that 6$ amps lacks a protection circuit when connected to 10$ loudspeakers but with audio enthousiasts chances are likely that better more expensive speakers are used. This calls for better protection. Don't copy the cost cutting/omitting as done with cheap chinese amps.
TDA7297 can deliver 2A and that really is enough to damage stuff. Internal protection sounds nice but cutting off by an external circuit when DC is put out by the amplifier is way safer. Even if thousands have been sold and things go OK it is no guarantee that a few won't fail in 5 years.
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I remember those cheap RCA/Philips amp chips back in the 70s and forward, that would blow and take the speaker. I thought those types were gone, but evidently not. I'll pass.
keep on truckin
joe
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This isn't a chip from the 70's. The speaker protection thus far has worked superbly when users have done silly things. Typically the amp won't even die, it just turns off a channel or two, and can come back on if the problem gets fixed.
But I thank you for believing I can do better protection board that STmicro.
But I thank you for believing I can do better protection board that STmicro.
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