45 watts of sand-cast wirewounds BUNDLED together
As in bundled so that they touch eachother, like two smacking teabags ?

As in bundled so that they touch eachother, like two smacking teabags ?![]()
eww
I'm a tea-seholic, mea maxima culpa.
I bought these square tea-bags in GB last spring, attached to eachother as a string in the box.
If i put two side-attached bags in a pot they stick like folding leaves and it takes long for the tea to reach prime time, i have to put them in one by one.
Power resistors are like little heatsinks, they need plenty clearance to cool properly.
Bundle them together and their temperature will skyrocket, despite having plenty power reserve.
I bought these square tea-bags in GB last spring, attached to eachother as a string in the box.
If i put two side-attached bags in a pot they stick like folding leaves and it takes long for the tea to reach prime time, i have to put them in one by one.
Power resistors are like little heatsinks, they need plenty clearance to cool properly.
Bundle them together and their temperature will skyrocket, despite having plenty power reserve.
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An amp that will drive, if I recall, "2 Ohms without burping" probably is not having trouble with speakers or cables. I wish I knew that answer but my first thing to eliminate as a problem would be the speakers/cables.
Uriah
Uriah
Depending on wether Bluewater has wired or not the limiters.
In the second case, an intermittent short circuit could be lethal.
I am thinking about a thin strand of copper at one end of the cable for instance.
He said he replaced the channel which burnt again.
So, i immagine the cause is external.
...Better to ask Bluewater if he uses limiters.
In the second case, an intermittent short circuit could be lethal.
I am thinking about a thin strand of copper at one end of the cable for instance.
He said he replaced the channel which burnt again.
So, i immagine the cause is external.
...Better to ask Bluewater if he uses limiters.
It is a little off topic isn't it 🙂
🙂
24 Volt supply, with 16 volts quiescent across 16 ohms.
I=V/R so that's 16/16 which is 1 amp.
Watts = I*V so that is 1*16 which is 16 watts.
That's under no signal conditions.
Worst case is the FET turning on and putting 24 volts less the drain source saturation voltage.
Lets go worst case and say 24 volts.
Using the above that's 36 watts.
The amp is AC coupled at the input however so that's not going to happen.
You need to choose a resistor (data sheets !) that will dissipate around 20 watts (preferably a non inductive component too) in the conditions you require ie free space, or attached to a heatsink where you have calculated the temperature rise etc and know it is within the operating limits of the resistor.
🙂 And my somewhat "unkind" last comment.
If we take the power out (headphones) as say 20mw and the power input of the amp as 24 watts, then powerout/powerin * 100 gives an efficiency of 0.083%
Draw your own conclusions on that one 🙂
I was hoping for some help there.
🙂
24 Volt supply, with 16 volts quiescent across 16 ohms.
I=V/R so that's 16/16 which is 1 amp.
Watts = I*V so that is 1*16 which is 16 watts.
That's under no signal conditions.
Worst case is the FET turning on and putting 24 volts less the drain source saturation voltage.
Lets go worst case and say 24 volts.
Using the above that's 36 watts.
The amp is AC coupled at the input however so that's not going to happen.
You need to choose a resistor (data sheets !) that will dissipate around 20 watts (preferably a non inductive component too) in the conditions you require ie free space, or attached to a heatsink where you have calculated the temperature rise etc and know it is within the operating limits of the resistor.
🙂 And my somewhat "unkind" last comment.
If we take the power out (headphones) as say 20mw and the power input of the amp as 24 watts, then powerout/powerin * 100 gives an efficiency of 0.083%
Draw your own conclusions on that one 🙂
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If we take the power out (headphones) as say 20mw and the power input of the amp as 24 watts, then powerout/powerin * 100 gives an efficiency of 0.083%
Draw your own conclusions on that one 🙂
As a long as it sounds divine, who cares about the lowish efficiency? 🙂
Don't tell the Greens, they might kill you! 😛As a long as it sounds divine, who cares about the lowish efficiency? 🙂
A few amps at this size wont make any difference
Use of aluminium etc and shipping of various components around the world is much worse
But still very small in the big picture
One person taking a single flight trip might use the same energy as all of us use in a whole year
One person taking frequent flight trips may in a single year use as much a you use in a lifetime
Or try looking at how much your flat screen TV consume
And how many people have power consuming flat screens
If you look at the amount of components involved, possible recycling etc Im sure you will get a completely different outcome
Use of aluminium etc and shipping of various components around the world is much worse
But still very small in the big picture
One person taking a single flight trip might use the same energy as all of us use in a whole year
One person taking frequent flight trips may in a single year use as much a you use in a lifetime
Or try looking at how much your flat screen TV consume
And how many people have power consuming flat screens
If you look at the amount of components involved, possible recycling etc Im sure you will get a completely different outcome
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Please don't tell me you've given up on class A amps.The planet.
Not at all, but there is no need to be extravagant.
I am shure Teabag built it as a training exercise, not to really use it.
I am shure Teabag built it as a training exercise, not to really use it.
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It is not the planet...it is the human beings that inhabit the planet. 🙂
The planet shall endure...
Regards,
M
The planet shall endure...
Regards,
M
.........
The planet shall endure...
Regards,
M
Hmm.. Mother earth will one day flare up at her children like in the movie 2012... Btw, how many believe in such thingy? it sounds too convincing to me with all the ancient thingy pointing to one common time.
I'm surprised Pass Labs hasn't been shut down by the state of California where they've just banned energy wasting televisions.
Hmm.. Mother earth will one day flare up at her children like in the movie 2012... Btw, how many believe in such thingy? it sounds too convincing to me with all the ancient thingy pointing to one common time.
I saw that flick on tuesday...Quite a rockus. Besides, where am I going to come up with a billion euros?
I've finished up and started working on some new projects with my time off lately. My original headamp variation doesn't stay stable, so I tried this, just to get an idea. As much as I listen, I dont think either will cause too much global warming, but glad you fellas are concerned.
Throwing in a question..
I am using this DAC http://www.diyaudio.com/forums/digital-line-level/137976-experience-diy-dac-148.html#post1979788connected to my F5,but when i take de signal from the LL1517 i get oschillation,workes fine from the opampoutput.
But The F5 gets realy hot when taking it from the LL1517,it sounds fine thow.
I´ve been trying to lower the bandwith on the F5 with a 10pf or 20pf cap paralell to the input of F5,I runs a little cooler but not enough as without the DAC connected,how big cap can I add without lowering the bandwith to much?Or any other suggestions?
I am using this DAC http://www.diyaudio.com/forums/digital-line-level/137976-experience-diy-dac-148.html#post1979788connected to my F5,but when i take de signal from the LL1517 i get oschillation,workes fine from the opampoutput.
But The F5 gets realy hot when taking it from the LL1517,it sounds fine thow.
I´ve been trying to lower the bandwith on the F5 with a 10pf or 20pf cap paralell to the input of F5,I runs a little cooler but not enough as without the DAC connected,how big cap can I add without lowering the bandwith to much?Or any other suggestions?
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