I think a good habit to get into, is to actualy check places like the National Semiconductor site, to see who their distributor in your area is, and then use it. Then you get the real thing from them directly.
In fact, I find it easier now, to order samples directly from these dealers than from National itself. (at least faster, and free)
Destroyer, we would love to hear what you think about the chipamp, I know you will probably be embabrased to admit haveing built one infront of your solid state friends... lol, but you do have a very valued opinion on this site.
Don't need to give us an audiomagazine review, just a simple "I liked it", or" no, I like something else better..."
Cheers
In fact, I find it easier now, to order samples directly from these dealers than from National itself. (at least faster, and free)
Destroyer, we would love to hear what you think about the chipamp, I know you will probably be embabrased to admit haveing built one infront of your solid state friends... lol, but you do have a very valued opinion on this site.
Don't need to give us an audiomagazine review, just a simple "I liked it", or" no, I like something else better..."
Cheers
R1,R2
Hmmmmm, I've just cut my 22k resistor that I put in, as I thought it was in the wrong place. I was following the page three diagram,(but wired it incorrectly, or so I thought). I am making a P2P LM3875. So I take it that the 220R is in front of the 22K then?...........Oh well better to this correct now. Thanks for bringing this up.
Hmmmmm, I've just cut my 22k resistor that I put in, as I thought it was in the wrong place. I was following the page three diagram,(but wired it incorrectly, or so I thought). I am making a P2P LM3875. So I take it that the 220R is in front of the 22K then?...........Oh well better to this correct now. Thanks for bringing this up.
I constructed the pretty red board, Brian i think is the one that produces
The wonderfull board....but i found 680 ohms from Pin 8 to ground!
As i am completely neurotic related those things that have not the value....R1, R2 and R3....this turns me so pixel, that i start to dislike deeply the circuit.....my own neurotical, Psichotical, Esquizofrenic problem...i hate those complications....that you have to find a paper to discover what is R1 value...and them to fix in the R1 place that is marked in the board!!!
Why not to put the value directly printed in the board?..... well.... each crazy one with their own crazy things!
So, i found a resistor from Pin 8 to ground..... this is not so nice!..... and may be my problem related those R1, R2, R3....grrrrrrrr!...i hate those things...why complicate so simple things!
And my sound was alike battery radio..... where is the bass?.... i had to increase 20 decibels to perceive the bass....sub bass was impossible to listen.
This way i search the National aplications and i perceive that they cutted the bass because of the case size....impossible to dissipate continuous 50 watts of power... so i understood why the small condenser into the feedback line, the inverted input, that is the same as the second differential transistor in a standard discrete amplifier.
Well....i changed values, as i was having 2 watts when the amplifier was reproducing 15 hertz!!!
Now i have 25 watts in this frequency...and will increase the 1000uf condenser to have a completely flat amplifier from 5 hertz to 20 Kilohertz.
Negative!,the amplifier is not bassy now, it is flat!....having bass entering, it reproduces, without increase nothing or decrease the treble...it is nice,but cannot face some discrete!...sorry!...no chance!
Now, the Chip is sounding alike a big amplifier...do not know if will survive, as National made that not for mistake....hehe....they are avoiding that we send the unit to space!
Try if you want guys...i do not recomend, in the reality, my modifications are a foolish, but the sound result is not!
Now amplifier is flat!...the chip is LM3875, with metal case, with negative voltage there!
It is early in the morning, i cannot play too much loud, it may appear problems related the maximum current protection, and this i will check tomorrow!....but sounding as a battery radio, with that damn mid ranges and trebles only, is too much for my ears!...aaaaagh!
regards,
Carlos
The wonderfull board....but i found 680 ohms from Pin 8 to ground!
As i am completely neurotic related those things that have not the value....R1, R2 and R3....this turns me so pixel, that i start to dislike deeply the circuit.....my own neurotical, Psichotical, Esquizofrenic problem...i hate those complications....that you have to find a paper to discover what is R1 value...and them to fix in the R1 place that is marked in the board!!!
Why not to put the value directly printed in the board?..... well.... each crazy one with their own crazy things!
So, i found a resistor from Pin 8 to ground..... this is not so nice!..... and may be my problem related those R1, R2, R3....grrrrrrrr!...i hate those things...why complicate so simple things!
And my sound was alike battery radio..... where is the bass?.... i had to increase 20 decibels to perceive the bass....sub bass was impossible to listen.
This way i search the National aplications and i perceive that they cutted the bass because of the case size....impossible to dissipate continuous 50 watts of power... so i understood why the small condenser into the feedback line, the inverted input, that is the same as the second differential transistor in a standard discrete amplifier.
Well....i changed values, as i was having 2 watts when the amplifier was reproducing 15 hertz!!!
Now i have 25 watts in this frequency...and will increase the 1000uf condenser to have a completely flat amplifier from 5 hertz to 20 Kilohertz.
Negative!,the amplifier is not bassy now, it is flat!....having bass entering, it reproduces, without increase nothing or decrease the treble...it is nice,but cannot face some discrete!...sorry!...no chance!
Now, the Chip is sounding alike a big amplifier...do not know if will survive, as National made that not for mistake....hehe....they are avoiding that we send the unit to space!
Try if you want guys...i do not recomend, in the reality, my modifications are a foolish, but the sound result is not!
Now amplifier is flat!...the chip is LM3875, with metal case, with negative voltage there!
It is early in the morning, i cannot play too much loud, it may appear problems related the maximum current protection, and this i will check tomorrow!....but sounding as a battery radio, with that damn mid ranges and trebles only, is too much for my ears!...aaaaagh!
regards,
Carlos
Attachments
Let it be...ridiculous...with a Jaca fruit and a Watermellow around the neck
With monokini....and dancing shaking the hum.
ahahahaha.... be happy man...it is sounding in those ridiculous speaker in my ridiculous house playing ridiculous musics in a ridiculous volume.
I am watching 1 cicle per second moving my speaker...ridiculous movement that is turning me ridiculously happy!
All right my..........friend!
ahahahahhaa!
Carlos
With monokini....and dancing shaking the hum.
ahahahaha.... be happy man...it is sounding in those ridiculous speaker in my ridiculous house playing ridiculous musics in a ridiculous volume.
I am watching 1 cicle per second moving my speaker...ridiculous movement that is turning me ridiculously happy!
All right my..........friend!
ahahahahhaa!
Carlos
Carlos, 1,000~1500uf is a trend introduced by the original 25W Gaincard, and the typical 'gainclone' is a copy of that.
What I meant is that this capacitance is anywhere near enough to move most speakers, and then the amp sounds bad.
I was referring to the ridiculous capacitance (1,000uf), nothing more.
What I meant is that this capacitance is anywhere near enough to move most speakers, and then the amp sounds bad.
I was referring to the ridiculous capacitance (1,000uf), nothing more.
Well boys, i am the intruder, from another honney Comb i entered here and turn you
Scandalalized with me.
I am just a poor bee....bzzzzzzz!....that needed some informs about flowers positioning, so i came here at other honeycomb, and off course the "soldiers" will surround me, as i am an stranger, the invader, danger!!!
I good friend sent me those chips, and much more than that, made the kindness to send me wonderfull red boards from Brian, and i was following instructions in PDF from Mr. Daniels.
Well guys, Mr. Daniel is one of the "sacred monsters", one of the famous "gurús" that made experiences and constructed something special, with fine wood and interesting materials, including more value of craftsman and quality to the design.
Meu amigo Carlão FM, my dear friend Big Charlie FM, is another famous guy that is snubberiziertzsen you all, producing movement, good ideas and instructing new guys to construct...another famous gurú too.
Each one of them, those gurús, and may have more than those, with their own ideas related the way to make the best possible.
I came here, in first moment to have instructions,as i was confused with those references....R1, R2...and i could not find fast.... the values that matched those references...also i post my own idea about those "more complicated methods" than just print the value over the board....my personnal point of view, as this is one other step to construction...translate R1 in resistor ohms values.
The guys that sent me those Chips, for free and direct from Australia, was very kind and curious to listen what i think about the sound quality, as i made the same question to him, and that was the reason that moved him to send me the chips to test.
As i love AKSA, and i love Symassym and GEM and some other amplifiers he also apreciate, he was curious to see if my opinion about LM3875 is the same opinion as he has.
I constructed and found that was some mistake in my construction, that i installed wrong resistor (R3) directly to ground....but this could be a "decision" to produce some amount of gain and not to compensate losses in bass tones..... very low deep tones...something that is clever, to avoid too much heat dissipation and burn the small chip, or even start some protection that can destroy dinamics or even produce some sub product that could be annoying.
I do not like, any amplifier, beeing Chip, not chip, discrete, mixed, inverted, non inverted, tubes, fets or all those together that cannot reproduce, because of adjustments, very low deep bass...alike 10 hertz, that we do not listen but we feel the vibration, and 25 hertz that we can listen and also feel the vibrations.
I perceived that the circuit, the way it was, could not produce enougth power in those frequencies,and them i increase the feedback electrolitic condenser, the same way we do in the second differential transistor in discrete constructions...the second transistor is connected to output, and receive the feedback, having also that compensation, a resistor in series with an electrolitic condenser, this last one connected to ground, having normally values from 47uf to 470 uF.
So i was going increasing it, till i reach 3300uf, and this was too much!....them i reduced to 1000uf, and i have suspections that 470uf could be good to reproduce 5 hertz.....it is nice to see the speaker moving slowly, 5 times each second....or even slower, and receiving more than 13 volts rms in it's coil....giving me guarantee that it will be able to reproduce some "warble" sound that is normally used in very low frequencies in movies, to give us the idea of power, and fear when is recorded in some image of submarines under battle or in some terror movie scenes...beeing that deep bass that produces the vibrations, that make us feel fear.
And i made that, to say better things about the amplifier to the one that sent me, and informing here to cooperate, but i think you already know those things a more than million ears ago.
No, i will not inform more things about, only to the one that gave me the chip...no evaluation...it is nice, of course, but comparative details not...do not want to start a "nuclear war" here.
Well.....Big Fat Charlie, the dirty ridiculous invader, saying that apreciate you all very much, including Carlos FM, that is telling that the size of condenser is ridiculous, beeing to much big and ugly.....will be happy and free of me that i am running as fast as i can, to be very distant from this place, as i know the "nature" rules very well..... another bee, from other Honeycomb, entering here and "rebolando muito"...shaking too much the body, and make too much noise!...ahahahahah!...will be in hard trouble!.
Bye guys!, now i am crossing the Saturn rings..... going to Andromeda, my home town.
regards,
Carlos
Scandalalized with me.
I am just a poor bee....bzzzzzzz!....that needed some informs about flowers positioning, so i came here at other honeycomb, and off course the "soldiers" will surround me, as i am an stranger, the invader, danger!!!
I good friend sent me those chips, and much more than that, made the kindness to send me wonderfull red boards from Brian, and i was following instructions in PDF from Mr. Daniels.
Well guys, Mr. Daniel is one of the "sacred monsters", one of the famous "gurús" that made experiences and constructed something special, with fine wood and interesting materials, including more value of craftsman and quality to the design.
Meu amigo Carlão FM, my dear friend Big Charlie FM, is another famous guy that is snubberiziertzsen you all, producing movement, good ideas and instructing new guys to construct...another famous gurú too.
Each one of them, those gurús, and may have more than those, with their own ideas related the way to make the best possible.
I came here, in first moment to have instructions,as i was confused with those references....R1, R2...and i could not find fast.... the values that matched those references...also i post my own idea about those "more complicated methods" than just print the value over the board....my personnal point of view, as this is one other step to construction...translate R1 in resistor ohms values.
The guys that sent me those Chips, for free and direct from Australia, was very kind and curious to listen what i think about the sound quality, as i made the same question to him, and that was the reason that moved him to send me the chips to test.
As i love AKSA, and i love Symassym and GEM and some other amplifiers he also apreciate, he was curious to see if my opinion about LM3875 is the same opinion as he has.
I constructed and found that was some mistake in my construction, that i installed wrong resistor (R3) directly to ground....but this could be a "decision" to produce some amount of gain and not to compensate losses in bass tones..... very low deep tones...something that is clever, to avoid too much heat dissipation and burn the small chip, or even start some protection that can destroy dinamics or even produce some sub product that could be annoying.
I do not like, any amplifier, beeing Chip, not chip, discrete, mixed, inverted, non inverted, tubes, fets or all those together that cannot reproduce, because of adjustments, very low deep bass...alike 10 hertz, that we do not listen but we feel the vibration, and 25 hertz that we can listen and also feel the vibrations.
I perceived that the circuit, the way it was, could not produce enougth power in those frequencies,and them i increase the feedback electrolitic condenser, the same way we do in the second differential transistor in discrete constructions...the second transistor is connected to output, and receive the feedback, having also that compensation, a resistor in series with an electrolitic condenser, this last one connected to ground, having normally values from 47uf to 470 uF.
So i was going increasing it, till i reach 3300uf, and this was too much!....them i reduced to 1000uf, and i have suspections that 470uf could be good to reproduce 5 hertz.....it is nice to see the speaker moving slowly, 5 times each second....or even slower, and receiving more than 13 volts rms in it's coil....giving me guarantee that it will be able to reproduce some "warble" sound that is normally used in very low frequencies in movies, to give us the idea of power, and fear when is recorded in some image of submarines under battle or in some terror movie scenes...beeing that deep bass that produces the vibrations, that make us feel fear.
And i made that, to say better things about the amplifier to the one that sent me, and informing here to cooperate, but i think you already know those things a more than million ears ago.
No, i will not inform more things about, only to the one that gave me the chip...no evaluation...it is nice, of course, but comparative details not...do not want to start a "nuclear war" here.
Well.....Big Fat Charlie, the dirty ridiculous invader, saying that apreciate you all very much, including Carlos FM, that is telling that the size of condenser is ridiculous, beeing to much big and ugly.....will be happy and free of me that i am running as fast as i can, to be very distant from this place, as i know the "nature" rules very well..... another bee, from other Honeycomb, entering here and "rebolando muito"...shaking too much the body, and make too much noise!...ahahahahah!...will be in hard trouble!.
Bye guys!, now i am crossing the Saturn rings..... going to Andromeda, my home town.
regards,
Carlos
Re: Well boys, i am the intruder, from another honney Comb i entered here and turn you
Carlos, I just said that 1,000~1,500uf caps on the PSU is not enough to produce decent bass.
I don't know if you urderstood me.
You seem to be changing other things on the circuit, while the problem is the PSU.
Whatever...
I was just trying to help, but you don't want any help.
Your feedback is not important, at least for me, I know what these chips can do, and they can sound very different depending on the way you use them. PSU is very important.
It is up to you if you want to share your results and impressions of the amp you built, of course.
If you want, try this PSU. It's easy to adapt to what you have already built.
PS: I don't expect any feedback, so relax!
destroyer X said:
Carlos, I just said that 1,000~1,500uf caps on the PSU is not enough to produce decent bass.
I don't know if you urderstood me.
You seem to be changing other things on the circuit, while the problem is the PSU.
Whatever...
I was just trying to help, but you don't want any help.
Your feedback is not important, at least for me, I know what these chips can do, and they can sound very different depending on the way you use them. PSU is very important.
It is up to you if you want to share your results and impressions of the amp you built, of course.
If you want, try this PSU. It's easy to adapt to what you have already built.
PS: I don't expect any feedback, so relax!
Attachments
Well guys, the visit here delay much more than i hope for, and i thank you all:
Steenoe
Peter Daniel
Greg Erskine - close personal friend
Mod-Evil - close personal friend
SSS
Wintermute- close personal friend
Dariusku
Jay
Carlos FM
Nordic
Enzedone
Ouroboros
I thank you, all of you, that were helpfull.
FM, i saved your images related amplifier and supply, thank you.
I have to inform that my bench supply, used for testing purposes are using 40000uf plus 40000uf, having resistor to drain slowly when power is off, and having bypass 100N condensers to be a low impedance patch to DC supply output line oscilations that may come from amplifier board.
The Chip amplifier, this LM3875 is using 4700uf each rail directly over the board, near the chip, distance less than 1 inch.
In parallell with those electrolitic condensers there are 100N as i always used since i was a very young boy starting those constructions 45 to 46 years ago.
In this special case, i installed a second filtering board having 4700 plus 4700uf with 100N capacitors of course, very near the main board...why i did that!...because i am a maniac and a little bit crazy, as i think that 10000uf will be much more than enougth for this amplifier, even working with 4 ohms loads.
90000uf is beeing used...the 1000uf is used in series with the 680 ohms resistor that Peter Daniel is using....the intention was to increase low end bass...not because i am doing better, or because was not correct the way Peter Daniel do, or Carlos FM do...just because i am crazy for bass, i prefered this way, and i decided to make this way to have the chance to compare with others that can reproduce, without losses, 5 hertz sinusoidal steady tones without too much loss of power..... A to B comparison will show clearly the advantage of some amplifier that had more strength in the bass frequencies...so...not to be unfair, i made it..the Chip amplifier, to have the same bass capabilities as my other amplifiers.
Ouroboros, thank you, really, there are not 1000uf in my supply, only in my second differential feedback internal transistor...the inverted chip's input.
Mine is better?....NO!...it has more bass strengh only!...maybe more distortions or other sub product!
Guys, i am sorry, but i am without threads to follow in Solid State amplifiers..... and also will be interesting to me not to follow another thread, as i have 23 amplifiers to construct in my list, and this is to be made before Christmas, so, i will unsubscribe here, as i already finished my research, the Chip amplifier sound good, but there are another that sounds good too.
I will show you the other one, you may know it, maybe there are many threads about it.
And after that, i will disappear from forum to construct my amplifiers.
Will not answer this thread, as i will be out from Forum...this one, and other ones...doing things, soldering, constructing, and giving some rest to my fingers typing and tongue talking...now will solder!...DO THINGS!
Regards, bye, farewell and thank you all.
Carlos
Steenoe
Peter Daniel
Greg Erskine - close personal friend
Mod-Evil - close personal friend
SSS
Wintermute- close personal friend
Dariusku
Jay
Carlos FM
Nordic
Enzedone
Ouroboros
I thank you, all of you, that were helpfull.
FM, i saved your images related amplifier and supply, thank you.
I have to inform that my bench supply, used for testing purposes are using 40000uf plus 40000uf, having resistor to drain slowly when power is off, and having bypass 100N condensers to be a low impedance patch to DC supply output line oscilations that may come from amplifier board.
The Chip amplifier, this LM3875 is using 4700uf each rail directly over the board, near the chip, distance less than 1 inch.
In parallell with those electrolitic condensers there are 100N as i always used since i was a very young boy starting those constructions 45 to 46 years ago.
In this special case, i installed a second filtering board having 4700 plus 4700uf with 100N capacitors of course, very near the main board...why i did that!...because i am a maniac and a little bit crazy, as i think that 10000uf will be much more than enougth for this amplifier, even working with 4 ohms loads.
90000uf is beeing used...the 1000uf is used in series with the 680 ohms resistor that Peter Daniel is using....the intention was to increase low end bass...not because i am doing better, or because was not correct the way Peter Daniel do, or Carlos FM do...just because i am crazy for bass, i prefered this way, and i decided to make this way to have the chance to compare with others that can reproduce, without losses, 5 hertz sinusoidal steady tones without too much loss of power..... A to B comparison will show clearly the advantage of some amplifier that had more strength in the bass frequencies...so...not to be unfair, i made it..the Chip amplifier, to have the same bass capabilities as my other amplifiers.
Ouroboros, thank you, really, there are not 1000uf in my supply, only in my second differential feedback internal transistor...the inverted chip's input.
Mine is better?....NO!...it has more bass strengh only!...maybe more distortions or other sub product!
Guys, i am sorry, but i am without threads to follow in Solid State amplifiers..... and also will be interesting to me not to follow another thread, as i have 23 amplifiers to construct in my list, and this is to be made before Christmas, so, i will unsubscribe here, as i already finished my research, the Chip amplifier sound good, but there are another that sounds good too.
I will show you the other one, you may know it, maybe there are many threads about it.
And after that, i will disappear from forum to construct my amplifiers.
Will not answer this thread, as i will be out from Forum...this one, and other ones...doing things, soldering, constructing, and giving some rest to my fingers typing and tongue talking...now will solder!...DO THINGS!
Regards, bye, farewell and thank you all.
Carlos
Attachments
I think so Greg....tony, wintermute told me that you wrote this message to me
thank you Tony.
Well, it is possible that i sent you to Spam....as i made some modifications and i did that with a lot of people.
The way i have to fix that, is to receive something in the bulk mail and pointed the guy as not beeing Spam.
I could not find the Spam list.....i use to make those mistakes.
I am sorry Greg, i was thinking you computer was damaged.
Please, insist in contact me...using directly mail and forum mail services.
regards,
Carlos
thank you Tony.
Well, it is possible that i sent you to Spam....as i made some modifications and i did that with a lot of people.
The way i have to fix that, is to receive something in the bulk mail and pointed the guy as not beeing Spam.
I could not find the Spam list.....i use to make those mistakes.
I am sorry Greg, i was thinking you computer was damaged.
Please, insist in contact me...using directly mail and forum mail services.
regards,
Carlos
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