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Old 9th November 2005, 07:58 PM   #31
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Join Date: Feb 2004
Location: Recife - Brasil Northeast
Default 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 Carlăo 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 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 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 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 is nice, of course, but comparative details 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.


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Old 9th November 2005, 08:25 PM   #32
Join Date: Mar 2003
Location: Lisbon, Portugal
Default Re: Well boys, i am the intruder, from another honney Comb i entered here and turn you

Originally posted by destroyer X
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.....

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.

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!
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Old 9th November 2005, 08:28 PM   #33
Join Date: Mar 2003
Location: Lisbon, Portugal
Default More work for a slow day

And this, if you want to try.
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Old 10th November 2005, 08:58 AM   #34
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Join Date: Feb 2004
Location: Recife - Brasil Northeast
Default Well guys, the visit here delay much more than i hope for, and i thank you all:

Peter Daniel
Greg Erskine - close personal friend
Mod-Evil - close personal friend
Wintermute- close personal friend
Carlos FM

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 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! 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 will solder!...DO THINGS!

Regards, bye, farewell and thank you all.

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Old 10th November 2005, 09:00 AM   #35
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Location: Recife - Brasil Northeast
Default The second image..i am going....bye guys!

I already gone........bye!

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Old 10th November 2005, 07:06 PM   #36
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Location: Sydney/Australia
Hi Carlos,

Good to see you having some fun with the chipamps.

BTW: I think my emails are not reaching you.
Greg Erskine
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Old 10th November 2005, 10:24 PM   #37
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Join Date: Feb 2004
Location: Recife - Brasil Northeast
Default 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 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.


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