I am sorry folks...i have checked my amplifier and anything wrong with the series
resistances...the smell came from another place...i do not know where..maybe speaker, maybe modem, maybe computer.... speaker crossover use resistances...i found smell of something burning.....maybe speaker as it is underrated to my power amplifier output....and i was driving the amplifier really hard listening Sidney (Australia) Symphonic Orchestra yesterday.
Once i found this resistance warm..almost hot when i was testing the amplifier using steady tone generator, square wave and full power...and i decide to increase it in the Dx Blame blue boards, the MKII and also the Supercharged and the Dx Blame ES and Dx Blame ST already have suggested higher watt/size to these rail resistances.
To use higher watt...half watt or even one watt, as modern resistances are very small..well..this cannot be bad anyway..also to use a diode as i said can be done without troubles..and this cannot produce any harm to your amplifier.
I am uploading video showing my PC amplifier inside...and anything burned or smelling there.
I am sorry.... i was confused...i thougth was the resistances...but they are fine.
Soon i will post here the link to the video that i am already uploading to youtube.
regards,
Carlos
resistances...the smell came from another place...i do not know where..maybe speaker, maybe modem, maybe computer.... speaker crossover use resistances...i found smell of something burning.....maybe speaker as it is underrated to my power amplifier output....and i was driving the amplifier really hard listening Sidney (Australia) Symphonic Orchestra yesterday.
Once i found this resistance warm..almost hot when i was testing the amplifier using steady tone generator, square wave and full power...and i decide to increase it in the Dx Blame blue boards, the MKII and also the Supercharged and the Dx Blame ES and Dx Blame ST already have suggested higher watt/size to these rail resistances.
To use higher watt...half watt or even one watt, as modern resistances are very small..well..this cannot be bad anyway..also to use a diode as i said can be done without troubles..and this cannot produce any harm to your amplifier.
I am uploading video showing my PC amplifier inside...and anything burned or smelling there.
I am sorry.... i was confused...i thougth was the resistances...but they are fine.
Soon i will post here the link to the video that i am already uploading to youtube.
regards,
Carlos
Attachments
Was a stupid theory mine.... anything wrong with the resistances
I have imagined it should be burning (theory)..... but real world use to be something different..and anything toasted there...here is the video:
YouTube - Everything all right with the Dx Blame ST
regards,
Carlos
I have imagined it should be burning (theory)..... but real world use to be something different..and anything toasted there...here is the video:
YouTube - Everything all right with the Dx Blame ST
regards,
Carlos
Yes, they can read the posts.
They have no idea about our relative experiences other than what is written in our posts.
Myself and Andrew only wan't the best for you ... 🙂 I stopped using the proposed current limiting device (your opinions influenced that) on my VAS and went back to just that collector resistor that is being discussed. I even removed it to see if my BE device emitter resistor/device would heat up with abuse. It did , but did not burn. The sound is the same with or without the resistor , but the devices in question do not get as warm with it. Even with abuse ,all 1/4 or 1/2w resistors in my BX/AX are barely warm. These are so similar to your amp... same 1-2ma LTP - 7-8ma VAS currents , why do yours behave different?? I agree w/ Andrew , something else is "Afoot". 😀
OS
OS
I see Ostripper.... i do believe your good intentions to help
People can include the colector resistance if they want.... please inform the lowest possible value you have used and resulted fine... are you sure sounded the same?...say....have you tested this deeply?...listening for several hours with stop in between auditions? (ear adjust...ear plus brain adjusts).... have you tried several different musical programs....i have perceived differences in sonics... sounded less musical and more stérile with the resistance...but really protects a lot.
Be very carefull about what you say and suggest..so..check it three times..as people may try, may compare and if they perceive differences will not trust you anymore..then you can say thousands of truth and no one will give you attention.....we fight a lot, and for long time, to obtain their confidence....if we make ONE MISTAKE.....sadly they loose confidence in that easy way.... so...."this is better"...is something that should be said with a lot of care
To include the resistance people will have to cut colector lead to insert a series resistance or to produce a cut in the board copper track...and this is something terrible to a very developed board with a design that started by Todd Johnson...a hard work he has made..and several others developed the board too... Omar/Rudi.... also Mitchel, also Zharmo....well.... a lot of guys... seems Alexmm has made too....it is not a good idea to cut tracks and to insert parts this way.
I have decided to avoid the mess.... to increase associated resistances, the transistor power, also using heatsinks to drivers.
The main problem that you have not understood...or i have not used a good english to communicate with U2, Ostripper and AndrewT, is misuse..bad use.... torture.... the dangerous user.
I repeat...let's see if this time (third and last try) you capture what happened:
The amplifier was made and adjusted to produce full power with 750 milivolts PEAK into the input.... i had guys using 8 volts RMS in the input.... big preamplifiers..when i told them not to plug pre amplifiers unless if they can output 750 milivolts PEAK..also i asked them to listen with and without preamplifier...but happened that... amplifiers is not prepared to this..protection (diodes) in the input can control but produces some negative effect too..so..it is a solution and also a problem.
The amplifier was not made to receive square wave, several volts, high frequencies above the human audibility..and someone used a high output tone generator (function generator) into the amplifier...poor Q6 was BC546 and gone (brazilian green boards, standard Dx Blame ES/ST diagram)
The amplifier was not made to be connected to Bass guitar pre amplifier output, with all that gain and all that power demanding and all that high level of deep bass tones... and someone did that....he had overheat only.
So, almost 200 have made the amplifier.... 2 have Q6 burned....1 had overheat because bad use...these was the problems..so..the unit is safe and it is not an emergency to fix something DOES NOT NEED to be fixed as it is not wrong...the use is wrong..the abuse is what is wrong.
I suggest you , dear folks, not to worry too much...as i am in charge to worry about this stuff...i respect a lot the community, the amplifier brand, the Blameless basic design that inspired...i have strong respect and admiration by Doctor Self and i do not want to mess with that....i am checking and checking and checking and checking and checking..and doing that all time long..you can relax about that and change your focus to give a go into your amplifier to put it in large scale production and to offer to the community and mankind.... this is the worry, the concern and the kind of focus you should have...to be positive and productive and to do something usefull, not to repeat all the questions i do to myself about my amplifier daily..as i have deep concerns about..worries and i am always studing and thinking about..since i wake up till i go to the bed..and for sure there's a brain inside my skull too and i am able to think..maybe not too much intelligent..but wasting 10 times more time than you thinking i can realise things too....you are very clever Ostripper...also AndrewT is very skilled.
I would be more happy watching Andrew T using all his skills to produce something for us..to the communitty, in the place to be watching other guy's designs..this is not productive..in the place to have two awsome amplifier we gonna have only one.
Well.... i will not include the resistance officially...but forum members have skull and brain inside..no one is idiot or fool..all them skilled in their own way....all them can realise things and conclude things..if they want to take the risk to make modifications..they can do and enjoy his results.
I would like to inform in the future we gonna have Dx Blame MKIII (3) Supercharged... it will be produce in another international forum that is growing fast and i am there helping them too and have invited hundreds of brazilians to go there...to talk in english and also portuguese and to seel their stuff there as that forum is free to do that....and from that forum will be produced board to the MKIII, the one will receive boards and will be the center distributor man from the Dx Corporation is MEANMAN.... the one have always assembled Dx amplifiers, a friend and a cooperator that gonna distribute boards to whole world.... price is low...almost cost price with 10 percent to uncle charlie included.... first order will be 50 boards and i will have 2 boards for free to me...so...it will be alike group buy.... with very low profit..and you are invited to try the three output pairs Dx Blame amplifier (same..with three output pairs)...also we have Rudi/Omar (Metal) producing lovely boards you should order...as he is the only one is offering boards to the community for a while.
Be happy folks..enjoy life...produce designs, layouts, schematics, prototype and offer them to the community, produce boards and sell them to the communtity and stay always with us as you are, dear Ostripper, one of the good ones that produces things for all of us...very precious guy you are in my point of view..one of the diamonds we have in this forum.
MAKO, another forum exclusive design will arrive too, that will be offered cost price, in group buy too... will delay a couple of monthes...or a little bit more as i am producing torture on it for a while.
There's always video links in my signature... and they are changed daily, also video production use to be daily too.
regards,
Carlos
People can include the colector resistance if they want.... please inform the lowest possible value you have used and resulted fine... are you sure sounded the same?...say....have you tested this deeply?...listening for several hours with stop in between auditions? (ear adjust...ear plus brain adjusts).... have you tried several different musical programs....i have perceived differences in sonics... sounded less musical and more stérile with the resistance...but really protects a lot.
Be very carefull about what you say and suggest..so..check it three times..as people may try, may compare and if they perceive differences will not trust you anymore..then you can say thousands of truth and no one will give you attention.....we fight a lot, and for long time, to obtain their confidence....if we make ONE MISTAKE.....sadly they loose confidence in that easy way.... so...."this is better"...is something that should be said with a lot of care
To include the resistance people will have to cut colector lead to insert a series resistance or to produce a cut in the board copper track...and this is something terrible to a very developed board with a design that started by Todd Johnson...a hard work he has made..and several others developed the board too... Omar/Rudi.... also Mitchel, also Zharmo....well.... a lot of guys... seems Alexmm has made too....it is not a good idea to cut tracks and to insert parts this way.
I have decided to avoid the mess.... to increase associated resistances, the transistor power, also using heatsinks to drivers.
The main problem that you have not understood...or i have not used a good english to communicate with U2, Ostripper and AndrewT, is misuse..bad use.... torture.... the dangerous user.
I repeat...let's see if this time (third and last try) you capture what happened:
The amplifier was made and adjusted to produce full power with 750 milivolts PEAK into the input.... i had guys using 8 volts RMS in the input.... big preamplifiers..when i told them not to plug pre amplifiers unless if they can output 750 milivolts PEAK..also i asked them to listen with and without preamplifier...but happened that... amplifiers is not prepared to this..protection (diodes) in the input can control but produces some negative effect too..so..it is a solution and also a problem.
The amplifier was not made to receive square wave, several volts, high frequencies above the human audibility..and someone used a high output tone generator (function generator) into the amplifier...poor Q6 was BC546 and gone (brazilian green boards, standard Dx Blame ES/ST diagram)
The amplifier was not made to be connected to Bass guitar pre amplifier output, with all that gain and all that power demanding and all that high level of deep bass tones... and someone did that....he had overheat only.
So, almost 200 have made the amplifier.... 2 have Q6 burned....1 had overheat because bad use...these was the problems..so..the unit is safe and it is not an emergency to fix something DOES NOT NEED to be fixed as it is not wrong...the use is wrong..the abuse is what is wrong.
I suggest you , dear folks, not to worry too much...as i am in charge to worry about this stuff...i respect a lot the community, the amplifier brand, the Blameless basic design that inspired...i have strong respect and admiration by Doctor Self and i do not want to mess with that....i am checking and checking and checking and checking and checking..and doing that all time long..you can relax about that and change your focus to give a go into your amplifier to put it in large scale production and to offer to the community and mankind.... this is the worry, the concern and the kind of focus you should have...to be positive and productive and to do something usefull, not to repeat all the questions i do to myself about my amplifier daily..as i have deep concerns about..worries and i am always studing and thinking about..since i wake up till i go to the bed..and for sure there's a brain inside my skull too and i am able to think..maybe not too much intelligent..but wasting 10 times more time than you thinking i can realise things too....you are very clever Ostripper...also AndrewT is very skilled.
I would be more happy watching Andrew T using all his skills to produce something for us..to the communitty, in the place to be watching other guy's designs..this is not productive..in the place to have two awsome amplifier we gonna have only one.
Well.... i will not include the resistance officially...but forum members have skull and brain inside..no one is idiot or fool..all them skilled in their own way....all them can realise things and conclude things..if they want to take the risk to make modifications..they can do and enjoy his results.
I would like to inform in the future we gonna have Dx Blame MKIII (3) Supercharged... it will be produce in another international forum that is growing fast and i am there helping them too and have invited hundreds of brazilians to go there...to talk in english and also portuguese and to seel their stuff there as that forum is free to do that....and from that forum will be produced board to the MKIII, the one will receive boards and will be the center distributor man from the Dx Corporation is MEANMAN.... the one have always assembled Dx amplifiers, a friend and a cooperator that gonna distribute boards to whole world.... price is low...almost cost price with 10 percent to uncle charlie included.... first order will be 50 boards and i will have 2 boards for free to me...so...it will be alike group buy.... with very low profit..and you are invited to try the three output pairs Dx Blame amplifier (same..with three output pairs)...also we have Rudi/Omar (Metal) producing lovely boards you should order...as he is the only one is offering boards to the community for a while.
Be happy folks..enjoy life...produce designs, layouts, schematics, prototype and offer them to the community, produce boards and sell them to the communtity and stay always with us as you are, dear Ostripper, one of the good ones that produces things for all of us...very precious guy you are in my point of view..one of the diamonds we have in this forum.
MAKO, another forum exclusive design will arrive too, that will be offered cost price, in group buy too... will delay a couple of monthes...or a little bit more as i am producing torture on it for a while.
There's always video links in my signature... and they are changed daily, also video production use to be daily too.
regards,
Carlos
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Zharmo, i do love your boards and enthusiam too
So, we have respect and love to one each other.
thank you,
regards,
Carlos
So, we have respect and love to one each other.
thank you,
regards,
Carlos
I think you are being rather kind to the 2!
Maybe for them, you could re-name the amp "DX Flame" 😀
I don't think so Dave
More than 200 and only these guys faced troubles...all then non skilled in electronics..all them beginners...i do think it is a very good quantity of failures.
regards,
Carlos
More than 200 and only these guys faced troubles...all then non skilled in electronics..all them beginners...i do think it is a very good quantity of failures.
regards,
Carlos
funny
😛 Mr Carlos Sir, Myself and of course Evette just finished watching your all language video, and of course she can,t stop laughing
GREAT SHOW.
Regards Evette and Poppy
😛 Mr Carlos Sir, Myself and of course Evette just finished watching your all language video, and of course she can,t stop laughing
GREAT SHOW.Regards Evette and Poppy
Evette is a very sweet girl..... i am glad she has appreciated
her uncle charlie having fun.... you know...brazilians complains because only in english ..... i am in several international foruns and only in two brazilians ones..so...i use the language that can communicate more....english... despite my english is not good and that i have, still, to translate in my brain in advance to speak in english...it is not automatic, so...it is poor..as codes are not inside my brain.... i found this a way not to have to prepare two languages videos.... next will be absolutelly silent..video will talk in my place....here the stone age man video:
http://www.youtube.com/watch?v=NORmStFg5g4
About to increase condensers A Wayne...not needed..... some good guys told me that audio become blurred when we have too much condensers in the supply...i have tested and i could not perceive that...but.... you know... some guys are really good and they guarantee that is not a good idea to exagerate.
I suggest you to stick to the suggested values.... and do you know why?...because was tested...or you gonna have to test both options to realise the one you prefere...and i ensure you that comparisons are not something easy to be made...need a lot of skills...maybe you have them.... i do not know...i cannot read minds to evaluate other guy's minds.... well..i can read from some guys tuned..but this does not happens all time long.... i can listen Thomas C2sea...also i can listen Greg Erskine, despite i do not love some ideas inside his mind... about what he thinks about me (ahahahaha)...some of them i think i can....i have just to concentrate when they are waken up.
This may be a big "full ship"..... who knows?... i really cannot guarantee..i just go following the very good guys when i have doubts about.
regards,
Carlos
her uncle charlie having fun.... you know...brazilians complains because only in english ..... i am in several international foruns and only in two brazilians ones..so...i use the language that can communicate more....english... despite my english is not good and that i have, still, to translate in my brain in advance to speak in english...it is not automatic, so...it is poor..as codes are not inside my brain.... i found this a way not to have to prepare two languages videos.... next will be absolutelly silent..video will talk in my place....here the stone age man video:
http://www.youtube.com/watch?v=NORmStFg5g4
About to increase condensers A Wayne...not needed..... some good guys told me that audio become blurred when we have too much condensers in the supply...i have tested and i could not perceive that...but.... you know... some guys are really good and they guarantee that is not a good idea to exagerate.
I suggest you to stick to the suggested values.... and do you know why?...because was tested...or you gonna have to test both options to realise the one you prefere...and i ensure you that comparisons are not something easy to be made...need a lot of skills...maybe you have them.... i do not know...i cannot read minds to evaluate other guy's minds.... well..i can read from some guys tuned..but this does not happens all time long.... i can listen Thomas C2sea...also i can listen Greg Erskine, despite i do not love some ideas inside his mind... about what he thinks about me (ahahahaha)...some of them i think i can....i have just to concentrate when they are waken up.
This may be a big "full ship"..... who knows?... i really cannot guarantee..i just go following the very good guys when i have doubts about.
regards,
Carlos
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About power supply capacitors...
OEM's use less capacitance on purpose , barely adequate trafo as well. This is to have the power supply "sag" on purpose , allowing their barely adequate output stages to survive use by the consumer. To have "anal" amounts of supply reserve (capacitance) , any overcurrent event will have the power available to exceed SOA and blow the output stage. Study of OEM's has shown on average ,20kuF for 70w X 2 and 30Kuf for 100-120w X2 amps (Japanese). I am using 40Kuf @100V on my 120w/ch setup. If you have a over-engineered power supply (60kuf +) , you must match it with a the same output stage (example- 3 pair outputs for +/- 60V - 120w/ch amp) , especially if you are driving 4R loads.
PS - I only used 65,600uf total on 2- 250w/ch amps @ +/- 75V ... at full earthquake level .. less than 1v ripple was observed. plenty enough !!!
OS
OEM's use less capacitance on purpose , barely adequate trafo as well. This is to have the power supply "sag" on purpose , allowing their barely adequate output stages to survive use by the consumer. To have "anal" amounts of supply reserve (capacitance) , any overcurrent event will have the power available to exceed SOA and blow the output stage. Study of OEM's has shown on average ,20kuF for 70w X 2 and 30Kuf for 100-120w X2 amps (Japanese). I am using 40Kuf @100V on my 120w/ch setup. If you have a over-engineered power supply (60kuf +) , you must match it with a the same output stage (example- 3 pair outputs for +/- 60V - 120w/ch amp) , especially if you are driving 4R loads.
PS - I only used 65,600uf total on 2- 250w/ch amps @ +/- 75V ... at full earthquake level .. less than 1v ripple was observed. plenty enough !!!
OS
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5000uf to each ampere of consumption
Blame ST power consumption to full power (100W/4 ohms) is 2.5A each rail..so..use, to each channel (separated supply, one to each channel) 12.500uf to 15000 to each rail..total of 30 thousand uf to each channel.
If you decide to use only 8 ohms...then you can divide by two these values.
Picture shows dual Dx supplies using 15k plus 15K each one of them.
regards,
Carlos
Blame ST power consumption to full power (100W/4 ohms) is 2.5A each rail..so..use, to each channel (separated supply, one to each channel) 12.500uf to 15000 to each rail..total of 30 thousand uf to each channel.
If you decide to use only 8 ohms...then you can divide by two these values.
Picture shows dual Dx supplies using 15k plus 15K each one of them.
regards,
Carlos
Attachments
Last edited:
I don't understand how 100W rms/ 4 ohms can be developed with 2.5A.
What ripple level is achieved with "30 thousand uf to each channel" ?
Are the efforts by users to get 100W rms causing the parts to burn up ?
Thanks for your answers.
Noise is very little...if you inject subsonic tones, alike 8 hertz
Your speaker will move silently (we cannot listen this frequency) and you will not listen the mains noise even using 4 ohms speakers and full power...so.... it is good enougth this way.
1.5 amperes multiplied by 35 volts results in 87.5 watts of consumption to EACH rail..... so... total is 175 watts of consumption to produce 100 watts..you see that efficiency is within the class AB limits that sometimes reaches 65 percent.
To the speaker, you gonna have more current..combining both rail audio currents...audio may reach 5 amperes of audio and 20 volts RMS over 4 ohms speaker....or 2.5 amperes and 20 volts RMS over 8 ohms speakers.
I hope i could help you...needing anything more..please post your question.
regards,
Carlos
Your speaker will move silently (we cannot listen this frequency) and you will not listen the mains noise even using 4 ohms speakers and full power...so.... it is good enougth this way.
1.5 amperes multiplied by 35 volts results in 87.5 watts of consumption to EACH rail..... so... total is 175 watts of consumption to produce 100 watts..you see that efficiency is within the class AB limits that sometimes reaches 65 percent.
To the speaker, you gonna have more current..combining both rail audio currents...audio may reach 5 amperes of audio and 20 volts RMS over 4 ohms speaker....or 2.5 amperes and 20 volts RMS over 8 ohms speakers.
I hope i could help you...needing anything more..please post your question.
regards,
Carlos
Hi,
I posted results a few years ago that showed just how low that rail fuse can be.
I ended up recommending an F fuse rating of half the peak output current into the rated resistive load when operating at maximum power.
100W into 4r0 is equivalent to 28Vpk and 7Apk. Using my guidance this amplifier will run without blowing fuses if both supply rails are fitted with F3.5A fuses. Nearest next biggest size is F4A
Soon after I published this recommendation, Quasi quoted almost identical guidance.
Quasi said, choose a fuse with a rating that is half the rms output current when operating at full power into the rated load, i.e.F2.5A
F2.5A should never blow when reproducing any music signal from +-35Vdc to 4ohm speaker.
Search my Krell Klone posts and Leach clone posts for fuse and power details.
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