Hi JC
The tower speakers are diy. Seas brand drivers, 10" bass driver with ported enclosure good till 30hz. Mid driver is a 5" and tweeter is a fabric dome tweeter. If you need more info please pm me as it will be off topic on this forum.
Regards
Niss_man
If you push your Dx Blame ES or Dx Blame ST above it's limits
entering clipping..then you may experience Q6 burning... then substitute it by 2N5551 because this one is stronger...accept more voltage from colector to emitter and more current than the BC546.
Happened in Brasil, some guys here drive the amplifier very hard... two had BC546 burned.... one use generic counterfeit BC546.... the other used square wave generator, high frequency and high level.
We had one friend from Germany that had troubles too.
Another way is to increase emitter resistance value..from 220 ohms to 1K...but really sonics changes a lot..better to replace it by a stronger transistor and be more kind with the volume knob.
Supercharged blue boards already use 2N5551 to Q6 position...so.... this one is already replaced...but also you can use stronger transistor there if you want....just avoid to replace the 220 ohms resistance.
1K there is an excelent electrical and technicall advice (Doctor Self uses this value there)...but sonically i have found 220 ohms better...also simulating was better.
regards,
Carlos
entering clipping..then you may experience Q6 burning... then substitute it by 2N5551 because this one is stronger...accept more voltage from colector to emitter and more current than the BC546.
Happened in Brasil, some guys here drive the amplifier very hard... two had BC546 burned.... one use generic counterfeit BC546.... the other used square wave generator, high frequency and high level.
We had one friend from Germany that had troubles too.
Another way is to increase emitter resistance value..from 220 ohms to 1K...but really sonics changes a lot..better to replace it by a stronger transistor and be more kind with the volume knob.
Supercharged blue boards already use 2N5551 to Q6 position...so.... this one is already replaced...but also you can use stronger transistor there if you want....just avoid to replace the 220 ohms resistance.
1K there is an excelent electrical and technicall advice (Doctor Self uses this value there)...but sonically i have found 220 ohms better...also simulating was better.
regards,
Carlos
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A friend used the Dx Blame ST to play distorted guitar ... saturating the input
with high frequencies and square waves... sustain audio and some feedback.
Good test.
YouTube - Dx Blame ES o Amplificador de Ferro
regards,
Carlos
with high frequencies and square waves... sustain audio and some feedback.
Good test.
YouTube - Dx Blame ES o Amplificador de Ferro
regards,
Carlos
I will share the ultimate solution to the Q6 issue. I have implemented it , and tested it with full clip and dead short on my small output stage. (below)
with a 2R load , it will soft clip. VAS is limited to 14mA ... period. Only drawback ... one more device.
This does not affect sound at normal or even very high levels. Just with OP shorts and gross overdrive of input stage. Mine does 130V p-p @ 11ma VAS.
OS
Attachments
I see.... i have use this method in earlier amplifiers...the Precision has this
circuit....but know i cannot use anymore dear Ostry..there are hundreds of boards provided spread wide world.... the solution must be offered without modifications in the board...there's no room to protection in that board.
Interesting thing...i have several amplifiers playing here....not only or two..i have 8 stereos...and i had no troubles...but happened not more than once...but twice and three times...so...for sure this needs some care.
I cannot ask people to solder parts below boards dear Ostry...they bougth boards in group buy...cheap boards for sure..but offered to do the job without parts soldered bellow them.
A friend that loves deeply this amplifiers (he is rigth about love of Blameless designs...they are just the best possible option!...of course including yours that are Blameless style too)... he used his guitar..full power into the Dx Blame ST.... he included distortion and feedback..square wave full of crazy harmonics.....heavy metal sound.... this is all we need to torture amplifiers...and nothing happened.... he use to say that i have not the obligation to produce amplifiers to face Caterpillar heavy machines going over the board.
hehehehehhe...he is funny....and fanatic by Blames too... watch here...or listen here because he is shy and light is off...only sound:
YouTube - Dx Blame ES o Amplificador de Ferro
Solution changing circuit is not a solution....is a problem dear Ostry...is create another amplifier..and my Dx Blame models are definitive.... the last and best wide world possible sonics...the greatest design from Doctor Self that i had the good idea to tweak to my style.
The best is the best....others are others.
regards,
Carlos
circuit....but know i cannot use anymore dear Ostry..there are hundreds of boards provided spread wide world.... the solution must be offered without modifications in the board...there's no room to protection in that board.
Interesting thing...i have several amplifiers playing here....not only or two..i have 8 stereos...and i had no troubles...but happened not more than once...but twice and three times...so...for sure this needs some care.
I cannot ask people to solder parts below boards dear Ostry...they bougth boards in group buy...cheap boards for sure..but offered to do the job without parts soldered bellow them.
A friend that loves deeply this amplifiers (he is rigth about love of Blameless designs...they are just the best possible option!...of course including yours that are Blameless style too)... he used his guitar..full power into the Dx Blame ST.... he included distortion and feedback..square wave full of crazy harmonics.....heavy metal sound.... this is all we need to torture amplifiers...and nothing happened.... he use to say that i have not the obligation to produce amplifiers to face Caterpillar heavy machines going over the board.
hehehehehhe...he is funny....and fanatic by Blames too... watch here...or listen here because he is shy and light is off...only sound:
YouTube - Dx Blame ES o Amplificador de Ferro
Solution changing circuit is not a solution....is a problem dear Ostry...is create another amplifier..and my Dx Blame models are definitive.... the last and best wide world possible sonics...the greatest design from Doctor Self that i had the good idea to tweak to my style.
The best is the best....others are others.
regards,
Carlos
Less invisible image
YouTube - Less invisible Renatovisky Metal man
in the floor you can see the Dx Blame supply red light.... sound is generated in the guitar amplifier and sent to the Blame in the pre amplifier level...the Blames is producing the amplifications and sound is sent back to the guitar amplifier case, in this time it is used only the speaker as output device.
He said never listened so nice sound to guitar or music.
regards,
Carlos
YouTube - Less invisible Renatovisky Metal man
in the floor you can see the Dx Blame supply red light.... sound is generated in the guitar amplifier and sent to the Blame in the pre amplifier level...the Blames is producing the amplifications and sound is sent back to the guitar amplifier case, in this time it is used only the speaker as output device.
He said never listened so nice sound to guitar or music.
regards,
Carlos
You can replace Q6 by 2N5551, because some guys reported failures in Q6
We had three guys that informed had Q6 burned..it is a 100 miliamperes transistor, really not too much strong...... 2N5551 can hold more current, more voltage.....or more power if you want.
But you should twist your transistor 180 degrees, because 2N5551, the new transistor for Q6 position had different pin layout.
Supercharged and blue boards does not need that, as this new board was made to 2N5551 and 1N5401 transistors to all models.
But Brazilian blue boards and the original Todd Johnson layout will need to twist the transistor....watch the picture and you see that it is assembled 180 degrees twisted.
regards,
Carlos
We had three guys that informed had Q6 burned..it is a 100 miliamperes transistor, really not too much strong...... 2N5551 can hold more current, more voltage.....or more power if you want.
But you should twist your transistor 180 degrees, because 2N5551, the new transistor for Q6 position had different pin layout.
Supercharged and blue boards does not need that, as this new board was made to 2N5551 and 1N5401 transistors to all models.
But Brazilian blue boards and the original Todd Johnson layout will need to twist the transistor....watch the picture and you see that it is assembled 180 degrees twisted.
regards,
Carlos
Attachments
I will share the ultimate solution to the Q6 issue. I have implemented it , and tested it with full clip and dead short on my small output stage. (below)
with a 2R load , it will soft clip. VAS is limited to 14mA ... period. Only drawback ... one more device.
This does not affect sound at normal or even very high levels. Just with OP shorts and gross overdrive of input stage. Mine does 130V p-p @ 11ma VAS.
OS
A common solution as given by Stochini (EE May 1983) and later Doug Self but an improvement, mentioned by others (inc Andrew T), is to split the VAS degen to ensure premature operation of the protection device doesn't arise at any turn-on voltage.
I modified my "DX-Precision" as shown.
Brian.
I bet many people have said this. Including myself.
Carlos, what are your plans for your next amplifier design?Regards
Niss_man
No, i have no plans about.... it seems to me i cannot make better than the best to my
ears... so long time searching and listening and testing and assembling amplifiers...i found the one!.....i doubt i can make better.
I am playing with speakers crossovers and confirming my thougths:
- A hell to the flat... sound must be good to my ears, beeing flat or not flat (instruments problems not mine)...must take in account my my home acoustics, my home ressonances and my musical taste.... must use an amplifier without tone controls and not feel bothered with sonics.
I have discovered interesting things about speaker crossovers...and will produce a video and you will have the link Simon..also other close friends.... some tricks about where to pick the treble in the passive crossover, how to produce loudness contour to listen low power, the mid range issues and special inductors to the woofer....how to perceive extremelly ballanced sonics and to perceive when each driver are playing in separate..without mess the whole thing with a single source of music from "the box".... now i can perceive each driver when entering in action....you know...finishing with the hell "milk shake".... when you cannot feel the milk, the suggar and the chocolate..the idea is to perceive each one of them in separate without be mixed in a mess of things with a resultant taste that is not milk, not chocolate and not suggar... to listen three women singing and to be able to perceive each one of them clearly..without that harmonic resultant...when seems a single voice with electronic stuff repeating the same voice three times with some delay.
- Also playing with meters, or ligth indications....i want transistorized, discrete, and if you have three leds..measuring 10 watts, 40 watts and 160 watts.... then i want the 10 watts one to go off (led off, dark, no ligth) when reaching 40 watts.... i am working on that and feeling i got some tricks about....of course i do not want chips..it is the maximum possible of lack of creativity and imagination to assemble already made things inside a chip...aaagh!... to build using chips it is better to buy already made things.
- Also trying tone controls to my daugthers, as they need that and asked me that...i do not like them..noisy, distorters..awfull things...but working to obtain the best possible solution...i think i found one...working on it.
No more hard work to uncle charlie...others should offer amplifiers...this takes too much time, planing, research, building, tests, some torture and need our continuous follow up.... some guys bothers a lot when see others working and there are much more suggestions than people moving their hands to do real things...i do think i made my part of this stuff to the communitty, it is time to others to work hard.....now i am listening, having pleasure....working only to give some follow up and help to the last group buy builders..the blue board builders.... so, my activities will reduce till almost stop...i am going to the audience...not more on the stage.
regards,
Carlos
ears... so long time searching and listening and testing and assembling amplifiers...i found the one!.....i doubt i can make better.
I am playing with speakers crossovers and confirming my thougths:
- A hell to the flat... sound must be good to my ears, beeing flat or not flat (instruments problems not mine)...must take in account my my home acoustics, my home ressonances and my musical taste.... must use an amplifier without tone controls and not feel bothered with sonics.
I have discovered interesting things about speaker crossovers...and will produce a video and you will have the link Simon..also other close friends.... some tricks about where to pick the treble in the passive crossover, how to produce loudness contour to listen low power, the mid range issues and special inductors to the woofer....how to perceive extremelly ballanced sonics and to perceive when each driver are playing in separate..without mess the whole thing with a single source of music from "the box".... now i can perceive each driver when entering in action....you know...finishing with the hell "milk shake".... when you cannot feel the milk, the suggar and the chocolate..the idea is to perceive each one of them in separate without be mixed in a mess of things with a resultant taste that is not milk, not chocolate and not suggar... to listen three women singing and to be able to perceive each one of them clearly..without that harmonic resultant...when seems a single voice with electronic stuff repeating the same voice three times with some delay.
- Also playing with meters, or ligth indications....i want transistorized, discrete, and if you have three leds..measuring 10 watts, 40 watts and 160 watts.... then i want the 10 watts one to go off (led off, dark, no ligth) when reaching 40 watts.... i am working on that and feeling i got some tricks about....of course i do not want chips..it is the maximum possible of lack of creativity and imagination to assemble already made things inside a chip...aaagh!... to build using chips it is better to buy already made things.
- Also trying tone controls to my daugthers, as they need that and asked me that...i do not like them..noisy, distorters..awfull things...but working to obtain the best possible solution...i think i found one...working on it.
No more hard work to uncle charlie...others should offer amplifiers...this takes too much time, planing, research, building, tests, some torture and need our continuous follow up.... some guys bothers a lot when see others working and there are much more suggestions than people moving their hands to do real things...i do think i made my part of this stuff to the communitty, it is time to others to work hard.....now i am listening, having pleasure....working only to give some follow up and help to the last group buy builders..the blue board builders.... so, my activities will reduce till almost stop...i am going to the audience...not more on the stage.
regards,
Carlos
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Yes , the leach amp does it this way. Referencing a 47R VAS degeneration resistor gives 12.5mA - 33R=21mA - 22R=27mA (Cordell's example). With my low current 6.1mA setup , the 12.5 is quite enough.
Like Carlos , I never had any issues with the beta device (Q6) besides a little warmth. I added the extra device just to make "damn" sure.
OS
I have asked Renatovsky Kalishinikova to torture the Dx Blame ST
Using a BC546 as original in the first VAS stage...and survived.
I have asked him to saturate the input with three times the level needed to drive the power amplifier to it's maximum power...to use 4 ohms and standard power supply...so...overdrive was used and survived!
So, if you keep it will work fine this way..if you want even more safety, then replace Q6 by a 2N5551 or even a BD139.
YouTube - Dx Blame ES "O Amplificador de Ferro ll"
I am uploading video about the " L " adaptor Issue.... this adaptor made in Brazil is NO GOOD!
regards,
Carlos
Using a BC546 as original in the first VAS stage...and survived.
I have asked him to saturate the input with three times the level needed to drive the power amplifier to it's maximum power...to use 4 ohms and standard power supply...so...overdrive was used and survived!
So, if you keep it will work fine this way..if you want even more safety, then replace Q6 by a 2N5551 or even a BD139.
YouTube - Dx Blame ES "O Amplificador de Ferro ll"
I am uploading video about the " L " adaptor Issue.... this adaptor made in Brazil is NO GOOD!
regards,
Carlos
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The " L " adaptor issue to the Dx Blame amplifiers
These " L" adaptors are not used only by Brazilians, but it is suggested to everyone to use this style (when have not the natural flange in their heatsink):
YouTube - The adaptor issue 1
YouTube - The adaptor issue 2
regards,
Carlos
These " L" adaptors are not used only by Brazilians, but it is suggested to everyone to use this style (when have not the natural flange in their heatsink):
YouTube - The adaptor issue 1
YouTube - The adaptor issue 2
regards,
Carlos
hello...everybody....i im currently making an order from mouser...and need Your help:
they don't have Nichicon KZ in Stock following values: 2pcs 4700uF/50V and 2pcs 10000uF/50V...so could i use Nichicon KZ 4pcs 8200uF/50V ?
for use on DX Blame ST board i will use Vishay/Dale RN60D 1/4W and RN65D 0,5W resistors...for DX PSU boards they dont have RN60D in high wattage...so could i use following models:
R1, R2 5K6 +/-5% 2W Vishay/Dale (CPF25K6000JKB14)
R3, R4 0R47 +/-5% 3W Vishay/Dale (CPF3R47000JNB14) 3W instead of 2W for CR filtering
R5, R6 3R3 +/-5% 3W Vishay/BC Components (PR03000203308JAC00)
R7, R8 2K2 +/-1% 2W Vishay/Dale (CPF22K2000FKE14)
It's hard to find 1n5/63V to 100V MKP(becuse of big dimensions) so i use EPCOS 1n5/100V MKT... i think that not using MKP in DX PSU board dont have any difference in sound quality?
Many thanks
they don't have Nichicon KZ in Stock following values: 2pcs 4700uF/50V and 2pcs 10000uF/50V...so could i use Nichicon KZ 4pcs 8200uF/50V ?
for use on DX Blame ST board i will use Vishay/Dale RN60D 1/4W and RN65D 0,5W resistors...for DX PSU boards they dont have RN60D in high wattage...so could i use following models:
R1, R2 5K6 +/-5% 2W Vishay/Dale (CPF25K6000JKB14)
R3, R4 0R47 +/-5% 3W Vishay/Dale (CPF3R47000JNB14) 3W instead of 2W for CR filtering
R5, R6 3R3 +/-5% 3W Vishay/BC Components (PR03000203308JAC00)
R7, R8 2K2 +/-1% 2W Vishay/Dale (CPF22K2000FKE14)
It's hard to find 1n5/63V to 100V MKP(becuse of big dimensions) so i use EPCOS 1n5/100V MKT... i think that not using MKP in DX PSU board dont have any difference in sound quality?
Many thanks
Hi Carlos!
I'm planning to build Blame Es and I have several questions:
Will be a problem to increase the input sensitivity by increase the value of R13 from 12 to 15K Ohms. Will this affect the stability of the amp?
I will use the amp with +/- 33V DC. Do I need to change some of the values of the resistors in the schematic?
Thanks.
I'm planning to build Blame Es and I have several questions:
Will be a problem to increase the input sensitivity by increase the value of R13 from 12 to 15K Ohms. Will this affect the stability of the amp?
I will use the amp with +/- 33V DC. Do I need to change some of the values of the resistors in the schematic?
Thanks.
No dear Astankov, you can tweak R13 and R2..but make them almost the same value
These resistances, in special R2, in the input, from base to ground, is the one you can understand as the input impedance...say..input impedance is not too much different than it's value.... R2 beeing 47K, then input impedance is almost 47K..... R2 beeing 10K, then input impedance is almost 10K.
I have perceived that 10K works better...also i could notice that 12K (R13 having 20 percent bigger resistance compared to R2.... resulted better in sonics and worse in off set).
The gain ratio depends on R13 divided by R2.....but...... we have gain one, or almost one in this case... BUT.... we have something that change that...the resistance to ground (in series with an electrolitic condenser) that controls the gain...so, now you divide R2 by that resistance..... and the one is R7.
R7 adjusts sensitivity..it is 820 ohms to 1 Volt peak input (700 mv rms aprox.)...and this way you will have full power in the output....but you can REDUCE it to increase the sensitivity.... i have used 390 ohms to plug this same amplifier into a satelite receiver (International Broadcasting reception)...so.... increase your sensitivity reducing R7 instead to tweak R13 and R2....but off course this unballances gain too and produces increases in gain too...but it is easier, and less harmfull if you tweak R7.
No, no need to change resistances because of less voltage in your supply....this amplifier operates without any modification (tested) from 12 plus 12 volts till 44 plus 44 volts....anything to change on it.
regards,
Carlos
These resistances, in special R2, in the input, from base to ground, is the one you can understand as the input impedance...say..input impedance is not too much different than it's value.... R2 beeing 47K, then input impedance is almost 47K..... R2 beeing 10K, then input impedance is almost 10K.
I have perceived that 10K works better...also i could notice that 12K (R13 having 20 percent bigger resistance compared to R2.... resulted better in sonics and worse in off set).
The gain ratio depends on R13 divided by R2.....but...... we have gain one, or almost one in this case... BUT.... we have something that change that...the resistance to ground (in series with an electrolitic condenser) that controls the gain...so, now you divide R2 by that resistance..... and the one is R7.
R7 adjusts sensitivity..it is 820 ohms to 1 Volt peak input (700 mv rms aprox.)...and this way you will have full power in the output....but you can REDUCE it to increase the sensitivity.... i have used 390 ohms to plug this same amplifier into a satelite receiver (International Broadcasting reception)...so.... increase your sensitivity reducing R7 instead to tweak R13 and R2....but off course this unballances gain too and produces increases in gain too...but it is easier, and less harmfull if you tweak R7.
No, no need to change resistances because of less voltage in your supply....this amplifier operates without any modification (tested) from 12 plus 12 volts till 44 plus 44 volts....anything to change on it.
regards,
Carlos
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