Replacement suggestions.
This BC840 is the one reduces a lot distortion..but you can try a bigger one, alike MJE340/350....also i think 2N5401/5551 may work too.
To the drivers and CCS, you can use other transistors able to dissipate 10 watts and units that can face 200 volts or more from colector to emitter..there are millions of units you can use....current will not be the problem...and even the smaller one in To220 case will be able to face that current or more.
To the drivers you can even use the same transistors you use in the ouput..they can work fine there too, despite some small loss in gain...also i have used the power transistor as CCS to drivers.
BC546/556 can be substituted by 2N5401/5551 and other million of models, ancient and new models.
The output transistor may be units that can operate with more than 200 volts from colector to emitter, units able to face 5 amperes or more from colector to emitter, units to dissipate 100 watts or more.... so, these one you mentioned will fit...and other millions of transistors will fit too.
I am not the best one to suggest options of transistors, but at least i have tried to help...let's listen others....wait a little bit to see if other suggestions will be posted...as these guys are crazy to help..you see how they have jumped in the thread?... crazy to help maybe...we gonna see that soon.
Discussions man...people do not read the thread and come to discuss....i was already very damned with my amplifier and was screaming with the amplifier..saying why he have not burned when Mr. Soa arrived.
ahahahahahah!
Here we do not earn money..but at least we have lots of fun!
Dear Eesbiboi, i have a lot to do, and i cannot stay here for too long..will let you with these folks that for sure will work hard to help you.
Carlos
daghan salamat sir carlos,
so this means...
BC840 = MJE340/350 = 2N5401/5551
BC546/556 = 2N5401/5551
output tranny = 2sc5200/a1943
drivers = output trannies...
id rather say CONSULTANTS/ADVICERS...
TOTALLY wrong advice , those devices are as different as cars and trucks , night and day.
MR. SOA = "This is only a starting point, because we must have a safety margin. Remember that the peak dissipation into a reactive load with a 45° phase angle is almost double that calculated above, about 1900W. If the transistors can be maintained at 25°C (not likely), that's fine, but we need to add more to allow for elevated temperature. I have elected to use 9 output devices, with a tenth device used as a driver. This maintains worst case peak dissipation at 212W - not much of a safety margin, but it should be ok in practice - in part because the supply voltage will collapse under load. "
quote from Rob elliot - ESP audio
This is not a toy amp , like DX original this is a BOMB!!
OS
Having built and tested a design more than 20 years ago that had plus and minus 120 volt rails, I am finding it hard to understand what the danger is here.
Is it the DESIGN or the voltages being worked with?
I used TWO Dunlap Clarke transformers to develop the voltages above.
I used 6 GE caps, three for each rail that where rated at 150 volts and either 20,000 or 40,000 uf each, (sorry my memory is not what it used to be).
This was for a SINGLE channel of a 746 watts @ 8 ohms design using mj15003 and mj15004 ( do not trust my memory on this) but I used 9 driven by 1 on each rail of these devices.
I knew the dangers, but practiced safety and used a 25 amp variac.
IT worked then and I am going there again soon, I hope.
Dangerous? YES, doable YES, but so is driving down the street and going to a airport to climb on a plane to fly across an Ocean at night with one engine. THINK Lindbergh...
I encourage ALL to LIVE LIFE and BE CAREFUL....enjoy the results...
Is it the DESIGN or the voltages being worked with?
I used TWO Dunlap Clarke transformers to develop the voltages above.
I used 6 GE caps, three for each rail that where rated at 150 volts and either 20,000 or 40,000 uf each, (sorry my memory is not what it used to be).
This was for a SINGLE channel of a 746 watts @ 8 ohms design using mj15003 and mj15004 ( do not trust my memory on this) but I used 9 driven by 1 on each rail of these devices.
I knew the dangers, but practiced safety and used a 25 amp variac.
IT worked then and I am going there again soon, I hope.
Dangerous? YES, doable YES, but so is driving down the street and going to a airport to climb on a plane to fly across an Ocean at night with one engine. THINK Lindbergh...
I encourage ALL to LIVE LIFE and BE CAREFUL....enjoy the results...
Funny how we agree on number of devices, I wrote my post while you were posting yours and did not see your post first... Thanks
Both ... this is a butchered linn topology amp using drivers in the voltage amp to avoid using a proper triple output stage. VERY crude.
It should have a low current precision VAS (6-8 Ma) with at least a capacitance multiplier for and a proven current stage (triple with MJL21193/4's or TO-3 devices)
The voltages are VERY lethal , I am more experienced than some but even I treat voltages as low as 77-0-77VDC (my amp) as I would a BOMB.
My issue is that a hobbyist's who do not know how to determine the suitability of transistor substitutes should not listen to someone who tells them all transistors are the same.
Also , I would not suggest they even attempt to build a 1KW amplifier.OS
Those are REAL output devices ... lower Ft as well (less prone to oscillation), the only plastic device I would even consider is the MJL21193/4 with over 2A Mr. SOA per device.
OS
the proposal shown at the beginning of this thread is not a design.
It is little more than a cobbled together collection of circuits with almost random selection of components and values. Many of it's values are simply wrong, many of the devices are simply wrong.
The assembler of this proposal does not recognise how little they know and from such a lack of knowledge cannot even respond to suggestions for corrections/substitutions/replacements or simply to give up and accept the proposal cannot and should not be in the Forum.
It is irresponsible to promote this as a designed amplifier.
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Some will believe that all transistors are the same (example ; mje340/350 , Bc546) , I do not. The fact that they do trust that statement is scary indeed , as well as not knowing how to assess a suitable substitute using datasheets. Should you be advising them to build deadly amplifiers ??
You could of just copy/ pasted the SOA curve of the device instead of posting the whole datasheet. (below) you would need 15 pair of your OP's !!!
I built the DX amp and appreciate your contribution to the community.
It is a toy because it HAS to work , and it works with just about any device.
The DX amp , blame ES , and your true Blameless amp are very good , I have built them with my parts and small changes. Sound designs that have been
with us a long time.
Alex MM makes a good board , but the one I saw will not work for 16 amps. You need a much larger board with copper wire soldered along the power rails and a HUGE heatsink with forced air cooling. Aussieamps did this (picture 3) , he runs a REAL business selling amps that are of very sound engineering.
This amp is different , it needs to be PERFECT. You can not use output relays with it , as it can be a good arc welder .. too . At least do a loop gain simulation of it to ABSOLUTELY ensure it's stability. Don't be scared of triples , with MJE340/350 - output - output (mjl21193/4) , this triple has very low current gain compared to most triples with no stability problems. The mje15032/33 won't be reliable .. neither will just a simple EF2 be effective for a good amp of this calibre.
OS
POST CORRECTED.
Absolutely , THE AMP is substandard.. not the creator . It will not be safe , to build it is not safe. If I submitted a 1000w amp , I would be open to any criticism as to it's safety and make the changes.
Especially if the prospective builders were not well versed in an amp at this power level I would not report the post as offensive. I was only critical of the design and the mans refusal to accept ANY criticism about it.
If I was to moderate , I would instead advise on the importance of safety and a good design for this lethal WMD. Rod Elliot's #117 is a perfect example.
I did leave my positive comments in the corrected post for all to see and did not mention the very negative PM I received in response to a truthful assessment of a bad design.
OS
You could of just copy/ pasted the SOA curve of the device instead of posting the whole datasheet. (below) you would need 15 pair of your OP's !!!
I built the DX amp and appreciate your contribution to the community.
It is a toy because it HAS to work , and it works with just about any device.
The DX amp , blame ES , and your true Blameless amp are very good , I have built them with my parts and small changes. Sound designs that have been
with us a long time.
Alex MM makes a good board , but the one I saw will not work for 16 amps. You need a much larger board with copper wire soldered along the power rails and a HUGE heatsink with forced air cooling. Aussieamps did this (picture 3) , he runs a REAL business selling amps that are of very sound engineering.
This amp is different , it needs to be PERFECT. You can not use output relays with it , as it can be a good arc welder .. too . At least do a loop gain simulation of it to ABSOLUTELY ensure it's stability. Don't be scared of triples , with MJE340/350 - output - output (mjl21193/4) , this triple has very low current gain compared to most triples with no stability problems. The mje15032/33 won't be reliable .. neither will just a simple EF2 be effective for a good amp of this calibre.
OS
I'll make it official:
Play the ball, not the man.
/Hugo
ostripper: please save your post and repost without the personal stuff. Your current post will be gone in five minutes.
POST CORRECTED.
Absolutely , THE AMP is substandard.. not the creator . It will not be safe , to build it is not safe. If I submitted a 1000w amp , I would be open to any criticism as to it's safety and make the changes.
Especially if the prospective builders were not well versed in an amp at this power level I would not report the post as offensive. I was only critical of the design and the mans refusal to accept ANY criticism about it.
If I was to moderate , I would instead advise on the importance of safety and a good design for this lethal WMD. Rod Elliot's #117 is a perfect example.
I did leave my positive comments in the corrected post for all to see and did not mention the very negative PM I received in response to a truthful assessment of a bad design.
OS
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Dear Eesbiboi, ask these ones that criticise my design, the transistors they
would use if they would build the unit... and you should use their instructions as you matter for me....builder's matters.
I am sorry not to make it myself.... i am sure some folks are not real friends....and i dislike to be behaving fake being kind with them.
If tjese substitution i have pointed are under suspection, and i cannot test what i have suggested, as i have no more these units to use...i think it will be more safe to you, to use the original parts, because i have tested them and i can guarantee what i have found in real life...if not...if you cannot find the original ones, then try the ones suggested by the critics.
They are ringing the alarm because they want...as i told everybody, i have a working unit and had not problems... real life test has much more value in my point of view.
If something strange happens after you accept elsewhere suggestions, despite i believe anything wrong may happens, you know what are the untested parts and to wich one complain.
I have doubt about the BC840 substitution only, and i have not units to try... i have soldered and tried the MJE15032 in it's place and worked fine...but you said cannot find these transistors in your place.
MJE15034 and MJE15035 may work fine too..but same problem to find in your place if i understood correctly.
regards,
Carlos
would use if they would build the unit... and you should use their instructions as you matter for me....builder's matters.
I am sorry not to make it myself.... i am sure some folks are not real friends....and i dislike to be behaving fake being kind with them.
If tjese substitution i have pointed are under suspection, and i cannot test what i have suggested, as i have no more these units to use...i think it will be more safe to you, to use the original parts, because i have tested them and i can guarantee what i have found in real life...if not...if you cannot find the original ones, then try the ones suggested by the critics.
They are ringing the alarm because they want...as i told everybody, i have a working unit and had not problems... real life test has much more value in my point of view.
If something strange happens after you accept elsewhere suggestions, despite i believe anything wrong may happens, you know what are the untested parts and to wich one complain.
I have doubt about the BC840 substitution only, and i have not units to try... i have soldered and tried the MJE15032 in it's place and worked fine...but you said cannot find these transistors in your place.
MJE15034 and MJE15035 may work fine too..but same problem to find in your place if i understood correctly.
regards,
Carlos
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Carlos,
On a lighter note. A few posts back you said you were dancing with a beautiful blonde. With all of the gorgeous dark haired, brown eyed Brazilian beauties where did you find a blonde? She probably likes to solder too.
Even though this is DIY for fanatics I like your build it and use it logic. Sometimes the numbers just do not work as good as the real thing. The engineering literature is full of information we can use and most of it is geared to the conservative side. I have found that much of what I build is much more tolerant of my inexperience and just seems to survive. I hope you continue to give us as many toys to try out as you can come up with. Just how many 1000 watt amps have been displayed here at this forum. My count is not too many. We are always seeing 60 to 100 watt amps geared to very efficient speakers. I do not have any efficient speakers and need every watt I can build in.
How about something like 2500 watts. I have an old welder that needs a home. That is what an outdoor concert starts with here in Georgia. It is not uncommon to find 200000 watts on the stage.
There is a song somewhere with this in the lyrics. "Do not even think of going to Georgia with less than 200000 watts."
Tad
On a lighter note. A few posts back you said you were dancing with a beautiful blonde. With all of the gorgeous dark haired, brown eyed Brazilian beauties where did you find a blonde? She probably likes to solder too.
Even though this is DIY for fanatics I like your build it and use it logic. Sometimes the numbers just do not work as good as the real thing. The engineering literature is full of information we can use and most of it is geared to the conservative side. I have found that much of what I build is much more tolerant of my inexperience and just seems to survive. I hope you continue to give us as many toys to try out as you can come up with. Just how many 1000 watt amps have been displayed here at this forum. My count is not too many. We are always seeing 60 to 100 watt amps geared to very efficient speakers. I do not have any efficient speakers and need every watt I can build in.
How about something like 2500 watts. I have an old welder that needs a home. That is what an outdoor concert starts with here in Georgia. It is not uncommon to find 200000 watts on the stage.
There is a song somewhere with this in the lyrics. "Do not even think of going to Georgia with less than 200000 watts."
Tad
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Good conversation Tryonziess... i felt good perceiving you friendly this way
It is good to know we have good friends too.
The blond is rarity here..... and we all love rarities.....in Sweden they love dark brown eyes... everybody there has green or blue eyes..... blondes usually likes dark guys.... Germans comes to my place and return with a local women to make a nice marriage...and very few return to our country.... that blond had class, swing in the movements, soft movement.... alike floating...i felt her extremelly interesting....because the way she moves.
Well.... super power amplifiers...only for powerholics...i did that one because of Sakis.... i really never had such interest...but i see that here, people appreciate power..it is popular here and there are more guys building the power units i have made than 50 watter units.
A big hug to you... will let you dance with that blonde too Tryon..... i will be watching...maybe will be better to watch than to dance.... she floats!
regards,
Carlos
It is good to know we have good friends too.
The blond is rarity here..... and we all love rarities.....in Sweden they love dark brown eyes... everybody there has green or blue eyes..... blondes usually likes dark guys.... Germans comes to my place and return with a local women to make a nice marriage...and very few return to our country.... that blond had class, swing in the movements, soft movement.... alike floating...i felt her extremelly interesting....because the way she moves.
Well.... super power amplifiers...only for powerholics...i did that one because of Sakis.... i really never had such interest...but i see that here, people appreciate power..it is popular here and there are more guys building the power units i have made than 50 watter units.
A big hug to you... will let you dance with that blonde too Tryon..... i will be watching...maybe will be better to watch than to dance.... she floats!
regards,
Carlos
sir,...
in my previous amp build, i have replaced mje15032 with c4793... will this tranny be suitable enough to do the job for BC 818-40 ???...
as for here in our place mje's are really very hard to find...
salamat,
ees...
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I fail to grasp the need or fascination with huge power amps like this.
That being said, It is a very good design amp that will work for years at a much more reasonable supply voltage of +- 65 volts
4 output pairs is plenty for 8 ohms. this gives an easy 200w RMS which would require 2Kw to double the sound volume.
if more power is required for subs, use multiple drivers
That being said, It is a very good design amp that will work for years at a much more reasonable supply voltage of +- 65 volts
4 output pairs is plenty for 8 ohms. this gives an easy 200w RMS which would require 2Kw to double the sound volume.
if more power is required for subs, use multiple drivers
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