I am starting to make a new Dx amplifier.... and i have posted something at the Dx amplifier thread...but i have changed my mind to feed the old thread and now i am opening a new one.
It is a Dx amplifier for high power (not exactly the same DHR Turbo)...and for bass.
It will be able to work with 2 ohms loads and it is possible to reach 1.3 Kilowatts of RMS output power (0.6% distortion) from 35 to 200 hertz.
I will start trying passive input filter.... no VBE multiplier gonna be used, i gonna use 4 high speed diodes in series and a string of resistors and trimpots.
An extra board will be made to produce two boards, this will help to avoid piracy because will turn pirate's life hard..they will be forced to make two pcboards and interconnect them.... or to produce and sell two boards...expensive thing because too many transistors in the output (maximum of 20 units)
Renato Comerlatte and Juan Vargas (Vargas Mongo) are the ones offered themselves to produce the new pcboards layout (2)... they are already doing it.
I gonna feed this thread....now you have two videos explaining details and a third video is beeing uploaded to Youtube:
High power Dx for Bass - YouTube
Dx Custom - YouTube
Output board will be made in order for you to cut pieces of it to reduce length and quantity of output pairs..i will give help and follow up for builder in order to them to adapt the amplifier for the VA rating they have at home (transformer), or the ones they can build or buy...so... CUSTOM because of that.
Pirates will be forced to build full power .... 20 transistors...but you do not need to do that.... will be posted adjustment to full power...but for you i can communicate directly via email informing you the modifications you should make to match your special customized needs.
nanabrother@hotmail.com
carlos.eugenio1951@yahoo.com
I am just starting...so, do not make questions about the VA rating and transformer voltage because i have to study each sittuation separatelly and directly via email.
Of course all informs will be posted here to the full power version...so..if people want to copy they will be able..but will not be able to customize.
regards,
Carlos
It is a Dx amplifier for high power (not exactly the same DHR Turbo)...and for bass.
It will be able to work with 2 ohms loads and it is possible to reach 1.3 Kilowatts of RMS output power (0.6% distortion) from 35 to 200 hertz.
I will start trying passive input filter.... no VBE multiplier gonna be used, i gonna use 4 high speed diodes in series and a string of resistors and trimpots.
An extra board will be made to produce two boards, this will help to avoid piracy because will turn pirate's life hard..they will be forced to make two pcboards and interconnect them.... or to produce and sell two boards...expensive thing because too many transistors in the output (maximum of 20 units)
Renato Comerlatte and Juan Vargas (Vargas Mongo) are the ones offered themselves to produce the new pcboards layout (2)... they are already doing it.
I gonna feed this thread....now you have two videos explaining details and a third video is beeing uploaded to Youtube:
High power Dx for Bass - YouTube
Dx Custom - YouTube
Output board will be made in order for you to cut pieces of it to reduce length and quantity of output pairs..i will give help and follow up for builder in order to them to adapt the amplifier for the VA rating they have at home (transformer), or the ones they can build or buy...so... CUSTOM because of that.
Pirates will be forced to build full power .... 20 transistors...but you do not need to do that.... will be posted adjustment to full power...but for you i can communicate directly via email informing you the modifications you should make to match your special customized needs.
nanabrother@hotmail.com
carlos.eugenio1951@yahoo.com
I am just starting...so, do not make questions about the VA rating and transformer voltage because i have to study each sittuation separatelly and directly via email.
Of course all informs will be posted here to the full power version...so..if people want to copy they will be able..but will not be able to customize.
regards,
Carlos
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Here you have the third video, i have already fixed transistors
So, it is matter to run wires, to check circuit, to search for errors and shorts, to adjust and to listen....i gonna do it tomorrow.
Dx Custom - starting to produce it - YouTube
regards,
Carlos
So, it is matter to run wires, to check circuit, to search for errors and shorts, to adjust and to listen....i gonna do it tomorrow.
Dx Custom - starting to produce it - YouTube
regards,
Carlos
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I will try Andrew.... gonna try, but i cannot test it, i can simulate only
Wanna help?... then inform how many output pairs i gonna need to face all that peak power?
Maybe 36 output transistors.... i have not observed that for a while... the amplifier is in prototype moment, so, i am open to suggestions and help.
20 transistors are to be used for more than 20A into 90 Volts (SOA) but for small time...i really have to think a lot to conclude how many will be needed for continuous 1.3 Kilowatt power.
I do not think people will manage to find a transformer good enough to feed this monster..but it is a good idea to make if good to face full power at 2R..... just in case someone manage to install several power supplies in parallel or try a SMPS.... the real world power will be smaller.... people will try smaller voltages and smaller VA ratings for sure...also people may not use 2R...but.... to make it able to face the hard job can be really interesting.
To fully understand what i mean you should view these videos i am producing... a lot of ideas and explanations are there.
Prototype being assembled is only for testing purposes into a range of 300 to 400 watts RMS... to fully understand these details, please, take a lot at these videos you see below in the signature line..others gonna be made soon.
regards,
Carlos
Wanna help?... then inform how many output pairs i gonna need to face all that peak power?
Maybe 36 output transistors.... i have not observed that for a while... the amplifier is in prototype moment, so, i am open to suggestions and help.
20 transistors are to be used for more than 20A into 90 Volts (SOA) but for small time...i really have to think a lot to conclude how many will be needed for continuous 1.3 Kilowatt power.
I do not think people will manage to find a transformer good enough to feed this monster..but it is a good idea to make if good to face full power at 2R..... just in case someone manage to install several power supplies in parallel or try a SMPS.... the real world power will be smaller.... people will try smaller voltages and smaller VA ratings for sure...also people may not use 2R...but.... to make it able to face the hard job can be really interesting.
To fully understand what i mean you should view these videos i am producing... a lot of ideas and explanations are there.
Prototype being assembled is only for testing purposes into a range of 300 to 400 watts RMS... to fully understand these details, please, take a lot at these videos you see below in the signature line..others gonna be made soon.
regards,
Carlos
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The power amplifier diagram is more or less this way
It is in the prototype moment, so, it will be changed in order to obtain the best sound with the smallest possible distortion.
The quantity of output transistors are there only for demonstration purposes, quantity will be available depending your needs (Customized)
regards,
Carlos
It is in the prototype moment, so, it will be changed in order to obtain the best sound with the smallest possible distortion.
The quantity of output transistors are there only for demonstration purposes, quantity will be available depending your needs (Customized)
regards,
Carlos
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Hehehehe.... that defense of pirates was funny... you may be kidding with me.
The big trouble are these movies we are watching last couple of years.... they made pirate looks so nice....ahahahahah!
Piracy is piracy.... it is a kind of robbery....not that interesting, not that good actually... when making poor copies it is much worse.
Well...no problems... each one of us with our own values, thoughts and beliefs...we have room to everybody in this world.... even Iran guys says things that makes sense.
Parameters?.... attenuation to frequencies upper 250 hertz... to my taste gonna be better upper than 200 hertz (i hate 250 hertz and i love 35 hertz).
For subwoofer amplification... only for Bass.... a kind of earthquake generator.
The amplifier is there.... waiting to be finished and tested...gonna do it tomorrow... i am already tired...temperature here is 29 celsius.
regards,
Carlos
The big trouble are these movies we are watching last couple of years.... they made pirate looks so nice....ahahahahah!
Piracy is piracy.... it is a kind of robbery....not that interesting, not that good actually... when making poor copies it is much worse.
Well...no problems... each one of us with our own values, thoughts and beliefs...we have room to everybody in this world.... even Iran guys says things that makes sense.
Parameters?.... attenuation to frequencies upper 250 hertz... to my taste gonna be better upper than 200 hertz (i hate 250 hertz and i love 35 hertz).
For subwoofer amplification... only for Bass.... a kind of earthquake generator.
The amplifier is there.... waiting to be finished and tested...gonna do it tomorrow... i am already tired...temperature here is 29 celsius.
regards,
Carlos
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testing.
try driving a 1r0 test load for two seconds. That is not as stressful as driving a 2ohm speaker.
If the test results for the 1r0 load are good, then consider testing into a 0r7 for two seconds.
If the results are good then you can proceed with trying to establish the de-rated SOAR for reactive speaker loadings of 2ohms.
try driving a 1r0 test load for two seconds. That is not as stressful as driving a 2ohm speaker.
If the test results for the 1r0 load are good, then consider testing into a 0r7 for two seconds.
If the results are good then you can proceed with trying to establish the de-rated SOAR for reactive speaker loadings of 2ohms.
Dear friends, i have decided to give up related this amplifier
I have found it is not producing the power i want...the efficiency is too much low, despite the sonics are awesome.
Even considering my 90 volts supply has huge voltage drop under load (drop to 73 volts when draining 400 watts from the supply)... i do think it should transfer more power to the speaker/load.
I have tried all i know.... modifications into currents, voltages, style of VAS, i have use three different VAS circuits, modifications into driver currents and output stand buy current...input modifications, gain modification...and no way to increase efficiency.... also all transistors where replaced several times in order to achieve more amplification.
I am uploading a video, as i have tested the unit this early morning and it is already operating as friends will come to the burial celebration of this unit that was considered not good to continue alive.
I thank you all by the posts, messages and emails, but after you spend several hours trying, we should decide to stop to try to have milk from stones.... this circuit i have made, this modified Dx amplifier, operating with 90 volts supply, have not produced the power i was supposing it would produce.... i could go to 190 watts RMS only..when my wish was to go to 300 - 350 watts.
Video is being uploaded showing something and reporting that i give up....not approved!
By the way..thank you Andrew T.... sadly the amplifier was not approved, but i read your tip and it was memorized to be used next time.
regards,
Carlos
I have found it is not producing the power i want...the efficiency is too much low, despite the sonics are awesome.
Even considering my 90 volts supply has huge voltage drop under load (drop to 73 volts when draining 400 watts from the supply)... i do think it should transfer more power to the speaker/load.
I have tried all i know.... modifications into currents, voltages, style of VAS, i have use three different VAS circuits, modifications into driver currents and output stand buy current...input modifications, gain modification...and no way to increase efficiency.... also all transistors where replaced several times in order to achieve more amplification.
I am uploading a video, as i have tested the unit this early morning and it is already operating as friends will come to the burial celebration of this unit that was considered not good to continue alive.
I thank you all by the posts, messages and emails, but after you spend several hours trying, we should decide to stop to try to have milk from stones.... this circuit i have made, this modified Dx amplifier, operating with 90 volts supply, have not produced the power i was supposing it would produce.... i could go to 190 watts RMS only..when my wish was to go to 300 - 350 watts.
Video is being uploaded showing something and reporting that i give up....not approved!
By the way..thank you Andrew T.... sadly the amplifier was not approved, but i read your tip and it was memorized to be used next time.
regards,
Carlos
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Hi carlos,
According to my calculations. 20Pairs is a good number.
Have a look at the pictures, calcutions are done with:
==> heatsink temperature is 50degrees
==> phase angle at load at 2ohm is 35degrees
My
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use a bigger traffo or try classG or H instead....with classAB you are definitely limited to efficiency of about 64~70%
if you wish for 350watts per channel, then your power traffo should be able to give a secondary power of at least 1100watts, your primary should have a capacity of about 1500volt amperes....if you use such traffo, you will get your dream come true...
Thank you by your comment dear Tony
I am uploading videos...here some images about the Dx Custom prototype.
Here you have a sample of it's sonics:
http://www.youtube.com/watch?v=DQYUaAYcqqI
Not approved!
regards,
Carlos
I am uploading videos...here some images about the Dx Custom prototype.
Here you have a sample of it's sonics:
http://www.youtube.com/watch?v=DQYUaAYcqqI
Not approved!
regards,
Carlos
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Dx Custom project give up
Here you have a video that explains:
Dx Custom not approved! - YouTube
regards,
Carlos
Here you have a video that explains:
Dx Custom not approved! - YouTube
regards,
Carlos
It took 2 Dunlap Clarke 120 vct transformers to get 750 watts with 80,000 ufarads on each 120 rail. Had to bring it up with a 25 amp variac too. The DC trans where from the 1000 amp. If my memory serves me, I think each one weighed about 30 or 35 pounds. The one in your pictures is no where near as big as the ones I used.
The one at the picture is a 500 watts unit...no more than that
Used only for testing purposes... of course i do not think it can produce high power.... for more than kilowatt we need a really big transformer that measures 2/3 of a small car battery (36Ah)
Also observe i have used only 6 transistors, because i know the transformer cannot put too much power out...the real thing should have 20 transistors or even more than that.
I understand you may think i am crazy trying to have this power from a so small transformer, the reason why is because this thread is new and some informations and ideas about this amplifier (Dx high power unit for bass) was published in the Dx amplifier thread and you may have not readed.
Uncle Charlie is making amplifier these last 52 years, and a couple of thousand units where produced.... for sure uncle is not dumb this way.
People should read more before to post things.... because just watching a picture will be confused not knowing the details about.... it is often used to feed high power amplifier with a small supply during testings, when we do not know if has a mistake in the prototype construction of not..the presence of a small transformer does not mean we gonna use that toy in the real thing.
I am still having fun..... the power was not approved...the efficiency was not good...but sound is fine:
http://www.youtube.com/watch?v=lQc0Xe43f-8
regards,
Carlos
Used only for testing purposes... of course i do not think it can produce high power.... for more than kilowatt we need a really big transformer that measures 2/3 of a small car battery (36Ah)
Also observe i have used only 6 transistors, because i know the transformer cannot put too much power out...the real thing should have 20 transistors or even more than that.
I understand you may think i am crazy trying to have this power from a so small transformer, the reason why is because this thread is new and some informations and ideas about this amplifier (Dx high power unit for bass) was published in the Dx amplifier thread and you may have not readed.
Uncle Charlie is making amplifier these last 52 years, and a couple of thousand units where produced.... for sure uncle is not dumb this way.
People should read more before to post things.... because just watching a picture will be confused not knowing the details about.... it is often used to feed high power amplifier with a small supply during testings, when we do not know if has a mistake in the prototype construction of not..the presence of a small transformer does not mean we gonna use that toy in the real thing.
I am still having fun..... the power was not approved...the efficiency was not good...but sound is fine:
http://www.youtube.com/watch?v=lQc0Xe43f-8
regards,
Carlos
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