Dx Blame ST together Dx Super A

Yes... i did it...this made my day.

Today i gonna have Pizza and Coke....i deserve that.

Join the "Corporation" boys!

We are like an army, to defense your freedom and right to listen a good sound!

regards,

Carlos
 

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Macros will be shared by Juan...he is starting to make our layout

About best amplifier...well... i had several two best ones...the Dx Blame ST and now the Dx Super A ... now a days Dx Super A is in the throne.... i do not know in the future if i will make another one even better...i doubt...but it is always possible.... as anything is perfect.... this is the most perfect i have listened..but i had not better experience.

Give it a try boys.... tell me what you feel about.

Here is the schematic... the final one...will not change anything more.

What we have interesting about it:

It starts operating with 250 mA each rail (around 20 watts of dissipation) and this is keept this way when you go increasing the volume till you reach 6 Watts RMS at 8 ohms..then it leaves the class A operation and goes, slowly, decreasing the DC bias current that become 5 watts of waste energy (dissipation) at 40 watts RMS and goes to 2 watts of waste energy (dissipation) from 60 watts RMS and up... DC bias current will be around 25 miliamperes minimum all time long, even if you operate it above 60 watts RMS... this represents a very small waste of energy.... this is not that important when we will have 1.5 A of dinamic current each rail when the audio amplifier is in operation... this is Super A... a few watts in classe A (no crossover distortion, a very pure sound at normal listening volumes that usually are not higher than 2 watts RMS each channel)... then when we need power, this kind amplifier "switches" to Class AB and the efficiency becomes much better (jumps from 20 to 30 percent to 55 to 65 percent).... so, you will not have the Class A heat, that could be 300 watts of more of heat... in our case you have 20 watts till 6 watts RMS and power dissipation will be less than 150 watts when operating full power.

I will inform power at several impedances... aprox. 77, 150 and 280 Watts RMS to 8,4 and 2 ohms... THD to 8 ohms full power is less than 0.0015%.... frequency response goes flat from 10 hertz to 130 kilohertz..input impedance is 56K.... sensitivity is 750 milivolts peak to full power swing in the output, but this is adjustable in any other condition you want replacing a single resistor... second harmonic is 6 to 7 times bigger than third (and this is great!)... this is tube alike sonics.

Harmonic distribution and some other graphics will be posted soon....but some information about current, transformer power and other details, were already posted in this same thread and will be the same to the Dx Blame Super A, to the Dx Super A and to the Dx Super A - MKII.... say... power needs to transformers, quantity of electrolitic condensers to the supply to 8,4 and 2 ohms and fuses will be the same as the supply voltage is the same (42 plus 42 volts DC)

regards,

Carlos
 

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I know that lineup, the idea is to show the unit is playing

Also to differentiate uncle charlie from other designers that produces only simulator schematics.... i do the whole thing.

I have already explained that to forum folks..the ones use to read my threads know that very well.

Sadly you have not made any new discovery...we all know that.

Build my amplifier and you gonna love me more.

regards,

Carlos
 
You know Lineup... Sweden is go to be frozzen cold

Why don't you buy some air tickets with all that matress filled with money you have at your sleeping room.... why not to open it and remove all this money and come to South America then you will listen uncle charlie amplifier live!

My appartment if here, i can have a room for you and a nice bed....here you will pay only your personnal food if you dislike mine.

A good chance to make an International travell, almost for free.... here is almost summer...girls are almost naked at the beaches and they love green eyes.... you can bring your partner Gromanswe with you.

regards,

Carlos
 

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This amplifier is being offered in Brazilian foruns

We have already two more layout designers for Brasil working on it.

We have distributed, inside Brazilian group buy, 200 kits of Dx Blame ST and now these folks wants to make an update of the previous model to the Dx Super A.

We are working hard informing about the stuff to Brazilians... several videos in portuguese are being posted and almost a hundred messages already have arrived my inbox.

I am happy as my people trust on me...soon we gonna have Dx Super A populating audiophile homes in my place.

Give it a try folks... Satisfaction is guaranteed or i will eat the circuit.

It is the best amplifier i have made....yes, i told that before...but this was before i have listened this one.... my people has forgived me because i have made them build the Dx Blame ST and it was not the best one as have made it even better this time.... i am happy because of that..they will update and upgrade their Dx Blame ST to transform it in Dx Super A.

regards,

Carlos
 

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It starts operating with 250 mA each rail (around 20 watts of dissipation) and this is kept this way when you go increasing the volume till you reach 6 Watts RMS at 8 ohms..
this is impossible.
I had trouble trying to understand your earlier explanations of what you were trying to do. You lost me each time.

This quote proves you don't understand what you are trying to do.

I will explain why the quoted sentence is technically impossible.
A push pull amplifier delivers ClassA output when both transistors are actively controlling the output current.
The ClassA current limit is reached when output current reaches just short of two times the quiescent bias current of the output stage.
Setting the output bias to 250mA then limits the ClassA maximum output current to just short of 500mApk.
Into an 8r0 resistor, this will be equivalent to 0.5*0.5*8/2 = 1W
If you double the load resistor value to 16r then the max ClassA doubles to just short of 2W. If you use a 48r load resistor then the maximum ClassA is just short of 6W, if the output stage can deliver 24Vpk while passing 500mApk through the 48r load.

Are you designing this amplifier for 48ohm speakers?
 
Negative Andrew... simulator said different... also calculations

250mA to each rail means we have more than 20 watts of consumption and almost 35% of that is class A operation...so, calculating you will see we can go to 6 watts.

Problem may be units and numbers, RMS, peak and peak to peak.

Follow my videos and i will show you this dinamically.

regards,

Carlos
 
Boys...here you have some performance reports in two languages

One of them, naturally, english.

I am still working in many things.... mainly listening and replacing (substituting speakers) to check if it sounds good with "any" speaker (the ones i have) as i said before.

Also i am informing Brazilians how to make modifications in their Dx Blame ST green boards in order to make it work Super A.

If calculations are wrong or right, if power is 1 watt or 6 watts...well..this does not matter too much to me, as we can increase and decrease just replacing the zener diode and also adjusting the start up Super A bias current..do not worry, sound is awesome with right or wrong calculations about power...it is possible that Andrew is right as he is very good with calculations... and i am not good... i am good in the practice.... well... after all we can arrange that easy, going to higher power into class A if needed.

You see that there are much more interest to prove "i do not know what i am doing" then to help us to do correct things...calculations are made only to show you are no good...and never to help you to make the correct thing..the idea is to reduce you ... not to help you or the community... so, it is more a personal problem, not a cooperation to the advance of our forum quality.

Here you have the video link to some performance taken from the simulator:

Dx Super A - MKII - Performance - YouTube

A picture of Dx Blame ST, green Brazilian pcboard (some people outside Brasil have them too) with indications of how to modify this board while we are preparing (3 layout designers) new models.

regards,

Carlos
 

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I have to ask again.
What is Super A doing?

I think you have explained that Super A reduces the bias voltage when output voltage rises above a threshold.
Does that apply equally to +ve & -ve thresholds?
If Super A reduces the bias voltage, does that end up with an unbiased output stage?
Does that result in a distorted output signal?
 
I have made a small video about adjustment...and this finishes the hard work

Now i will give attention to the emails that are arriving and help builders...all needed data was posted.

We gonna prepare pcboard layout, and this is my focus now.

Enjoy a nice amplifier guys.... the ultimate high fidelity engine.

Dx Super A ... at least the best wide world, ever made, audio amplifier:

http://www.youtube.com/watch?v=xsdZMMDhJYI

regards,

Carlos
 
I use to post videos in order to explain details about

This way i become rid to be answering questions, one be one when appear some doubt.

The ones watch my videos knows we can put out, at least 4 watts RMS because of 20% efficiency in class A operation.

This way, dear friends, all of you are a very welcome to watch my videos, there you may find the majority of details related specifications, and this way, opened to whole world and not only to diyaudio forum readers.

Questions already answered in my videos, and not directed to my email, will be ignored because already answered, and maybe the guy demand exclusive attention when i have not time to spend that way.... video was made to save my time.... wonderful modern times...we have now a days much more than only text... we have audio and we have video.

nanabrother@hotmail.com

Of course, i will do all i can to answer other details not covered in my videos.

Video production use to be a hard work, takes some time, but at the end result in savings of time not to be discussing a couple of details in several posts...it is all there, and everybody can watch...this use to take hours rendering and uploading...but at the end helps me a lot to be free to make what i like, real world constrution of units and audition tests..this is pleasant to me.

Simulator images proves all i use to say...not to remain any doubt, this way i have anything to discuss or ideas to defend...complains should be sent to the simulator manufacturer.

Audio recordings shows i have really built the stuff.... that i am a real builder and not a simulator man.

So, if you feel confused, and need some attention, you gonna be welcome to my private email adress..here you have another one:

carlos.eugenio1951@yahoo.com

regards,

Carlos
 
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Help uncle charlie to save time...join me at my youtube channel

Just type Carlos Mergulhão in the youtube adress bar and you will be sent to my channel.... almost 500 videos are there about different subjects.

Please subscribe, click the "like" button if you like and the "dislike" button if you dislike, write some comments there ... you will be very welcome.

I have some subscribers but i want more...also some thousand of views...help me to increase...go there please.

No, i do not receive any money from youtube, i am not registered as a partner and there's no payment to me ....i do not want to be included as when we enter the "system" we cannot use songs that have copyright ...i do prefer to be free than to receive a couple of dollares.

regards,

Carlos
 

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