Dx Super A - MKII - The most awesome audio amplifier i have ever made

[destroyer x]

Playing with the Dx Super A power supply

It is not ready, not adjusted, not tuned, not optimized...i have made it based in reminds of the seventies....values may change...now playing.

regards,

Carlos[video=youtube;m4pFHP2C3Io]http://www.youtube.com/watch?v=m4pFHP2C3Io[/video]

 

[destroyer x]

I will now try to post pdf images about the pcboard

This is to the Dx Super A.

regards,

Carlos

 

[destroyer x]

We are also preparing a pcboard for a huge analogue supply

A series pass voltage regulator.... a stabilized power supply that you can adjust your output voltage from the 15 volts (or less if you change the zener value) to full input voltage.... it is symetrical and very stable.

Voltage drop is 0.1 volt when you adjust it to 30 volts and drain 6 amperes each rail.

Electronic filter is awesome..then we use the 3300uf microfarad capacitance multiplier unit to Class A operation and Super A operation...but when we connect a class AB audio amplifier that needs a fast correction of voltage, then we use 220uf in the place...you see both in the schematic..but we use one or other, depending our needs, and a switch or a jumper make the job to use one or other.

The supply voltage entering the circuit comes from 400 watts transformer with 30 plus 30 AC output... a 400VA power transformer.

regards,

Carlos

 

[destroyer x]

This circuit is the Dx Super A tweaked to operate with 700mA to each rail

This results in 5.5 watts RMS to each channel in pure class A...then if you increase the volume it goes to 40 watts RMS maximum with a very low harmonic distortion and lovely harmonic distribution that reduces the third harmonic (the annoying one)

The Dx Supply posted use heatsinks into the series pass output power transistors.

This circuit you see attached works with 700mA each rail and feeded by 30 plus 30 volts from the Dx Supply that filters enougth for you not to have noises or hum in your output.

You see 42 volts printed..but this is if you will use the standard Dx Super A adjustment of 250 mA per rail...if you increase the current you should reduce the voltage in order to protect the output transistors....because of that i have produce the Dx Supply.... it avoids you to buy 100 thousand plus 100 thousand microfarads capacitors that is usual to class A audio amplifiers filtering the supply against hum.

regards,

Carlos

 

[destroyer x]

Juan have ordered 10 boards by a very high price

Not only because only 10 pcboards increases a lot the price, but also because he ordered special copper thickness, special fiberglass thickness, gold plating somewhere, special paint, double colour silk screen and a lot of things that does not represent increasing in sound quality but increased the price a lot.

Reason why he will pay 28 USD to each board..when could have much lower price if he ordered 100 units or 200 units and without so many features.

I told him to sell them by 18 USD that was the cost to the Supercharged blue boards offered in several foruns wide world...so..he will have this loss of money.

Well...he do not even want to sell...he is in love with his boards..but if you want to give a try, the write to him.... these boards will disappear as soon he publish pictures....will be a matter of a couple of hours...so, make your reservation if you want one or two.

vargasmongo@gmail.com

regards,

Carlos

 

[MicrosiM]

Carlos,


How to sign in for PCBS?

 

[destroyer x]

Go direct to Juan Vargas

He is the one will have samples in a matter of days... adress in previous post.

Soon we gonna have boards Made in Brazil by Zimmer too... also a direct contact:

imap.eletro@gmail.com

Newton wil test the layout today and gonna post a video about it.... Newton youtube adress is in this video channel.... video is not from Dx Super A, but you can have the adress and subscribe to see the future video.

Carlos[video=youtube;Rrh0lpc_Jy0]http://www.youtube.com/watch?v=Rrh0lpc_Jy0&feature=plcp[/video]

 

[destroyer x]

Thos one is in the process to be modified to Dx Super A

You see the big supply transformer and the fan blowers.

Made in Brazil....this guy repairs automobile

regards,

Carlos

 

[destroyer x]

We call the pcboard order back

We decide to put big resistors as protective... 20 watt big units that looks alike a torpedo launcher or second world war.

I will look agressive this way...and we can put the fuses below the pcboard.

regards,

Carlos[video=youtube;peiTg7qFTCU]http://www.youtube.com/watch?v=peiTg7qFTCU[/video]

 

[destroyer x]

Sadly we have no room in the board to a big torpedo launcher

So, we gonna install a smaller one.

regards,

Carlos

 

[destroyer x]

Series protective resistor must be 10 ohms or less

Please, be aware you can destroy your power amplifier...do not use 100 ohms series protective resistor..watch this video.

regards,

Carlos[video=youtube;j6aUIJElJcc]http://www.youtube.com/watch?v=j6aUIJElJcc[/video]

 

[destroyer x]

Adjustment setup

Image.

Carlos

 

[destroyer x]

Much better image from Juan Vargas (Porto Rico)

These yellow multimeters, from China, cost 5 USD here in Brazil...and they are not bad..they are very good!

regards,

Carlos

 

[destroyer x]

Dx Super A adjustment.... thermal issues...thermal drift

Heatsink issues, fan blower..what to do and what not to do.

I hope you enjoy....i know my english is not good..but i did my best to communicate with you all.

regards,

Carlos[video=youtube;jykB_ayiXM4]http://www.youtube.com/watch?v=jykB_ayiXM4[/video]

 

[destroyer x]

Text about adjustment.

regards,

Carlos

 

[destroyer x]

Images to etch at your home were not correctly mirrored...now you have both options

To install componentes into the top of the copper side or using the traditional method througth holes (components at silk screen side and copper track in the opposite side)

Now you have all you need to build by yourself in a cheap way...all explanations given...all tested.

I will also provide you two guys that will produce pcboards to sell at low price (low profit)...one in Porto Rico (North America) and other in the South of Brazil.

You multiply the AC voltage you have in a transformer by 1.41 and then you will know your resultant DC voltage after rectification and filtering...this way a 30 plus 30 volts AC transformer, after rectification and filtering will result in 42 plus 42 volts..or + 42Volts, ground and -42 Volts.

Soon i will confirm their adresses to you.

regards,

Carlos

 

[destroyer x]

Two guys willl provide pcboards.

One is Juan Vargas from Porto Rico (photo attached)... his adress is:

vargasmongo@gmail.com

Another one is Zimmer from South of Brazil...his adress is:

imap.eletro@gmail.com

Make contact direct with them.

regards,

Carlos

 

[destroyer x]

I am etching at home to be sure the board layout is fine

This way you will be sure you can trust in this pcboard.

regards,

Carlos[video=youtube;C_BH0OuqRmU]http://www.youtube.com/watch?v=C_BH0OuqRmU[/video]

 

[destroyer x]

My friend Newton is also testing

Here you have it

regards,

Carlos[video=youtube;DDTcJbVN1Lw]http://www.youtube.com/watch?v=DDTcJbVN1Lw&feature=g-subs-u[/video]

 

[destroyer x]

Juan's layout for home etching was tested

and approved!

regards,

[video=youtube;i-BR5catK_M]http://www.youtube.com/watch?v=i-BR5catK_M[/video]

Carlos