Dx Blame MKIII - Builder's thread

destroyer x

Compulsive builder
Good news Harmonic...enjoy your amplifier the same way our friend Juan Vargas did

He replaced a bad moment (that blue screen in windows) to a pleasure.

Fuse burned means you have power...replace it and go ahead ...with a bigger one is a good idea.

regards,

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

destroyer x

Compulsive builder
Vargas Video.. a shorter version

better.

regards,

Carlos[video=youtube;4T-7A9ttQd8]http://www.youtube.com/watch?v=4T-7A9ttQd8&context=C283baADOEgsToPDskKFra8oKRNCf9IajCKzy5Rj[/video]
 

jhon1977

New member
gud eve how can i use a transformer without CT. in my dx amplifier have a schematic for this type of power supply without CT
 

MicrosiM

Administrator
Staff member
Assembling my DX PCBs!

Just started to assemble my DX amplifier PCBs., that will be tested with my commercial Pre Release Cobra12000 SMPS.

I will include all videos and pictures when I make all tests, picture of SMPS and DX Pcbs is here.

Looks like there will be so much fun!

SMPS is capable of delivering high currents at any voltage range. I pulled 16A at +-63VDC from +-75VDC

Thanks Carlos

DSC01770.jpg DSC01771.jpg
 

destroyer x

Compulsive builder
Yes, you can use 75 volts Sami

But some care will be needed related the electrolytic condenser insulating voltage...you will need to replace the original ones (suggested) by other units with higher voltage rating...maybe 84 volts or more.

regards,

Carlos
 

destroyer x

Compulsive builder
You may need two transformers

First transformer secondary you put a label A and B... second transformer secondary wires you put label C and D.

Now join B plus C... this gonna be your center tap

Now you have three wires.... A, B plus C and D

Your transformer AC output voltage must be aproximately 23 volts output..then you gonna have 23 plus 23.... after rectification and filtering you gonna have 64 plus 64 Dc volts.

About the power of each one of these transformers.... well...this you must decide depending your case... as you can use one single transformer to feed two channels, or one transformer to feed each channel (your amplifier, the stereo unit, will have 4 transformers in this case).

You take a look in the power specifications, already published in this thread, and study your own specific case..your speaker power...your speaker impedance.....then you must decide what is reasonable to your home, and all this depends on your decision and depends on your speakers...then, you will conclude the transformer power (VA ratio that means the same as Watts)

Do not use any other trick to "create" or "simulate" a dual supply using a transformer that has only two wires in the output (secondary)... this never works fine.... do not try.

Or you buy, or build a transformer with three wires in the secondary or you use two power transformers to "create" a single unit.

If you need a transformer of 800 watts..then each one of your dual wired secondary transformers must be a 400 watts unit.

regards,

Carlos
 

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MicrosiM

Administrator
Staff member
But some care will be needed related the electrolytic condenser insulating voltage...you will need to replace the original ones (suggested) by other units with higher voltage rating...maybe 84 volts or more.

regards,

Carlos

Thanks carlos for the advice, as we discussed before I will post every thing here
 

MicrosiM

Administrator
Staff member
DX AMP Assembly

More pictures of the DX amplifier assembly!

I have noticed some problems into parts mounting, like holes for 1N4007 diodes, 15R 3W resistor one hole is smaller that the other, I fixed them all without issues!

I do care for nice audio quality only!

DSC01758.jpg DSC01778.jpg DSC01776.jpg DSC01777.jpg DSC01759.jpg DSC01775.jpg
 

MicrosiM

Administrator
Staff member
DX Amplifier sounds incredible, Robust, 10000% Natural Sound

CARLOS!

Friend Carlos, Since my first power on of the DX amplifier, I cannot stop playing music!

Whats this sound? I am using a very cheap speaker !!!! and I really cannot stop playing music for 2 hours until now!

Now I admit, the best amplifier I have EVER listend to is the DX Amplifier.

Video below shows DX connected to Cobra12000 SMPS, I cannot hear noise at all. you can see video while camera is close to the speaker and NO noise at all.
however, carlos is the one who decide if SMPS can be used or not with his Amplifier.

I am really surprized with sound quality!

Thank you Carlos, really thank you.

[video=youtube;Z5thoMAdqqI]http://www.youtube.com/watch?v=Z5thoMAdqqI&feature=youtu.be[/video]
 

meanman64

Member
CARLOS!

Friend Carlos, Since my first power on of the DX amplifier, I cannot stop playing music!

Whats this sound? I am using a very cheap speaker !!!! and I really cannot stop playing music for 2 hours until now!

Now I admit, the best amplifier I have EVER listend to is the DX Amplifier.

Video below shows DX connected to Cobra12000 SMPS, I cannot hear noise at all. you can see video while camera is close to the speaker and NO noise at all.
however, carlos is the one who decide if SMPS can be used or not with his Amplifier.

I am really surprized with sound quality!

Thank you Carlos, really thank you.

[video]http://youtu.be/Z5thoMAdqqI[/video]

Sami,
Also a very nice build I'm glad you like it my friend.Can you give some information about offset, bias, heat etc
 
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destroyer x

Compulsive builder
I am glad you like it

But please, inspect in the scope if you do not have spurious frequencies from the SMPS being amplified by the power amplifiers.

regards,

Carlos
 

MicrosiM

Administrator
Staff member
Carlos

What about idle current adjustments? Basie?

How to make sure amplifier is in well adjusted

Regards
 

destroyer x

Compulsive builder
Merry Christmas to ll of you and a happy new year

If you are Christian or not this does not matter to me...i wish you a very good time.

Work hard, answer questions.... sorry.... only the next year.

regards,

Carlos[video=youtube;T_fYiWFPC4s]http://www.youtube.com/watch?v=T_fYiWFPC4s&feature=colike[/video]
 

destroyer x

Compulsive builder
I was informed by a builder, that he could listen a humming noise

a very low level hum when he put his ears nearby the speaker.

This amplifier is very well filtered in the earlier input circuits to avoid this...also uses a lifted ground that also reduces noises from the supply.... i have made tests and i could not listen noises..so, i suppose that friend is picking up noises from other nearby sources, or transformers, or mains wiring, or input cable shield, or missing lifted ground connection or too much sensitivity.

Well... even sensitivity i am using a huge sensitivity.... 100 milivolts is all i need to drive my unit to full power..i did that way because i am using some cheap audio source that is low in level ...these mp3/4 players, Ipods and some small gadgets from east.... even this way no noise.

Cranck you volume all the way up and observe that there is no noise... speaker is unfiltered...able to reproduce 60 hertz without losses...and this is my mains frequency.

regards,

Carlos[video=youtube;sEXJj3E1MN4]http://www.youtube.com/watch?v=sEXJj3E1MN4[/video]
 

Marmotus

New member
Dalai ...

If you are Christian or not this does not matter to me...i wish you a very good time.

Work hard, answer questions.... sorry.... only the next year.

regards,

Carlos[video=youtube;T_fYiWFPC4s]http://www.youtube.com/watch?v=T_fYiWFPC4s&feature=colike[/video]

Dear Carlos and all beautiful people,

I've been searching for answers all my life, and I read something that fulfill a big space well within me:
"The Best Religion is a Great Heart" - Dalai Lama

So ... Very Best Wishes For 2012 and all next years to come!!!

Marcelo
 

destroyer x

Compulsive builder
Muchas gracias hermano....thank you brother.

To think using our heart is the best solution....life becomes sweet this way.

Some folks use head to be thinking...others use the lower head...ahahahahah!:D

regards,

Carlos
 

norazmi

diysmps Senior Member
better.

regards,

Carlos[video=youtube;4T-7A9ttQd8]http://www.youtube.com/watch?v=4T-7A9ttQd8&context=C283baADOEgsToPDskKFra8oKRNCf9IajCKzy5Rj[/video]

what the song when he play with alpine speaker? can i have it uncle? nice to meet u here uncle :D
 
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