DX Amp
Hartono
At the risk of beingf off topic, I do believe that what you are saying is correct. Proving it conclusively, is a different matter.
Carlos
Perhaps you could see if you can find a way to further refine the crossover area of DX, without copying Hugh's circuitry ?
Graham Maynard will probably have some good ideas to share with you?
SandyK
Hartono
At the risk of beingf off topic, I do believe that what you are saying is correct. Proving it conclusively, is a different matter.
Carlos
Perhaps you could see if you can find a way to further refine the crossover area of DX, without copying Hugh's circuitry ?
Graham Maynard will probably have some good ideas to share with you?
SandyK
Hi Juergenk
"the pushpull stage operates more and more in class a, reducing crossover artefacts."
my example is for underbiased class B
anyway we agree on the same thing, I also agree about the class A you mentioned.
"What happens in the DX-Amp below noise?"
I'm sure Carlos is pretty smart about his DX amp. I was refering to IC amp before. anyway..........we agree on the same thing which is .....good.......
Hartono
"the pushpull stage operates more and more in class a, reducing crossover artefacts."
my example is for underbiased class B
anyway we agree on the same thing, I also agree about the class A you mentioned."What happens in the DX-Amp below noise?"
I'm sure Carlos is pretty smart about his DX amp. I was refering to IC amp before. anyway..........we agree on the same thing
which is .....good.......Hartono
This discussion depends upon how anyone TESTS an amplifier, because loudspeaker current is NOT resistively linear with voltage.
You can have near immeasurable THD across a resistor, but poor reproduction via a LS.
You can have 1% distortion across a resistor, but most satisfactory LS reproduction.
Biasing can affect the response speed of a class-AB output stage within the closed NFB loop. The NFB can reduce errors but not remove them.
I cannot advise Carlos on bias circuitry. This is a compromise that is fundamental to all class-AB amplifier circuitry, so I wonder what might be achieved (or degraded) by doing so.
There is always a compromise between efficiency, bandwidth and reproduction.
PROOF ???
Move your loudspeaker into another room. Listen to your amplifier output via headphones. Listen to the increased loudspeaker induced distortion as you switch the amplifier loading between resistor and remote loudspeaker !!!
Cheers ........... Graham.
You can have near immeasurable THD across a resistor, but poor reproduction via a LS.
You can have 1% distortion across a resistor, but most satisfactory LS reproduction.
Biasing can affect the response speed of a class-AB output stage within the closed NFB loop. The NFB can reduce errors but not remove them.
I cannot advise Carlos on bias circuitry. This is a compromise that is fundamental to all class-AB amplifier circuitry, so I wonder what might be achieved (or degraded) by doing so.
There is always a compromise between efficiency, bandwidth and reproduction.
PROOF ???
Move your loudspeaker into another room. Listen to your amplifier output via headphones. Listen to the increased loudspeaker induced distortion as you switch the amplifier loading between resistor and remote loudspeaker !!!
Cheers ........... Graham.
Bellow the noise floor is also a little bellow my interests.
I am searching for sonic modifications, sound stage deepness (perception and the origin of that into an amplifier...or...what translates into deepness...the reasons, the stages, the causes).
The amplifier sounds fine into the comparisons i have made....yeah!...loose here or there...but also show superiority in something.
I think it distorts too much early..... i can perceive something already strange when power goes up ..... i am trying bigger clean power...but i am perceiving that behavior, the same performance in many others too.
It is possible that i am dreaming too much....as amplifiers normally do not play with the same quality when reproduce class A (1 watt)
compared with 35 watts rms, for instance.
But some subtle (sútil) details.... well...sorry folks.... i left this to those guys loves to observe instruments..... i have used them as tools, and they are not more than tools to me...when working, into Power RF transmitters alignment i use to watch the spectrum analiser to reduce those harmonics intensities...but after that i prefer to watch the image.... not to waste energy into harmonics is the focus in my work.
Also i use to apply the same idea to sound..... i prefer to listen to the music, and instruments are used only when hardly needed...to debug defects...not those subtle things.
I do not want to make my amplifier so good as Aksa...also i am not able to do, and i think that a try to offer something so good as Aksa, and for free..is something absurd to my character... i am not able to behave this way.. He is a friend, was my teacher in many moments, a brother..someone to trust.
I do not want to create any problems to him..... and i love that i could not make Dx amplifier so good as Aksa.... this shows me Hugh Dean value.
If i had discovered, something able to beat Aksa... the unit would be keept in secret, to produce a business, to offer Hugh or to my own pleasure.... a very selfish pleasure, because publishing here would be negative to Hugh sells...well.... in the reality, not one is able, anymore, to disturb Hugh sells and credibility..... his customers are not in the forum, and they are not affected by our ideas...but..for precaution i would never try this.
Mine is a non comercial..not a business unit...It is a diy offered, and suggested for free. why to offer a free option better than my dear friend's product, the one teached me a lot of things.... negative!
It is fine...it is OK the way it is...people can tweak and try to modify, under their own decision and risks.
I am Hugh Dean's friend, not an enemy.... offering something better, a non comercial, non business unit...for free..when he ask money for his products...what will I be doing?
regards,
Carlos
...............................................................................................................
Vinyl
It is all rigth...i have readed your post...
thank you,
Carlos
I am searching for sonic modifications, sound stage deepness (perception and the origin of that into an amplifier...or...what translates into deepness...the reasons, the stages, the causes).
The amplifier sounds fine into the comparisons i have made....yeah!...loose here or there...but also show superiority in something.
I think it distorts too much early..... i can perceive something already strange when power goes up ..... i am trying bigger clean power...but i am perceiving that behavior, the same performance in many others too.
It is possible that i am dreaming too much....as amplifiers normally do not play with the same quality when reproduce class A (1 watt)
compared with 35 watts rms, for instance.
But some subtle (sútil) details.... well...sorry folks.... i left this to those guys loves to observe instruments..... i have used them as tools, and they are not more than tools to me...when working, into Power RF transmitters alignment i use to watch the spectrum analiser to reduce those harmonics intensities...but after that i prefer to watch the image.... not to waste energy into harmonics is the focus in my work.
Also i use to apply the same idea to sound..... i prefer to listen to the music, and instruments are used only when hardly needed...to debug defects...not those subtle things.
I do not want to make my amplifier so good as Aksa...also i am not able to do, and i think that a try to offer something so good as Aksa, and for free..is something absurd to my character... i am not able to behave this way.. He is a friend, was my teacher in many moments, a brother..someone to trust.
I do not want to create any problems to him..... and i love that i could not make Dx amplifier so good as Aksa.... this shows me Hugh Dean value.
If i had discovered, something able to beat Aksa... the unit would be keept in secret, to produce a business, to offer Hugh or to my own pleasure.... a very selfish pleasure, because publishing here would be negative to Hugh sells...well.... in the reality, not one is able, anymore, to disturb Hugh sells and credibility..... his customers are not in the forum, and they are not affected by our ideas...but..for precaution i would never try this.
Mine is a non comercial..not a business unit...It is a diy offered, and suggested for free. why to offer a free option better than my dear friend's product, the one teached me a lot of things.... negative!
It is fine...it is OK the way it is...people can tweak and try to modify, under their own decision and risks.
I am Hugh Dean's friend, not an enemy.... offering something better, a non comercial, non business unit...for free..when he ask money for his products...what will I be doing?
regards,
Carlos
...............................................................................................................
Vinyl
It is all rigth...i have readed your post...
thank you,
Carlos
Lets go....
HI, Carlos!
I have read almost all posts about dx amp and symasym4/5.... I want to build it (dx)
Could you, please, send me eagle files? I am using mill machine for pcb's.
I have already built one amp, but there is a problem with midrange... bass is great and treble beautiful ... but at mid it is something like raining. As I am a beginner in electronics I better create something that is tested
http://www.diyaudio.com/forums/showthread.php?s=&threadid=103710
Thanks!!!
I will use 25-0-25 power supply...
HI, Carlos!
I have read almost all posts about dx amp and symasym4/5.... I want to build it (dx)
Could you, please, send me eagle files? I am using mill machine for pcb's.
I have already built one amp, but there is a problem with midrange... bass is great and treble beautiful ... but at mid it is something like raining. As I am a beginner in electronics I better create something that is tested
http://www.diyaudio.com/forums/showthread.php?s=&threadid=103710
Thanks!!!
I will use 25-0-25 power supply...
Microp..... i have a defect... i use to talk true, sometimes this is understood as
rude.... that i am rude.
Well.... i am already too much old to control myself in such way.
Meeting (virtual) made with all Dx group.... including constructors, decided not to stimulate, not to make easy, not to help too much modifications.
Why that?
We had observed other threads...something i was dreaming as a very good thing turn a nightmare to my point of view..... other amplifier with
many options...was Symassym....now a days Michael has not control of his creation, there are modifications that do not cooperate with sonic quality and he could not avoid.....he gave eagle files...he made this easy.
I read people complaining...was just one...but one is enougth to teach us.... someone modified the amplifier...resulted not good, and Michael was blamed..when the amplifier made is not Symassym anymore.
Not giving Eagle files... at least the boards will not be exactly the same.... will be another amplifier...another option...people will not have the chance to Blame me or my group of friends.
Many folks asked this into direct mail.... you made different.
Eagle files will not be open.
By the way Microp.... if you are able to construct Symassym, if you decided to use all those parts...well.... better to forget Dx amplifier as Symassym has better dinamics and better voices, also better bass... loose for treble only...so... if you have doubts..... Symassym is a better option....Dx is simple and cheap...not needing those things....Symassym can be considered one step up!
regards,
Carlos
rude.... that i am rude.
Well.... i am already too much old to control myself in such way.
Meeting (virtual) made with all Dx group.... including constructors, decided not to stimulate, not to make easy, not to help too much modifications.
Why that?
We had observed other threads...something i was dreaming as a very good thing turn a nightmare to my point of view..... other amplifier with
many options...was Symassym....now a days Michael has not control of his creation, there are modifications that do not cooperate with sonic quality and he could not avoid.....he gave eagle files...he made this easy.
I read people complaining...was just one...but one is enougth to teach us.... someone modified the amplifier...resulted not good, and Michael was blamed..when the amplifier made is not Symassym anymore.
Not giving Eagle files... at least the boards will not be exactly the same.... will be another amplifier...another option...people will not have the chance to Blame me or my group of friends.
Many folks asked this into direct mail.... you made different.
Eagle files will not be open.
By the way Microp.... if you are able to construct Symassym, if you decided to use all those parts...well.... better to forget Dx amplifier as Symassym has better dinamics and better voices, also better bass... loose for treble only...so... if you have doubts..... Symassym is a better option....Dx is simple and cheap...not needing those things....Symassym can be considered one step up!
regards,
Carlos
I think you will have to use turbo version...
http://www.diyaudio.com/forums/showthread.php?postid=1136293#post1136293
http://www.diyaudio.com/forums/showthread.php?postid=1136293#post1136293
Hi microp.
You wrote >>at mid it is something like raining. <<
??????? Thinking cap is on here.
Output induced oscillation ?
Have you kept all VAS output, all output stage and LS wires well away from input circuitry and the input differential transistors ?
What is your LS ? ( I ask in case the present construction cannot cope with either crossover or driver current demands.)
Cheers ......... Graham.
You wrote >>at mid it is something like raining. <<
??????? Thinking cap is on here.
Output induced oscillation ?
Have you kept all VAS output, all output stage and LS wires well away from input circuitry and the input differential transistors ?
What is your LS ? ( I ask in case the present construction cannot cope with either crossover or driver current demands.)
Cheers ......... Graham.
Very good Microp.... the schematic you can see in Greg website
Those Dx pages are updated.
Good to have young and handsome folks doing Dx....ahahahah
this promotes my amplifier.
"Now Dx amplifier is creating interest into young folks too!"
Also:
"Dx is beeing used together switching supplies into automobile"
Very good!
I will watch into the simulator some modifications to a higher voltage version to my friend.
regards,
Carlos
Those Dx pages are updated.
Good to have young and handsome folks doing Dx....ahahahah
this promotes my amplifier.
"Now Dx amplifier is creating interest into young folks too!"
Also:
"Dx is beeing used together switching supplies into automobile"
Very good!
I will watch into the simulator some modifications to a higher voltage version to my friend.
regards,
Carlos
Attachments
Thank you Nordic, as you have shown us your finished enclosure
Very good Nordic....Dx amplifier is playing very happy in South Africa.
Riche.... in some minutes i will check your modifications.
Good Microp, now Dx amplifier has constructors that have a face too....ahahahha.... i think the first one that had courage to post.
Courage is something apreciated by your friend Destroyer x.
Have a personal name too Microp...... apreciate also that you do not accept obstacles.....not having data you jump to make it by youself.
Congratulations Microp...you are a man!
regards,
Carlos
...............................................................................................................
Graham
He had problems with an amplifier he constructed in early past.... in his post you can have the link to that schematic.
It was not a problem with Dx amplifier..... we have great midrange!
regards,
Carlos
.............................................................................................................
I feel happy when people go constructing my amplifier.... thank you folks.
Dx Corporation thank you all by the kind preference.
My happy picture during a very serious celebration...ahahahha
regards,
Carlos
Very good Nordic....Dx amplifier is playing very happy in South Africa.
Riche.... in some minutes i will check your modifications.
Good Microp, now Dx amplifier has constructors that have a face too....ahahahha.... i think the first one that had courage to post.
Courage is something apreciated by your friend Destroyer x.
Have a personal name too Microp...... apreciate also that you do not accept obstacles.....not having data you jump to make it by youself.
Congratulations Microp...you are a man!
regards,
Carlos
...............................................................................................................
Graham
He had problems with an amplifier he constructed in early past.... in his post you can have the link to that schematic.
It was not a problem with Dx amplifier..... we have great midrange!
regards,
Carlos
.............................................................................................................
I feel happy when people go constructing my amplifier.... thank you folks.
Dx Corporation thank you all by the kind preference.
My happy picture during a very serious celebration...ahahahha
regards,
Carlos
Attachments
juergenk said:Hi,
yes, it could be below noise and maybe it's relevant, but as it is never shown in data sheets etc.
So I'm curious, if this claim could be proofed.
regards
Jürgen
Hello
Data sheet show static measurements on dummy load, but on a transient situation on a real loudspeaker the amp will reacted quite differently.
Gaetan
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