Great dear Meanman... i am glad you will do it.
Winslow..... yeah...we are all crazy...but happy ones!
Juan is making a layout for it Meanman.... tell me i you need something, some information and i gonna send you.
Are you following my videos?... you are welcome at my channel...please, subscribe there if you are not already subscribed.
Type "Carlos Mergulhão" in the Youtube's address bar.
Image is the layout..not ready yet..... he is doing....video talks about the layout..some instructions to Juan in two languages:
Instructions about pcboards method and rules - YouTube
Carlos
Winslow..... yeah...we are all crazy...but happy ones!
Juan is making a layout for it Meanman.... tell me i you need something, some information and i gonna send you.
Are you following my videos?... you are welcome at my channel...please, subscribe there if you are not already subscribed.
Type "Carlos Mergulhão" in the Youtube's address bar.
Image is the layout..not ready yet..... he is doing....video talks about the layout..some instructions to Juan in two languages:
Instructions about pcboards method and rules - YouTube
Carlos
Attachments
We gonna use a shield against magnetic field interference
because output coil is too much close from some sensitive circuits (second stage)
Then second VAS will use insulator and heatsink will be grounded..this will produce a "wall" a barrier against magnetic field.
regards,
Carlos
because output coil is too much close from some sensitive circuits (second stage)
Then second VAS will use insulator and heatsink will be grounded..this will produce a "wall" a barrier against magnetic field.
regards,
Carlos
Attachments
I do not think we gonna have group buy or even people selling pcboards
by other means.
Juan Vargas just wants to practice pcboard layout design, he will order 4 units , will send two to my home (test purposes) and will keep two with him.
Zimmer, will make another pcboard layout, already doing it, and this one may offer to some local friends as he build the Dx Blame ST (green pcboards) and also the Supercharged (blue boards).
The real thing, dear Meanman, is that we have saturated the diy market in Brasil with these models.... approximately 400 units were distributed and this is more or less the total of "burned fingers" real diy we have..... majority of diyers here are speaker builders and we have some tube builders too.
I have made huge efforts to publish modifications to use these pcboards they already have, not to force them to order new pcboards from us because we are not a business, not a trading group, this is not interesting for us.
Zimmer may offer some units for his close friends...but i am not sure he will do it.
We are entering new Brazilian foruns trying to help to populate them.... and this is the good moment to be in this country foruns, because when new they are real diy foruns...when they became big they became a hidden, a disquise business adress were they use forum to advertised gods to be sold....then the truth becomes twisted on behalf of commercial interests, and DIYers become troublesome as they use to laugh about electrons free copper cables, or zip the dooh dah capacitors together all unobtanium.
There, in these foruns, people are doing by hand (wonderful)..they are etching at their homes, using hot iron to make image transference to copper boards.... the real diyers, the most romantic ones are in charge there.
But for sure we will provide layout to home etching, to photographic etching (photo chemical) and we gonna have gerbers too in order to feed group buys..but really, this is not the target... we know this amplifier is already saturated.
Another thing that happens here, dear Meanman, is that Brazilians feel themselves betrayed because the Dx Blame ST is not the best amplifier anymore..they have built thinking their units would never be exceeded or overcome... but this does not exist, as when a king dies we say...God save the king to the new one... factories use to say that they reserve to themselves the right to make modifications in order to achieve better performance.... because of that i have made modifications, easy to be made in their own pcboards..just replacing, substituting, some few parts.
I swear before God almighty, giving my health, my family and my children as a guarantee that actually, you're going to fall off the chair so you will be surprised with the sound of this amp ... but use recommended parts and do not change any values, also use suggested capacitor values to the supplies and transformer power as indicated.
Here a sample of it's sound performance.. noises from digital camera filtered using software... sound reflections and reverberations absorbed using matresses, pillows and some other resources... was the best recording i have made with it:
http://www.youtube.com/watch?v=X88G02PSp7A
This was digital camera recording...try to imagine how it sounds real life...because these cameras are unable to record a good sound....if sound is good with these trash things (digital cameras)...now imagine how i am listening..how good it is live performance.
I have never had interest to earn money with my amplifiers...now a days much less because i am working for the Government and earning enough to pay all my bills..i cannot buy luxury, but i can go on without worries.... audio is alike a religion to me....money must be out of this equation...we do not pay for a home in heaven and we also do not pay for our pleasure in earth listening good sound.
regards,
Carlos
by other means.
Juan Vargas just wants to practice pcboard layout design, he will order 4 units , will send two to my home (test purposes) and will keep two with him.
Zimmer, will make another pcboard layout, already doing it, and this one may offer to some local friends as he build the Dx Blame ST (green pcboards) and also the Supercharged (blue boards).
The real thing, dear Meanman, is that we have saturated the diy market in Brasil with these models.... approximately 400 units were distributed and this is more or less the total of "burned fingers" real diy we have..... majority of diyers here are speaker builders and we have some tube builders too.
I have made huge efforts to publish modifications to use these pcboards they already have, not to force them to order new pcboards from us because we are not a business, not a trading group, this is not interesting for us.
Zimmer may offer some units for his close friends...but i am not sure he will do it.
We are entering new Brazilian foruns trying to help to populate them.... and this is the good moment to be in this country foruns, because when new they are real diy foruns...when they became big they became a hidden, a disquise business adress were they use forum to advertised gods to be sold....then the truth becomes twisted on behalf of commercial interests, and DIYers become troublesome as they use to laugh about electrons free copper cables, or zip the dooh dah capacitors together all unobtanium.
There, in these foruns, people are doing by hand (wonderful)..they are etching at their homes, using hot iron to make image transference to copper boards.... the real diyers, the most romantic ones are in charge there.
But for sure we will provide layout to home etching, to photographic etching (photo chemical) and we gonna have gerbers too in order to feed group buys..but really, this is not the target... we know this amplifier is already saturated.
Another thing that happens here, dear Meanman, is that Brazilians feel themselves betrayed because the Dx Blame ST is not the best amplifier anymore..they have built thinking their units would never be exceeded or overcome... but this does not exist, as when a king dies we say...God save the king to the new one... factories use to say that they reserve to themselves the right to make modifications in order to achieve better performance.... because of that i have made modifications, easy to be made in their own pcboards..just replacing, substituting, some few parts.
I swear before God almighty, giving my health, my family and my children as a guarantee that actually, you're going to fall off the chair so you will be surprised with the sound of this amp ... but use recommended parts and do not change any values, also use suggested capacitor values to the supplies and transformer power as indicated.
Here a sample of it's sound performance.. noises from digital camera filtered using software... sound reflections and reverberations absorbed using matresses, pillows and some other resources... was the best recording i have made with it:
http://www.youtube.com/watch?v=X88G02PSp7A
This was digital camera recording...try to imagine how it sounds real life...because these cameras are unable to record a good sound....if sound is good with these trash things (digital cameras)...now imagine how i am listening..how good it is live performance.
I have never had interest to earn money with my amplifiers...now a days much less because i am working for the Government and earning enough to pay all my bills..i cannot buy luxury, but i can go on without worries.... audio is alike a religion to me....money must be out of this equation...we do not pay for a home in heaven and we also do not pay for our pleasure in earth listening good sound.
regards,
Carlos
Attachments
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Is the Dx Super A really much better than the Dx Blame ST?
Please, watch this video;
Is Dx Super A really better than the Blame ST - YouTube
regards,
Carlos
Please, watch this video;
Is Dx Super A really better than the Blame ST - YouTube
regards,
Carlos
Juan is making a very pretty board layout
He is improving.
watch this;
Dx Super A Heat sink idea good part 1 - YouTube
regards,
Carlos
He is improving.
watch this;
Dx Super A Heat sink idea good part 1 - YouTube
regards,
Carlos
Juan have finished the pcboard layout
I am sorry, the english audio is missed... software have "eated"...but watch the image..it shows the pcboard layout.
Dx Super A - Madre de dios, esto es perfecto. - YouTube
regards,
Carlos
I am sorry, the english audio is missed... software have "eated"...but watch the image..it shows the pcboard layout.
Dx Super A - Madre de dios, esto es perfecto. - YouTube
regards,
Carlos
My home amplifier, adapted to my own needs.
It is not better than yours..it is just customized to my needs.
My own circuit, to my home use, to my needs, to my supply voltage. - YouTube
regards,
Carlos
It is not better than yours..it is just customized to my needs.
My own circuit, to my home use, to my needs, to my supply voltage. - YouTube
regards,
Carlos
Simulator results can be a HOAX, depending the way you use them
I was using wrong way...one more thing i have just learned.
Simulator can produce a HOAX,if you use resistor as a load - YouTube
regards,
Carlos
I was using wrong way...one more thing i have just learned.
Simulator can produce a HOAX,if you use resistor as a load - YouTube
regards,
Carlos
Ask the wrong question and the simulator will give you the correct answer to the wrong question !!!!!!!!
The simulator operator MUST understand the circuit operation AND must understand how to use the software.
If the operator is missing one of those skills, then there is no hope of asking the right question.
The simulation software will always give the correct answer. It will never give a HOAX answer !
The simulator operator MUST understand the circuit operation AND must understand how to use the software.
If the operator is missing one of those skills, then there is no hope of asking the right question.
The simulation software will always give the correct answer. It will never give a HOAX answer !
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I have just finished to assemble my home unit...the one i have tried to match
using simulator and i have finished to adjust listening....it is playing and i do think anything can be better.... to make it better i have to replace the band that is playing, the audio source.
How can something be better than the perfection?
Soon you gonna have pcboard layout...maybe Zimmer will offer from Brasil some pcboards, but for sure you can make it using the pcboards you already have from the Dx Blame ST and the Supercharged multimodel blue boards.
regards,
Carlos
using simulator and i have finished to adjust listening....it is playing and i do think anything can be better.... to make it better i have to replace the band that is playing, the audio source.
How can something be better than the perfection?
Soon you gonna have pcboard layout...maybe Zimmer will offer from Brasil some pcboards, but for sure you can make it using the pcboards you already have from the Dx Blame ST and the Supercharged multimodel blue boards.
regards,
Carlos
Please, remove this electrolitic condenser
This bothers a lot when we go adjusting as capacitors opposes to voltage variations, it charges and discharges and disturb a lot.
Remove it or install a 100n in place as low values will not bother and will procceed the suck out action too.
regards,
Carlos
This bothers a lot when we go adjusting as capacitors opposes to voltage variations, it charges and discharges and disturb a lot.
Remove it or install a 100n in place as low values will not bother and will procceed the suck out action too.
regards,
Carlos
Attachments
That capacitor is usually there to minimise the AC impedance between the bases.
That minimised impedance then maintains a very low AC voltage between the bases and that allows the output transistors to perform their function.
yes the cap can be varied over a wide range of values.
Some optimisation will probably benefit the amplifier.
But your statement,
Measure the voltage across the resistor/capacitor combination, when the amplifier has no input signal.
Measure the DC voltage and the AC voltage across the resistor/capacitor combination, when a signal is passing.
A scope would be better for measuring this but neither end of the combination is at Earth Potential and this makes for skilled scope use to get a result.
That minimised impedance then maintains a very low AC voltage between the bases and that allows the output transistors to perform their function.
yes the cap can be varied over a wide range of values.
Some optimisation will probably benefit the amplifier.
But your statement,
is nonsense. The capacitor holds a charge set by the dc current through the 180r. The AC signal adds, or subtracts, to that charge when the capacitor is too small to pass the AC signal. When the capacitor has low AC impedance for the frequency being processed the variation in charge across the capacitor is the AC current times the AC impedance. That AC voltage must be low, otherwise the capacitor is too small for the signal being processed.
cannot be the correct solution.
Measure the voltage across the resistor/capacitor combination, when the amplifier has no input signal.
Measure the DC voltage and the AC voltage across the resistor/capacitor combination, when a signal is passing.
A scope would be better for measuring this but neither end of the combination is at Earth Potential and this makes for skilled scope use to get a result.
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Andrew
One purpose of that capacitor is provide an ac low impedance path from say the top output transistor base (npn) to the bottom driver transistors emitter (pnp). The necessity from needing to quickly turn on the upper transistor (sucking out excess base charge) following a large signal positive excursion, by using the active bottom driver.
This action will result in changing the voltage across this capacitor which will then change the effective bias and idle current across the output transistors.
The delta voltage and time required to return to the nominal bias is dependant on the capacitor value, so you end up balancing cross-over distortion (not enough capacitance to turn-off the upper transistor fast enough) and resulting idle current change (to small a capacitor) and the recover to nominal idle current (too large a capcitor).
Same effect on capacitors which shunt any vbe multiplier except for the difference in how these are charged or discharged during large signals.
These two effects made it really hard for me to measure the heating effects of the output transistors following a short large signal response (I was trying to measure the idle current as an indicator of output transistor temperature change).
Thanks
-Antonio
One purpose of that capacitor is provide an ac low impedance path from say the top output transistor base (npn) to the bottom driver transistors emitter (pnp). The necessity from needing to quickly turn on the upper transistor (sucking out excess base charge) following a large signal positive excursion, by using the active bottom driver.
This action will result in changing the voltage across this capacitor which will then change the effective bias and idle current across the output transistors.
The delta voltage and time required to return to the nominal bias is dependant on the capacitor value, so you end up balancing cross-over distortion (not enough capacitance to turn-off the upper transistor fast enough) and resulting idle current change (to small a capacitor) and the recover to nominal idle current (too large a capcitor).
Same effect on capacitors which shunt any vbe multiplier except for the difference in how these are charged or discharged during large signals.
These two effects made it really hard for me to measure the heating effects of the output transistors following a short large signal response (I was trying to measure the idle current as an indicator of output transistor temperature change).
Thanks
-Antonio
It was disturbing a lot Magnoman.
I use to check things into the workbench, with soldering iron in my hands..and there these effects comes true.
Simulator said it was lovely there...that reduced THD..but real life it was driving me crazy... i am returning to my traditional, standard, 100n suck out capacitor.
regards,
Carlos
I use to check things into the workbench, with soldering iron in my hands..and there these effects comes true.
Simulator said it was lovely there...that reduced THD..but real life it was driving me crazy... i am returning to my traditional, standard, 100n suck out capacitor.
regards,
Carlos
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I understand the mechanism you describe.
How does one test for the optimum capacitor value?
The optimum is >> 0pF
How much greater?
Presumably it varies with output devices and with output topology and with stage stability. Roender damped the Cap with 0r82 with good reason, not because he thought it looked pretty. I think it confirms that stability does come into the optimisation.
Yes Juan, back to 100n or 220n..the standard value i had used
these last years.
I am listening the unit... having fun.
Dx Super A - Magnificent. - YouTube
regards,
Carlos
these last years.
I am listening the unit... having fun.
Dx Super A - Magnificent. - YouTube
regards,
Carlos
Dx Super A is flat, say, it is electricaly flat... from 10 to more than 200 kilohertz
Yes, it is...but when you connect to speaker it does not look flat anymore...the sonic signature appears.
It looks that has a gain above 10 kilohertz, and it is not a small gain, in a graphic equalizer it is alike to increase 6 dB all frequencies above 10 kilohertz.
What gonna happens?
People not that skilled will say it has lack of bass...negative!..bass is there, and very powerfull, and moving the speaker and pumping huge ammounts of air, but the high end treble looks so strong that we feel the amplifier has not bass...in the reality, when connected to speakers, it reproduces treble very well an this looks, by comparison that we have no bass.
This is a matter of our reference point.... we can say has not bass or we can say has a lot of treble... depends on your mind precision.
regards,
Carlos
Yes, it is...but when you connect to speaker it does not look flat anymore...the sonic signature appears.
It looks that has a gain above 10 kilohertz, and it is not a small gain, in a graphic equalizer it is alike to increase 6 dB all frequencies above 10 kilohertz.
What gonna happens?
People not that skilled will say it has lack of bass...negative!..bass is there, and very powerfull, and moving the speaker and pumping huge ammounts of air, but the high end treble looks so strong that we feel the amplifier has not bass...in the reality, when connected to speakers, it reproduces treble very well an this looks, by comparison that we have no bass.
This is a matter of our reference point.... we can say has not bass or we can say has a lot of treble... depends on your mind precision.
regards,
Carlos
