Destroyer x Amplifier...Dx amp...my amplifier

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I may be wrong but it looks more like you are trying to achieve some kind of bass boost by manipulating the gain. There is nothing wrong with the idea.

There are a lot of infomation on the net regarding Linkwitz Raily bass equaliser for countering the natural low frequency roll-off typical to of small sealed enclosures and in so doing tailor the response of your speakers to be flat down to single digit frequencies.

Removing the capacitor in the ground path however is not a advisable as this provide low frequency roll off and hence DC stability.

If you still use LPs, rumble from the turntable could result in the speaker voice coil being damaged when it hits ends or being severely burned when moving out of magnetic field while very low frequencies at high amplitudes are present.
 
You could see one example of what is a "complicator"

People that do not like to make simple or easy.

If we have leakage, better to substitute C1 in the place to install another one to compensate and to keep the leakage one into the circuit.

Strange those things...... or i misunderstood completelly or the guy is a good example of those ones i call "complicators"

Not your Harry3... the one that wrote the text.... what a hell the guy could find a leakage electrolitic condenser!..... i have near 50 years doing those things daily...imagine 50 years multiplied by 365 days...how many condensers i have used.... i found 1 or 2 with leakage.

The writter may be single.... decided not to married because the first boy friend can return one day and stolle the woman from him... also leave into the basement, as some Meteor can fall down.

And this guy worrying, having concerns about this subject... almost unbeliavable!

Very difficult to have leakage, you have to invert them, the condensers, till they turn very hot and spell electrolitic liquid out from the case... the rubber insulations inflates....or you have to use them with very higher voltage than the specifications, and they hold, normally, 30 percent bigger voltage, easy!... also using in audio, you have to force 100 volts peak to peak audio signal crossing it, with one extreme at the source and the other point into a low impedance load.... you have to put power crossing the unit... some 12 volts unit beeing crossed with 100 volts PEP!

When you invert, or when you perceive leakage, or when you usbjected the unit to higher voltage than the maximum specified, the solution is to send it to the garbage can...not to install the unit into amplifiers.

Concerns about electrolit condenser leakage.... this guy may leave under a glass dome afraid of víruses.

This solution seems to me..... i am afraid i misunderstood the point, but if the idea was understood correctly, seems that you have your automobile engine damaged, in the place to fix it, or to replace the engine, you decide to install another engine into the car's hear.

The one will install a ligthning protection inside the enclosure, or to fix the amplifier into the ligthning tower base...as some storm may damage the equipment.

regards,

Carlos
 

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Hi all,
capacitors leak.
Most film types leak so little it can generally be ignored.
Electrolytics leak more than a lot.
So much so that us amateurs can measure the leakage with our poor quality instruments.

Destroyer,
how can you say electrolytics only leak if reverse polarity is applied.
To me your statements are downright wrong.
what a hell the guy could find a leakage electrolitic condenser!..... i have near 50 years doing those things daily...imagine 50 years multiplied by 365 days...how many condensers i have used.... i found 1 or 2 with leakage
Very difficult to have leakage,
you have to invert them, the condensers,
or you have to use them with very higher voltage than the specifications
 
That small leakage do not disturb the amplifier work

Leakage so small that do not disturbs.... some small flows of electrons are hard to call them leakage... you know... small giant is not a giant!

People worry too much with details.... complicators.

I have found 1 or 2... the ones i can remember, and i have worked years into Motorolla Radio Transceivers, and also into audio industries... man!... i have more hours into the real electronics work...burning fingers, than the bees have catching for flowers.

Yes, i can say this is rare.... and now i confirm.

Off course...if you say 300 uA is a leakage is another thing.... i do not think this can disturb.... well...never disturbed, it is just normal, common....not a real defect.... some electrolitc condenser effect only.

Try to construct some amplifiers Andrew.... a good idea, you will check a lot of trues and realities.... suggestion for free to you... what about to join your excelent theorical experience into practical, real work...you will turn a monster into electronics in a matter of 5 years.... will be one of the best, if not the best one!


regards,

Carlos
 

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Hi Carlos,
I emailed you the other article because this site thinks it is larger than 1Meg and will not allow me to post. I think it is only 300K.

As for the above, a simpler solution would be to purchase a low leakage cap. These are made by most manufactures. I believe the Blackgate bi-polar were also low leakage.
 
Hi Carlos,

I am with you on this one.

Yes electrolytics do leak, and it is part of their characteristics, like having a resistor in parallel.

When folks ask as to why not remove the capacitor altogether, how can they complain about having a high value resistor in the same place.

I think the more important possible diasturbance relates to charge/discharge hysterisis, but hey, the value in use should be so large at the AF being discussed, that this effect is also rendered negligible. Only when used for frequency response contouring should this aspect of electrolytic capacitors be considered.

If modern QUALITY electrolytics are used, then electrolytics should not be a problem. I once put a 10,000uF PSU cap charged to 35V on the shelf. Two months later and it had retained sufficient charge to read 25V.

This leakage aspect refers more to old or economy manufacture and worn out components, not to quality components bought new and used in input and NFB positions.

Circuit topology is going to have a much greater impact upon reproduction quality than appropriately using carefully selected and cascaded modern electrolytics.


Cheers ........... Graham.
 
Well....maybe Andrew have found leaky ones.... it is possible

Also the term "leakage" can be applied to huge leakage and small leakage, depends the one that is evaluating.

In my point of view, depending the circuit part... till 1 miliamperes is not something to worry about... we usually pay 100 times more wasting energy to bias amplifiers...so...one more miliampere.... nothing in my point of view...for other folk this may be a scandall.

I have those good ones that keep the charge for long time...also i have wasted some time installing digital meters in series with many condensers i have... a made a construction with aligator clips to evaluate those things.... i found nothing that deserves worries....of course..depending how sensitive is the position, the place to use it, the circuit were the condenser is installed.

Those Black Gates are delicious, i have some from Hugh Dean, and also some that came from Greg Erskine.... always the good Aussies...kind folks...i love all Aussies... will be a surprise to face the bad one.....they may be a rarity in your place Harry3

Well..... bad condensers are something bad as insects...bother a lot...so.... use this drug against them all.

regards,

Carlos
 

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Hi,
I did not make any comment on whether leakage affects sound quality, nor on whether that modification was good or bad or worth trying.

I did comment on the plain untruths in those particular statements.
To me your statements are downright wrong.
quote:
what a hell the guy could find a leakage electrolitic condenser!..... i have near 50 years doing those things daily...imagine 50 years multiplied by 365 days...how many condensers i have used.... i found 1 or 2 with leakage
quote:
Very difficult to have leakage,
quote:
you have to invert them, the condensers,
quote:
or you have to use them with very higher voltage than the specifications
 
IMPORTANT message..... Precision is DEAD!

I made a very stupid error into my comparisons.... and doing once again, having some help i realised that the Precision do not sounds better than the High Resolution.

The Dx Precision sounded WORST than the High Resolution.

So..... Merry Christimas advanced for you all.

The High Resolution II is the best amplifier i could make... and it is the last one... the ones are buying the boards will have not the second one... will have the best i could make.

Enjoy the Dx Standard (sounds very nice too) and the High Resolution II

LOOSE!.... and was clear..... i made a very stupid system to compare.... i am sorry.... i was a very big idiot.... and now, doing once again i found my errors.

No more Dx Precision.... it has nothing precise.... High Resolution have eated the Precision into the breakfast.

My desire was to give you a gift.... a new and better amplifier.... i could not...my competence limits was reached, better ones from others designers...i touched my top ceiling of competence i think.

But i am happy.... true is true.... i was feeling something...when was listening the Dx Standard i felt the difference to the Precision very small....i was starting to perceive that a mistaken was running.

So...enjoy what you have....my Christmas gift to all forum friends.

regards,

Carlos
 
Ag no man, what sad news....

Although what you did is wonderfull....

There are many great amps....
some are very expensive to build, like Alephs
Some need good preamps, like chipamps, and mosfet hybrids etc..
very few is going to deliver this quality sonics for the bucks... Sure you can get more powerfull... but what percentage of the timedo you realy open up your volume all the way... You probably spend 90% of the time with the volume lower than 11 o' clock... and this is where the HRII shines brighter than most.

I realy need a break from all these kits... I have such respect for guys like Brian GT, and the twisted pair guys now, it is incredibly hard work, if you don't just want to count off components and throw them in a bag. I am going to test my HRII at a friend's place (the Liquid Silk guy), he has some awesome DIY threeways, which realy humbles my speakers. Pretty sweet to watch those high excursion drivers wobble at 5Hz tones and hardly hear a thing.

his amp is a valve / mosfet hybrid and tweaked to boredom.... I can't wait to see his face when we compare amps this time....

Last time he won by far whem I brought my chipamp over.... sorry chipamp, I didn't know it was 6 ohm speakers....
 
Sorry Nordic....but let's go to remember details about the HRII

The treble booster capacitor is optional...it can be decreased or even removed if result bad into the constructor system

It increased treble... and goes till 30 Kilohertz, and there the amplification is enormous...will bother rats.... we cannot listen.

But of course, this turns the amplifier less stable...so... start without the capacitor...when everything fine, try it.

The VAS compensation capacitor must start with a 150 picofarads, this is a safe solution... and them, the constructor can go reducing monitoring the output voltage (AC) to see if it oscilates and what value make it oscilate.... finding the smaller value...jump two steps up.

Example....you go reducing and 33 picofarads was not enougth and the amplifier started to oscilate...big voltage (AC) into the output.... zobel condenser and zobel resistance very hot and sound very strange.....than, concluding that 33 was not good..jump two steps up...normally first step is 39 picofarads and second step into commercial capacitors is 47 picofarads.... then try that one...if stable..keep it..... make this test with the treble boost capacitor installed... without it, the amplifier is a hell stable.

regards,

Carlos
 

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Use a 10K trimpot here... there are decisions you can make...for instance

to use resistances into the mirror place.... the transistors you have in the place of differential colector resistances can be removed and substituted by two 2K resistances.

Then...you will feel the need of this trimpot.... 4K7 or 5K trimpot has not too much range to modifications..for sure the 10K is worst to adjust...but i strongly suggest you to start with it...if you perceive your adjustment smaller than 4k7... then, go the smaller trimpot.

regards,

Carlos
 

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