Destroyer x Amplifier DX HDII version. - Page 54 - diyAudio
Go Back   Home > Forums > Commercial Sector > Group Buys

Group Buys Members group buys

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 28th December 2007, 07:14 PM   #531
diyAudio Member
 
salesmonster's Avatar
 
Join Date: Aug 2007
Nordic: Did you base your PSU off of the board assembly you are selling?

I was wondering about the 4700uF caps, or if I would see improvement with more capacitance. I know some of the biggest improvements I would get with commercial gear was beefier PSUs. The one that comes to mind would be Naim. They will sell you a really nice product for an arm and a leg...but if you want to unlock the real character of the equipment, that'll be another arm and leg. And for that price, what you got was the PSU they should've sold you to start with. I love the free market system.
  Reply With Quote
Old 28th December 2007, 07:19 PM   #532
Nordic is offline Nordic  South Africa
diyAudio Member
 
Nordic's Avatar
 
Join Date: Sep 2005
The 4700uf caps are sufficient for 50W into 8ohms at least...

I have 1 pair 4700uf and 1 pair 10000uf caps in mine (I had some 10000ufs spare after getting the Panasonic's that fit on the amp PCBs).

Free market is a wonderfull thing, i was looking at using only 'boutique' resistors for some completed modules of the new Precision model... erm well $22 per channel...
  Reply With Quote
Old 30th December 2007, 03:07 AM   #533
diyAudio Member
 
destroyer X's Avatar
 
Join Date: Feb 2004
Location: Recife - Brasil Northeast
Default I could realise, doing, that each ampere will need, at least 4700uf or filter


For instance....one Precision channel have 2 amperes consumption each channel, full power (166 watts over 8 ohms)....this means 2 amperes each rail...and into 8 ohms.

Into 4 ohms you will have 4 amperes each rail.... or something around that..... so.... 20000uf each rail to one channel only.

Having two channels into a single supply, value goes higher... near 40000uf each rail....but this is into 4 ohms.

So.... 20000uf each rail use to fit our needs into Precision.

How this works:

You inject 5 hertz and go with the oscilator volume up till you have unclipped maximum power into 5 Hertz....usually this is very near the maximum into the amplifier i use to make.... 5 Hertz is infrasound.... infrasonic frequencies are not audible...but if you have small condensers...you will listen the hummm into the moments the speaker is into the maximum forward excursion and backward excursion (movement...maximum amplitude)... this means we gonna listen the supply noises...the mains frequency will modulate, will be listened, will be together the maximum power peaks.... i could find that 4700uf each ampere can control that.

But when you increase the voltage... the need will be reducing.

Into 35 volts it is 4700uf...but into 63 i could see it is 3300uf or something around that.

Minimum, to Precision, into 8 ohms... really the minimum to feed two channels using a single supply is 14000uf each rail.... going to 28 or 30 thousand microfarads (uF....means 30 milifarads) each rail to 4 ohms operation.

Is my method precise?

No!...but works.... try and you will see.

regards,

Carlos
__________________
DxS, the best from the best...the cream from the cream, the best wide world ever made audio amplifier.
  Reply With Quote
Old 30th December 2007, 03:19 AM   #534
diyAudio Member
 
destroyer X's Avatar
 
Join Date: Feb 2004
Location: Recife - Brasil Northeast
Default The HRII goes to 2 amperes each rail, maximum power, using 4 ohms loads


Having a single supply feeding two channels, and using 35 to 37 Volts as the supply voltage, you will need 20 thousand microfarads, or 20 milifarads (20.000uF) each rail as minimum!

Of course, increasing it you will have better supply.

This is when you are using a single supply feeding two channels..there are more economical sittuations, for instance, operating with 8 ohms only you will need 10000uf each channel.

When you have series inductor into the supply, you cannot add the condenser you have into each rails, say, inside the supply...because the inductor you will not have those folks added..so.... some overkill, while using inductors in series into the rails are a very good idea.

The reference i am giving you folks...because doing that for long time...and you can check my ideas doing the tests with 5 hertz into the input (big condenser will be used into the input while doing that, because normally 5 Hertz are into -3dB).

1 ampere, till 45 volts will need 5000 uf (4700uf)

1 ampere, from 45 to 63 volts will need 3300uf

1 ampere, from 63 to 100 volts will need 2200uf

Not precise..but works...try it by yourself..never trust me or other folks... the best sittuation for you is to check everything folks say to you...this way you will learn deeply the subject, will never forget and will "really know the whole thing"

Complementary information, about the Dx Standard supply into this adress:

http://www.diyaudio.com/forums/showt...55#post1386655

regards,

Carlos
__________________
DxS, the best from the best...the cream from the cream, the best wide world ever made audio amplifier.
  Reply With Quote
Old 30th December 2007, 03:52 AM   #535
diyAudio Member
 
destroyer X's Avatar
 
Join Date: Feb 2004
Location: Recife - Brasil Northeast
Default Nice work Nordic...congratulatins once again.


Very impressive.... very good.

regards,

Carlos
Attached Images
File Type: jpg very good work.jpg (82.3 KB, 415 views)
__________________
DxS, the best from the best...the cream from the cream, the best wide world ever made audio amplifier.
  Reply With Quote
Old 30th December 2007, 07:53 AM   #536
diyAudio Member
 
salesmonster's Avatar
 
Join Date: Aug 2007
Default Electrolytic Caps

When choosing the electrolytic caps for this amp (and power supply), is the amp very sensitive to what type of caps are used?

I'm considering the Nichicon VR and VZ series. I have heard good things about the Panasonic caps as well. Is this even worth worrying about for this amp? Also, as I build up the power supply, I'm looking at the possibility in using it to feed the Dx Precision.

Dave
  Reply With Quote
Old 30th December 2007, 08:32 AM   #537
diyAudio Member
 
destroyer X's Avatar
 
Join Date: Feb 2004
Location: Recife - Brasil Northeast
Default People said Panasonic is special.


In my point of view they are all the same.

My choice is how they look, how big they are and how much they cost.

But, i can be wrong.....so... go to Panasonic, a lot of people say they are excelent.... some folks said they sound good...i have put one into my ear and i could hear nothing..ahahahahahah.

They will say i am deaf and idiot...no problems, i use to say they are crazy!!!

regards,

Carlos
__________________
DxS, the best from the best...the cream from the cream, the best wide world ever made audio amplifier.
  Reply With Quote
Old 30th December 2007, 08:57 AM   #538
Nordic is offline Nordic  South Africa
diyAudio Member
 
Nordic's Avatar
 
Join Date: Sep 2005
Well I guess you can use anything... the limit is basicaly the cap's diameter... I am useing Panasonic TSUP 10000uf, as it was one of the few caps I found to fit in the space... (25mm)

They were about $30 for 4. (i.e. more expensive than the PCBs)

You could do like Carlos, and build it with smaller caps... it will still work...
  Reply With Quote
Old 2nd January 2008, 04:05 PM   #539
diyAudio Member
 
Join Date: Jun 2004
Location: Champaign, Illinois
Default Mounting power transistors

As a former tube amp builder I have a practical question for the experienced HRII builders. How are you gents/ladies mounting your power transistors to the heat sink?

I started drilling and tapping 4-40 screw thread into the sinks, but it takes a long time! Is there an easier technique I'm not aware of?

Thanks,
Francois
  Reply With Quote
Old 2nd January 2008, 04:17 PM   #540
diyAudio Member
 
meanman1964's Avatar
 
Join Date: Oct 2006
Location: Belgium the land of chocolate
I always use self-tapping srews.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



New To Site? Need Help?

All times are GMT. The time now is 06:44 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2