Which LM4780 Kit ? - diyAudio
Go Back   Home > Forums > Amplifiers > Chip Amps

Chip Amps Amplifiers based on integrated circuits

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 2nd February 2011, 08:03 PM   #1
diyAudio Member
 
Join Date: Jul 2010
Default Which LM4780 Kit ?

I have an empty case from a HAFLER SE120 Amp . Nice , big heat - sinks , all required plugs / switches / fuses / wires , etc.

I want to build a pair of LM4780 Kits . I have found two on the web .
One by " AudioSector " for $ 79 , plus shipping from Canada . And ,
another shown on " Chipamp.Com " with no price . The latter seems from the picture to have four discrete diodes included . I had wanted to build my own bridge using the " Semi - Famous " MUR860s .

Not counting the bridge , and saying I use a Plitron 33 or 35 VAC XFMR ,
which would produce the best sound through a " Neutral " loudspeaker ?

TIA , David V. Webber
  Reply With Quote
Old 2nd February 2011, 08:12 PM   #2
diyAudio Member
 
ianpengelly's Avatar
 
Join Date: Oct 2006
The chipamp kits use the MUR860s. Not wanting to be biased, but the Peter Daniels kits are very good value for money and will be made to an excellent standard, so you can't go far wrong with those. I am not sure there will be much difference in sound from the two as the component types are pretty similar on both kits.
  Reply With Quote
Old 3rd February 2011, 12:54 PM   #3
AndrewT is offline AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
Do not use a 33+33Vac transformer with National's chipamps.
The highest voltage they are guaranteed for is 92Vdc(+-46Vdc) when no signal is present and 84Vdc (+-42Vdc) when signal is present.
A 35+35Vac transformer will typically give a "normal" voltage of 100Vdc (+-50Vdc) and worst case could be as high as 120Vdc (+-60Vdc).

It is usual to use ~25+25Vac for an 8ohm speaker and ~18+18Vac for a 4ohm speaker.
__________________
regards Andrew T.
  Reply With Quote
Old 3rd February 2011, 03:19 PM   #4
diyAudio Member
 
Join Date: Jul 2010
My bad ! Just was looking at the AFTER BRIDGE column on NUUK's
Power Supply help for Dummies . [ He has LM4870 , but I GUESS he
means LM4780 ! ]

Are there Circuit Boards or " Kits " available for the proper bridges
for a 60 Watt / Channel Chip Amp ?

My Hafler case is just 3" deep . Will either or both of the above two
kits fit in that depth ? If not , would " Low Profile " Caps be able
to be used on the supplied circuit boards?

David V. Webber
  Reply With Quote
Old 3rd February 2011, 07:58 PM   #5
diyAudio Member
 
ianpengelly's Avatar
 
Join Date: Oct 2006
I have the 3886 kits and if I recall correctly the caps with the chipamp kits are low profile, so would fit in a 1U case.

I'm not sure I understand your question about the proper bridges? Both kits mentioned come with full bridge rectifiers more than suitable for the task, in fact the ones that came with my kit are going to be driving 4 x 150W boards for a while whilst I figure out what I want to do.
  Reply With Quote
Old 3rd February 2011, 08:53 PM   #6
diyAudio Member
 
Join Date: Jul 2010
Default Wording :

I guess I should have said " correct " . Sufficient for the 60 Watts
per channel of the LM4780s . And , whatever , price - no - object
" Quality " .

P.S. :

Since this is the second 120 Hafler that died here , I now have
another unit for free . However , on the earlier oine , the XFMR was
good , and that is what the guy wanted . ( He did ask for all the
" guts " for the parts ) . On this one I know the XFMR is bad. But
the case could be used for a Chip Amp . Has massive Heatsinks,
all the normal plugs on the back , fuse and holder , lighted power
switch on front, the , ( damaged ), circuit boards and the MOSFETS
or whatever on the Heatsinks . Anyone who would like it need only
pay the shipping .

David V. Webber
  Reply With Quote
Old 3rd February 2011, 09:08 PM   #7
diyAudio Member
 
katana2112's Avatar
 
Join Date: Jan 2008
YGM
__________________
Aggressively Passive
  Reply With Quote
Old 4th February 2011, 02:02 AM   #8
diyAudio Member
 
Join Date: Jul 2010
What does YGM mean ? Also , I deleted the link of the guy who wanted the
" dead " Hafler . He was in California . I don't need money in advance ; just an address . I'll know what it costs to ship after it has been shipped . Then , he can send me that amount .
David V. Webber
  Reply With Quote
Old 4th February 2011, 02:34 AM   #9
diyAudio Member
 
Join Date: Jul 2010
Now the note from the second guy wanting the Hafler is gone ! Is there
a " Page Two " I am missing ??? David V. Webber
  Reply With Quote
Old 4th February 2011, 03:37 AM   #10
diyAudio Member
 
katana2112's Avatar
 
Join Date: Jan 2008
It means "You got mail"!
__________________
Aggressively Passive
  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


Similar Threads
Thread Thread Starter Forum Replies Last Post
LM4780 Kit and Transformer Selection bacworth Chip Amps 16 3rd June 2011 03:26 AM
new ChipAmp.com website - LM4780 kit and more BrianGT Chipamp 97 29th April 2008 04:29 AM
audio sector- lm4780 kit richyrich212t Chip Amps 1 25th August 2007 11:14 PM
bridging lm4780 kit joecool85 Chip Amps 1 23rd January 2006 07:26 AM
Question about Lm4780 kit G.L. Tirebiter Chip Amps 1 5th March 2005 01:43 PM


New To Site? Need Help?

All times are GMT. The time now is 10:01 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