Adcom 555II - Nelson Pass ? - Page 5 - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

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 11th November 2009, 11:14 PM   #41
diyAudio Member
 
Join Date: Apr 2007
they are 8 ohms KLF-30 Floorstanding Speaker - Specifications and thank you
__________________
Simplicity is elegance.
DIY=Sticken It To The Man
  Reply With Quote
Old 12th November 2009, 12:02 AM   #42
djk is offline djk
diyAudio Member
 
djk's Avatar
 
Join Date: Feb 2001
Location: USA
You posted here because you wanted an expert opinion, well you got one.
(former Klipsch and Adcom authorized service)

P.S.

Buy an ohm meter.
__________________
Candidates for the Darwin Award should not read this author.
  Reply With Quote
Old 12th November 2009, 12:04 AM   #43
diyAudio Member
 
Join Date: Apr 2007
i have a fluke 112 multimeter but it that is a inaccurate way of measuring because 8 or 4 ohms is a impedance not a resistance.
__________________
Simplicity is elegance.
DIY=Sticken It To The Man
  Reply With Quote
Old 12th November 2009, 02:27 AM   #44
djk is offline djk
diyAudio Member
 
djk's Avatar
 
Join Date: Feb 2001
Location: USA
In the region of the most output in most music, the impedance will only be a fraction of an ohm over the DC resistance of the speakers.

If you try and drive two pair of these '8 ohm' speakers you will blow up the driver transistors in the Adcom. Certain Infinity models would do it with only one pair.
__________________
Candidates for the Darwin Award should not read this author.
  Reply With Quote
Old 7th January 2010, 05:19 AM   #45
diyAudio Member
 
Join Date: Apr 2007
Quote:
Originally Posted by djk View Post
The Klipsch KLF-30 are 4 ohms, but the Adcom GFA555 will drive then just fine.

The Klipsch are not too hard to drive, despite their being 4 ohms (they are moderately efficient).
I just bought another gfa 555. My end result plan will be biamp for the KLF-30 speakers but in the meantime till i find a crossover can i bridge the amps into the speakers without any undue problems? Thank you for your insight btw DJK
__________________
Simplicity is elegance.
DIY=Sticken It To The Man
  Reply With Quote
Old 7th January 2010, 05:50 AM   #46
jleaman is offline jleaman  Belgium
Banned
 
Join Date: Apr 2002
Send a message via AIM to jleaman
Quote:
Originally Posted by Peter Daniel View Post
Must different amp then, because schematic shows 5 pairs.
Love it, i laughed so hard.!
  Reply With Quote
Old 7th January 2010, 02:14 PM   #47
docrw is offline docrw  United States
diyAudio Member
 
docrw's Avatar
 
Join Date: Feb 2009
Send a message via Yahoo to docrw
I had my terminals touch on the back of my 585, would someone help me find what needs to be replaced to fix that channel please.
David
  Reply With Quote
Old 24th March 2010, 04:22 AM   #48
anatech is offline anatech  Canada
diyAudio Moderator
 
anatech's Avatar
 
Join Date: Jun 2004
Location: Georgetown, On
Hi David,
Why all the yelling?

Anyway, I guess you didn't read the owners manual before messing around with the wires. Any chance of cut copper ends falling into the chassis?

You didn't mention what experience you have in electronic servicing, nor did you let us know what equipment you own or have access to. No way to assess your chances of success. Mind you, you don't sound like you have much experience from the looks of your post.

My first concern has to do with how you view what goes into a repair. There is far more going on than simply swapping parts, and that's if everything goes well.

Mechanically, you will need the proper thermal compound and an applicator. I like to use a #2 artists brush for this. You also need some fresh, clean mica insulators for each transistor and type. The mounting surface must be absolutely clean and free from dust. The new parts (or old ones) need to be snugged down evenly to approximately the correct torque.

Transistors, some should be matched for close gain. You must never mix old transistors with new ones, That is a critical point.

Did you take the time to read the other Adcom threads here? Almost everything you need to know will be contained in those threads. Don't go any further until you have read them.

One hint for you. Check the fuses in the holders across the rear panel. The lids accept a flat blade screwdriver, not a "Philips", or "star" screwdriver. If the blade isn't wide enough, you may wreck the cap. Be careful!

-Chris
__________________
"Just because you can, doesn't mean you should" my Wife
  Reply With Quote
Old 24th March 2010, 03:32 PM   #49
docrw is offline docrw  United States
diyAudio Member
 
docrw's Avatar
 
Join Date: Feb 2009
Send a message via Yahoo to docrw
No yelling just font size,,,, settle down.
I didn't touch them for fun! As you know amp designers think it's cool to put a pos and neg terminal right next to each other, I can promise you I'm NOT the first to have them touch because of this, but until they change it this will continue to happen. So to answer another question I am smart enough to check fuses and they don't always blow, I've seen this happen twice.

I've owned Adcom among many other brands for over 25 years, if that helps you know of my experience, but do not know a lot about electronics and have never worked on IC boards. I currently have a 585 blue boards, 750, 5500, 500, 555II, 555 of Adcom, and countless speakers many built by me.

I am somewhat interested in learning about doing some of this kind of work, (upgrading parts etc.) (I do not have leaky boards,,, yet) so this is what's driving my wanting to do a board upgrade but more over to fix the amp so I can use it for now.

You've given some good pointers Chris, but I'm going to need to find someone who's done one of these that could walk me thru it, I do have a PDF file sent to me by an Adcom person which discusses a revamp of a board with better caps etc. and it didn't look like it was to hard. He pretty much swapped parts (I can send you the PDF file, but it's to large for here) let me know.

I've searched the threads and haven't found anything useful, that's why I posted this and you're the only one who has really posted anything.

If I could find someone close I would have them do it, but haven't yet.

David
  Reply With Quote
Old 25th March 2010, 02:02 AM   #50
diyAudio Member
 
Join Date: May 2008
Hi Docrw,
I would suggest that you check out the following thread to get an idea what you are about to undertake when trying to repair this amp.

Another high DC Adcom GFA-555

Granted the above thread is for an Adcom GFA 555, not a 585, but there is A LOT of great troubleshooting information there. Also, understand that your 585 is a more complex amp (and more of a pain to work on) than the your 555.
  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
Adcom 5800 - Nelson Pass, others CLS2ASTAT Pass Labs 24 21st October 2012 10:21 PM
Adcom GFA-555II badfireguy Solid State 8 1st March 2012 06:02 AM
Adcom GFA-555II the apostate Solid State 32 2nd September 2011 09:41 AM
Dead Adcom GFA-555II K-amps Solid State 15 12th March 2007 07:06 PM
adcom gtp 500ll tuner problem, Nelson Pass maybe? crippledchicken Pass Labs 11 22nd January 2004 12:36 AM


New To Site? Need Help?

All times are GMT. The time now is 12:19 AM.


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