Converting Krell KSA 80B to KMA 160 - 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 14th November 2008, 07:39 PM   #1
NealW is offline NealW  South Africa
diyAudio Member
 
Join Date: Nov 2008
Default Converting Krell KSA 80B to KMA 160

Have got the opportunity to add another KSA 80B to my the one I already own but am only interested if I could convert it to a KMA 160 (to have a pair of monoblocks). I thought it wouldn't be a big deal and I have someone who has worked on my KSA 80B but he never did this conversion back in the day. The krell guys say it is difficult because there was a kit of parts that needed to be added. Has anyone done this and can they give us some guidence.

by the way i love this amp have been comparing it to a wyred 4 sound amp that is creating a buzz on the net and prefer the krell.
  Reply With Quote
Old 16th November 2008, 05:37 AM   #2
lineup is offline lineup  Sweden
diyAudio Member
 
lineup's Avatar
 
Join Date: Dec 2005
Location: the north
there should be some members that could advice you
I have seen several topics dealing with Krell amplifiers etc.
And been many done Krell 50/100 clones
__________________
lineup
  Reply With Quote
Old 17th November 2008, 02:01 PM   #3
NealW is offline NealW  South Africa
diyAudio Member
 
Join Date: Nov 2008
thanks yes in fact there is a thread on a conversion/ rebuild of a kma 160 back to ksa 80. of course i require the opposite and the amp is working fine so no other issues are at stake. of course i'm hoping some of the south african members reply then i may be able to contact them directly. as a newbee i'm not allowed to email members directly.
  Reply With Quote
Old 17th November 2008, 04:17 PM   #4
diyAudio Member
 
jacco vermeulen's Avatar
 
Join Date: Oct 2004
Location: At the sea front, Rotterdam or Curaçao
Send a message via Yahoo to jacco vermeulen
Quote:
Originally posted by NealW
no other issues are at stake.
No transformer swapping ?
__________________
No More Mr Nice Guy
  Reply With Quote
Old 18th November 2008, 02:50 PM   #5
NealW is offline NealW  South Africa
diyAudio Member
 
Join Date: Nov 2008
just mean the amp is in working order. are you saying the transformers need to come out in making the swap from ksa 80 to kma 160???
  Reply With Quote
Old 19th November 2008, 04:32 PM   #6
diyAudio Member
 
jacco vermeulen's Avatar
 
Join Date: Oct 2004
Location: At the sea front, Rotterdam or Curaçao
Send a message via Yahoo to jacco vermeulen
Measure the loaded voltage level on the rails of your 80B, multiplied by 2 if you put two secondaries in series is how much power ?
Secondaries in series still have the same current rating, but a power amp with twice the output power requires at least twice the current.
A conversion of a '90s stereo KSA-250 to a monaural MDA-500 required an exchange of the (very very large) transformer.
__________________
No More Mr Nice Guy
  Reply With Quote
Old 18th December 2008, 04:22 AM   #7
jwb is offline jwb  United States
diyAudio Member
 
jwb's Avatar
 
Join Date: Mar 2002
Location: San Francisco, USA
Send a message via AIM to jwb
You do not need to exchange the transformer to convert the KSA-80 to KMA-160. They are the same. You do, however, need to do some things.

1: You need to remove the input board on the left side (obviously).

2: There is a jumper wire on the protection board on the rear of the amplifier. It is dead center in the middle of the board, near the bottom, and about the size of a staple. Yours will be missing. You should install that jumper.

3: You need to fabricate a cable to carry the signal from the right rear driver to the left rear driver. This will have the same orange, brown, and gray wires that already connect the driver boards, but it will cross the amplifier from right to left, instead of running front to back. You can see this wire in my photo. It is the one that is disconnected on one side:

Click the image to open in full size.

4: After you do all that, you must adjust the pots on the top edge of the input board for bias level and DC offset! Very important!

Good luck!
  Reply With Quote
Old 18th December 2008, 04:26 AM   #8
jwb is offline jwb  United States
diyAudio Member
 
jwb's Avatar
 
Join Date: Mar 2002
Location: San Francisco, USA
Send a message via AIM to jwb
To make it more clear I have indicated the needed wire with orange arrows.

Click the image to open in full size.
  Reply With Quote
Old 10th February 2011, 01:40 AM   #9
diyAudio Member
 
Join Date: Feb 2011
Location: Hong Kong
Dear JWB

I am going to get a Krell KSA 80 in this weekend and planning to convert it into KMA 160 for my center speaker. Would you mind reposting the images again? By the way, I also need to add a XLR connector for true balance input for the amp, any suggestions for the parts?

Thanks in advance.

Regards
Jovi
Click the image to open in full size.
  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
Converting TO-220 to TO-247 Clipped Car Audio 5 24th July 2007 06:59 PM
Converting a DAC harrygrey382 Digital Source 48 15th June 2007 09:16 PM
Converting a DAC-in-the-Box to I-out? Aleksunder Digital Source 0 26th May 2007 11:44 AM
Converting a DCC into a DAC harrygrey382 Digital Source 0 21st May 2007 10:10 AM
Converting Bl ht_boy Multi-Way 2 12th December 2005 04:32 AM


New To Site? Need Help?

All times are GMT. The time now is 02:16 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