No. Notice the rail will not clear the top of the cap so it won't bolt to the main board. It has to be lined up perfectly to operate.
The only option I can think of is to go down in capacitance and maybe find a cap that will fit. The original schematic has 13,000uf/63V for the main filters; maybe a lower value will filter properly. I will probably call Krell Monday.
The only option I can think of is to go down in capacitance and maybe find a cap that will fit. The original schematic has 13,000uf/63V for the main filters; maybe a lower value will filter properly. I will probably call Krell Monday.
They are good ecaps. I could not get those from RS / Mouser here.
It may be difficult to put them in. I have done cutting the stud and the legs of many caps before at other restoration projects.
1. Measure the H height allow at the amplifier's rectifiers PCB.
2. Measure the new 33,000uF caps of the H' you can achieve after cutting the stud and the (+) and (-) legs
3. If H' is still longer than H. DO NOT DO the action and try to buy a lower caps (e.g. 27,000uF 63V E32D630HPN273MC79M 80mm height)
4. Place big hole metal washers to allow cutting a leveled surface of the cap leg as well as protecting the below.
*** please evaluate if you have the skill to do that before you start***
If you can change the caps and tune up the bias, you have the good sound and unique KST-100.
It may be difficult to put them in. I have done cutting the stud and the legs of many caps before at other restoration projects.
1. Measure the H height allow at the amplifier's rectifiers PCB.
2. Measure the new 33,000uF caps of the H' you can achieve after cutting the stud and the (+) and (-) legs
3. If H' is still longer than H. DO NOT DO the action and try to buy a lower caps (e.g. 27,000uF 63V E32D630HPN273MC79M 80mm height)
4. Place big hole metal washers to allow cutting a leveled surface of the cap leg as well as protecting the below.
*** please evaluate if you have the skill to do that before you start***
If you can change the caps and tune up the bias, you have the good sound and unique KST-100.
Attachments
Well, I'm throwing in the towel on trying to get these taller caps to work. Krell sure didn't make it easy to change the filter caps on this amp!
Etsang3, thanks much for the details on trying to make these work. I was just about to cut one of the caps when I saw the 4ea .1/100V caps that are mounted to the bottom side of the main board. Well the one's in the back fall up under 2 of the filters! Crap. I don't think there is room to move them to the other side and I don't want to replace and fold over.
I'll just stay with the 30yr old filters and hope they hang in until I can find another solution.
Etsang3, thanks much for the details on trying to make these work. I was just about to cut one of the caps when I saw the 4ea .1/100V caps that are mounted to the bottom side of the main board. Well the one's in the back fall up under 2 of the filters! Crap. I don't think there is room to move them to the other side and I don't want to replace and fold over.
I'll just stay with the 30yr old filters and hope they hang in until I can find another solution.
As an update and for others, Krell recommended that I NOT change the main filters unless they have cracked and malfunctioned. Their tech support had confidence that they generally last a long time and don't go bad. I changed the small electrolytics, cleaned everything up and set the bias to 80mV. I'm auditioning as I speak and sounds good so far and no excess heat! Thanks for the help on this one.
Well.....a few more things happened since I posted last. This KST100 ran really well in stereo, but I had another KST that I've owned for several years and the reason I added another was to run mono blocks. Anyway, after I had recapped the amp (I left the big filters alone), the amp would not go into mono, it would trip the protection. I finally bit the bullet and sent it to Krell for repair. The issue was the toggle switch Krell used for "stereo/mono" switching. They are not reliable. This amp also required new relays; the big filter caps were tested and deemed good.
I have to give a big thumbs up to Krell! They really are a pleasure to deal with and really want customers to feel good about owning "legacy" products. Krell was kind enough to send me a jumper set to change out the toggle switch in my other KST and I have done that as a preliminary precaution. Just an FYI, I checked the repaired Krell's bias from the factory and it was set @ 86mV. I then adjusted my other amp to the same and I'm running mono currently. Very big slam; imaging improved; very pleased.
Now on to recapping my vintage KEF 105.2 with recap kit from Falcon UK.
I have to give a big thumbs up to Krell! They really are a pleasure to deal with and really want customers to feel good about owning "legacy" products. Krell was kind enough to send me a jumper set to change out the toggle switch in my other KST and I have done that as a preliminary precaution. Just an FYI, I checked the repaired Krell's bias from the factory and it was set @ 86mV. I then adjusted my other amp to the same and I'm running mono currently. Very big slam; imaging improved; very pleased.
Now on to recapping my vintage KEF 105.2 with recap kit from Falcon UK.
Last edited:
I just got one of those KST-100 amplifiers on my workbench. This has the bias set to just 86mA. But I have a problem with it, it quite often blows the wall fuse when I power it on. This is due to the current inrush, is this a common problem?
It got much better when changing the voltage setting from 220V to 240V since we have nominal 230V in Sweden, and where I live always 240V.
It got much better when changing the voltage setting from 220V to 240V since we have nominal 230V in Sweden, and where I live always 240V.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.