Has any rewiring occured to your house?
Try a different outlet that shares another breaker. Maybe the breaker is going bad
Maybe the total load on the particular branch of outlets is near capacity with the considerable pull of the krell.
Are you using any kind of extension cord to power the amp?
Regards
David
Try a different outlet that shares another breaker. Maybe the breaker is going bad
Maybe the total load on the particular branch of outlets is near capacity with the considerable pull of the krell.
Are you using any kind of extension cord to power the amp?
Regards
David
Fingers crossed it's fixed this time.
If not then I think I would be contacting Krell direct to express concern over its products and its service organisation. Let's hope it's sorted
Keep us updated...
I've got some bad news for you sunshine .... good luck. It seems they don't give a rats a$$. I've complained (e-mail so I have a record) a few times about how difficult it is to program my Krell Showcase pre/pro, i.e. to make one change EVERYTHING, and I mean EVERYTHING, has to be re-programmed as you can't make a change without erasing everything back to the basic factory settings. I've asked for help, I've asked for updated software, and the only response I've received is send it in or they don't respond at all!! It's not rocket science to flash an e-prom.
I hope you have better luck but I wouldn't hold my breath.
It's been a long time since I visited this thread.
Frankly I had abandoned the project because I had too many things on my plate.
But I've gotten back into it. I have again replaced parts that got damaged last time. I've installed ceramic high powered resistors to replace the vitreous ones, and sleeved the leads and given them an inch of height off the board so they radiate their heat well away from other components.
Now the darned thing won't even start up! I suspect something has gone sour on the soft start board.
The schematic for the soft start board is BIZARRE. At this moment I can not explain how the diode across the power switch gets its ground.
Has anyone got a good clue of how that board works and cares to share some insights with me about it?
Or, better yet, does anyone have a good soft start board they want to sell to me?
I think the amp will run but for the (apparent) soft start problem.
Question for anyone who knows: Can I power up the soft start board if it's disconnected from each amp module? (Pull the black and white wires from the Phoenix connectors)
If I do that, do I also need to disconnect the red, yellow, and grey wires from the transformer to the amp modules as well?
My presumption is that the white and black wires are there for fault detection on the amp modules. Using a meter, these terminals read the same on both amp modules,
so I don't SEE any evident problem with the modules.
I'm now fairly certain that my big issue with the cap that blew up last time is that it was an old stock cap, too old even though it had never been used. I replaced all the caps of that type with brand new ones just last week.
Frankly I had abandoned the project because I had too many things on my plate.
But I've gotten back into it. I have again replaced parts that got damaged last time. I've installed ceramic high powered resistors to replace the vitreous ones, and sleeved the leads and given them an inch of height off the board so they radiate their heat well away from other components.
Now the darned thing won't even start up! I suspect something has gone sour on the soft start board.
The schematic for the soft start board is BIZARRE. At this moment I can not explain how the diode across the power switch gets its ground.
Has anyone got a good clue of how that board works and cares to share some insights with me about it?
Or, better yet, does anyone have a good soft start board they want to sell to me?
I think the amp will run but for the (apparent) soft start problem.
Question for anyone who knows: Can I power up the soft start board if it's disconnected from each amp module? (Pull the black and white wires from the Phoenix connectors)
If I do that, do I also need to disconnect the red, yellow, and grey wires from the transformer to the amp modules as well?
My presumption is that the white and black wires are there for fault detection on the amp modules. Using a meter, these terminals read the same on both amp modules,
so I don't SEE any evident problem with the modules.
I'm now fairly certain that my big issue with the cap that blew up last time is that it was an old stock cap, too old even though it had never been used. I replaced all the caps of that type with brand new ones just last week.
I purchased the Krell KSA 150 from High Performance Stereo in Florida. They replaced all the caps in the amp. It sounds amazing through my Acoustat 1+1s speakers and subwoofer system. It does run rather hot as any Class A amp design from this amp's original period in history. I measured the heat sink fins at 60°C
Pre-Amp: Classe SSP-600
Pre-Amp: Classe SSP-600
An externally hosted image should be here but it was not working when we last tested it.
I recently acquired a ksa 150. having removed the top cover I can see a couple of discoloured capacitors on the soft start board) the vertical one nearest the front that panel).
I'd like to replace the capacitors before they go pop and move the resistors out of the way as per described modification.
What is voltage to the large caps as I need to calculate resistor and power value to discharge them safely (my estimates is that a 240v 60w filament lightbulb will be fine).
Secondly what are the steps to remove the board?
What are the capacitor values on the s.s. board? Any brand preferred?
Also a photo of the repositioned resistors will be appreciated.
What Wattage are the current resistors and is there benefit fitting higher wattage?
Again info about the resistor type would be useful.
I'd like to replace the capacitors before they go pop and move the resistors out of the way as per described modification.
What is voltage to the large caps as I need to calculate resistor and power value to discharge them safely (my estimates is that a 240v 60w filament lightbulb will be fine).
Secondly what are the steps to remove the board?
What are the capacitor values on the s.s. board? Any brand preferred?
Also a photo of the repositioned resistors will be appreciated.
What Wattage are the current resistors and is there benefit fitting higher wattage?
Again info about the resistor type would be useful.
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I have a KSA-250. I moved the resistors to opposite side of board so they are close to front panel. They get hot.
To access board you have to remove front panel. You can see the bolts under edge of Fluke meter. There is an LED that protrudes into hole in front panel, careful with that.
I am not a tech so I cannot provide answers to other questions.
To access board you have to remove front panel. You can see the bolts under edge of Fluke meter. There is an LED that protrudes into hole in front panel, careful with that.
I am not a tech so I cannot provide answers to other questions.
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The construction is straightforward. Observe and you will see how to disassemble it. There are no special tricks to it. LOOK. It's not a hard amp to take apart or reassemble, but it does take time.
For component values and ratings, match to the originals. There is NO need to up-rate any capacitors to a higher value or voltage rating. In fact this can cause more problems than the problems it solves. (Which is none)
Do not replace power resistors with larger wattage ones as they are designed to act like fuses and protect circuits. Uprating them is like putting in a bigger fuse, which guarantees that a minor malfunction becomes a major flame-out instead.
For component values and ratings, match to the originals. There is NO need to up-rate any capacitors to a higher value or voltage rating. In fact this can cause more problems than the problems it solves. (Which is none)
Do not replace power resistors with larger wattage ones as they are designed to act like fuses and protect circuits. Uprating them is like putting in a bigger fuse, which guarantees that a minor malfunction becomes a major flame-out instead.
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