I currently am using a KSL with KSL phono that I recapped. Short story, my diy DAC has discrete balanced output that sounds a little better than SE out so I wanted a balanced pre. I didn't pay that much for it so I wasn't worried about sending it to Krell for an OEM re-cap to keep the resale value high. A fellow owed me a favor and supplied me with United Chemi-Con caps for it.
The KSL isn't that highly regarded by some. IMO it is a warm sounding SS pre. Now the KRC HR is rated much better...and costs a bunch more. I had one on loan for a while. I could run the KSL with Sanders AB amp, but the KRC HR with Sanders amp seemed too detailed and fatiguing. The HR sounded great with the KSA 250 though.
I have no idea about biasing. I did have to fiddle with one pot on the phono boards left channel to match the right channel bias and zero out the left channel dc with another pot.
My KSA-250 started to crackle on the left channel. A Krell tech told me to tap on the output relay. Crackle gone. I pushed and tapped on the left channel boards with my wicked stick and couldn't make it crackle again so hopefully its just the output relay for that output. I'll have to try swapping the speaker cable to other output next time I start it up and have crackle issues since each output has its own relay.
So I was looking at the soft start board. I thought I had a version 3 KSA-250 since it ran cooler than the other KSA-250 I had. The binding posts on both the KSA-250's I have owned were/are horizontal. But the soft start on my amp appears to be the same as the version 1 (vertical binding posts) amps I have seen internal pics of. Unfortunately I don't have pics of the soft start board on the previous amp I had.
At any rate, there is plenty of room between front panel and board to move the 700 Ohm resistors to the opposite side so they don't cook the caps. Any objections to the side swap?
So I was looking at the soft start board. I thought I had a version 3 KSA-250 since it ran cooler than the other KSA-250 I had. The binding posts on both the KSA-250's I have owned were/are horizontal. But the soft start on my amp appears to be the same as the version 1 (vertical binding posts) amps I have seen internal pics of. Unfortunately I don't have pics of the soft start board on the previous amp I had.
At any rate, there is plenty of room between front panel and board to move the 700 Ohm resistors to the opposite side so they don't cook the caps. Any objections to the side swap?
Wow, cannot believe that was a whole year and a half ago... I sold the KSA250 and KSL preamp a while ago, as the KSA-50 clone I built sounded quite a bit better, and it was all class A (no sliding bias). And since class A, it gets toasty HOT. Not exactly same power wise (my clone biased to 72 wpc @ 4ohms) but I am not driving Apogee Scintillas (well, not yet)
The KSL preamp was nothing special. Never had the KRC-HR. Preferred my Aikido Tube Pre more. The KSL seemed needlessly complicated, circuit-wise, too.
Ask any Krell Tech - which amp was the best sounding Krell amp for the money - I am quite sure he would say the KSA-200. No sliding bias, nothing but raw power and HEAT!
The KSL preamp was nothing special. Never had the KRC-HR. Preferred my Aikido Tube Pre more. The KSL seemed needlessly complicated, circuit-wise, too.
Ask any Krell Tech - which amp was the best sounding Krell amp for the money - I am quite sure he would say the KSA-200. No sliding bias, nothing but raw power and HEAT!
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Hi John! Time flies! I sold the KRC-HR I had picked up. An Audio Research Reference 3 took its place. Still happy with the KSA-250.
I built a Bottlehead Eros tube phono pre to replace the Krell Reference MC phono board. I use a Park's Audio Budgie SUT to step up my LOMC cartridge. I like it much better. After I swapped the Ref 3 in a friend said you're not gonna take that back out, are you?....
I made a custom crotch walnut base for my Eros. Next up a new matching walnut plinth for my Lenco turntable.
I built a Bottlehead Eros tube phono pre to replace the Krell Reference MC phono board. I use a Park's Audio Budgie SUT to step up my LOMC cartridge. I like it much better. After I swapped the Ref 3 in a friend said you're not gonna take that back out, are you?....
I made a custom crotch walnut base for my Eros. Next up a new matching walnut plinth for my Lenco turntable.
I moved the two 700 ohm soft start resistors to other side of board. Plenty of room between front panel and board. They get really hot, over 400F.
I recapped the start up board and also moved my resistors when I had my KSA-250 amp.
Yes I built a Bottlehead Foreplay preamp years ago - they were only $100 for the kit, now they re many times more expensive!! Shocked?
I also have a budgie phono circuitboard, but currently use a modded Little Bear tube phono. Not bad...
Yes I built a Bottlehead Foreplay preamp years ago - they were only $100 for the kit, now they re many times more expensive!! Shocked?
I also have a budgie phono circuitboard, but currently use a modded Little Bear tube phono. Not bad...
I rebuilt a KSA 200 a few moons ago. I doubled the wattage on the softstart resistors and they were much happier for it.
I am making a list of caps needed to order for my version 2 KSA-250, but cannot see the value of one that is buried between the boards sandwich.
It is located on the driver board towards the rear. It looks smaller in physical size than the other radial caps populating the board so I figured the value might be different than the rest. I circled the cap, wondering if someone can can provide the correct value.
Thanks!
It is located on the driver board towards the rear. It looks smaller in physical size than the other radial caps populating the board so I figured the value might be different than the rest. I circled the cap, wondering if someone can can provide the correct value.
Thanks!
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