Krell KSA 50 PCB

hi everyone, how important is it that non inductive resistors are used for the output transistor emitters. Does anyone know where to get them from in the UK without it costing a fortune, the only type I have seen are thick film and they are about £3 each
Thanks, Alan
 
hi.I want to learn about krell ksa50's capacitors.. I saw 63volts 15000uf nippon kmh capacitors for 2,5dollars in a store.I thought paralleling them.But i always see big capacitors on projects.they are very expensive.I have some questions.

1)Which capacitor is more suitable for krell? paralleling little capacitors or using only two huge capacitors ?
2)Which brand capacitor is good for money to use in krell ksa50?

thank you very much
 
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Hello
I think that in orginal Krell capacitor is 40000uF
People say that is better 2X20000 rader that 40000uF but i dont yet build Krell clone and i dont know ( in Krell )

I have 4 x 33000 for the krell and a add 10000 for each capacitor ( 43000uf ) but my trafo is 2X32 400VA ( +/- 45V ) and i scare that this voltage is to much
 
Hi,
check the voltage rating of all the passive and active components.
Find out what the maximum DC voltage from your transformer is when on near zero loading and mains is at supplier's maximum tolerance.
Have you asked your electricity supplier what the tolerance is on your mains supply?
 
No I asked about any modification on the krell circuit. I have 600va 4x18 v ac toroidal transformer.I will connect in series and have 2x36 volts ac and use 6 pieces of nichicon kmh 63 volts 15000uf capacitors for getting +-50volts dc. Do you think there will be a problem? can i get only 10watts class a ? I will use 4ohms nokia german 185mm speakers.
 
I am in the process of building a Krell KSA 50. On the circuit boards I have obtained the value for C105 and C106 are 22pf, this also applies to the circuit diagram.

On all the other diagrams this value is higher at 390pf for C105 and C106. Which is correct? Does any body know?.
 
Update

I was checking settings on my amp before taking higher rail voltage (36 VDC loaded to 48 VDC loaded) and I've find some interesting things. Emitter resistors bias was only 298 mV / 0,5 ohm (drop from initial setting cca 320 mV) on warm amp (45 deg after 3 hours). So, I've raised bias to 340 mV (50 deg afer 3 hours) and...wonderful, deep and strong bass emerge. There was no need for offset adjustment becouse it was 0 mV and steady. I think that is the similar result with lower rail voltage / higher bias and higher rail voltage / lower bias (mk1 had 36,5 V rails and 1,9 A bias, mk2 had 48 V rails and only 1A bias). Statemants from Terry, pinkmouse, Jozua, PWatts, kvholio and my experience bring me to this conclusion.

Regards