hi Eduard and Allen, thanks!
higher choke also means more voltage drop and with 20V AC secondary i'm already in tight spot. and in the interest of weight and size of the each mono amp chassis [which i'm yet to get] CRC should do for now.
now i need to power up the amp pcb! keeping my fingers crossed!
higher choke also means more voltage drop and with 20V AC secondary i'm already in tight spot. and in the interest of weight and size of the each mono amp chassis [which i'm yet to get] CRC should do for now.
now i need to power up the amp pcb! keeping my fingers crossed!
Hello,
The dcr of eachcoil of thelundahl choke is1,7 ohm so putting them in parallel will give you0,85 ohm. Voltage drop across 0,85 ohm will not be that big compared to a crc filter and it will sound way better. The original hiraga did have 24 volt power supply .
This is my last post her. Going to enjoy my holiday.
I am not a lundahl shareholder and I type one finger lol
Greetings, eduard
hehe! i appreciate your help Eduard . let me first power up my amp and later i might upgrade the PSU with those lundahl..
and enjoy your holidays!!
Ok. CRC can work. CLC is more difficult, it can give less ripple for the same voltage. Larger inductance doesn't mean more voltage drop but higher resistance in the winding does.
now that i'm done with updating power supply and soldering the amp pcb, i want to be careful when first powering up the amp board. i do not have access to a variac so i would have to do with direct power supply.
should i use a series light bulb tester without the soft start or just the soft is fine
-if both are combined then soft start doesn't trigger.
should i use a series light bulb tester without the soft start or just the soft is fine
-if both are combined then soft start doesn't trigger.
power ON your transformer + PSU via the Mains Bulb Tester (MBT).
Check that you have wired it up correctly and that it is giving out the correct open circuit (no load) voltages.
Do this BEFORE you connect any load.
Power OFF, add your load, then power ON via the MBT and again check you have the expected voltages.
if your soft start is delayed using an RC from a variable voltage then the RC delay can be so badly affected that it does not trigger, or repeatedly retriggers but never fully turning on the bypass. In this condition the soft start resistor could overheat and fail. This is one instance where using a Power Thermistor is at an advantage.
I regularly post that a proper "timer" be used to turn on the bypass relay. But this too can be affected if the voltage that passes through the soft start is severely reduced. i.e. if there is a fault in the wiring and the MBT wants to go to bright, then the timer circuit receives too low a voltage and can give false retriggering.
The MBT acts as a soft start, it is after all an added resistance in the primary circuit and thus the soft start can be omitted during the tests for incorrect wiring
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Dear cumbb, do you have a single psu schematics for a stereo 8W Le Monstre?
I would like to build an original Mr Hiraga design, but I do not have much electronics knowledge...
Can I replace original transistors by another Sanken ones? Wich are the most suitable if I cannot find the original ones?
Also, could be used film capacitors instead electrolytics in the amp PCBs? I can keep true class A design as close as possible from original project.
Thank you very much!
Nilton
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