In pursuit of Ultra-LOW-THD many people forgot about multi-tone IMD (IMD's noise).
I can think of winding 1 meter of 18SWG enameled wire over iron power toroidal core suitable for DC-10MHz and of size from T68-26 to T90-26 etc. Will that work as L?
I usually buy my inductor, a value around 2mH normally does the trick. IIRC this value has also been used on some of Nelson Pass power supply. 30000uF - 2mH - 30000uF for the + rail and the same for the - rail using 2 bridge rectifier.
This is what I will use when I get started with this project.
Rgds,
Eric
This is what I will use when I get started with this project.
Rgds,
Eric
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An inductor with decent Henries and capable of passing 2A continuous current is a hard to find component. Most inductors are either for RF or for valve amps with current ratings of less than 0.5A.
Shoog
Most power supply filter chokes are intended for tube gear - eg 8H @ 100mA
We need multiple amps but at lower H - most tenth-of-a-H inductors are designed for speakers and can't stand any DC
I agree for the Pass Amp Power supply.
But in class D or class T amplifier which has high current as well as switching frequency 250KHz-1200KHz, output LC LP filter with just L=33 µH, C=0.68µF can smooth anything beyond 33KHz. So why not here?
IMO 2mH is bigger value. little 100uH-500uH should do the job.
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These are designed specificaly for DC.
Hammond Mfg. - D.C. Filter Chokes - (153 - 159 Series)
Rgds,
Eric
The Hammond range is very limited in Europe, which means big postal costs to bring from Canada.
I stand by my statement, high current inductors are not easy to get in most places.
Shoog
I stand by my statement, high current inductors are not easy to get in most places.
Shoog
I find similar problems sourcing specialised components in my country.
Usually the postage is more than the price of the component,
Then my country's customs adds 20% plus import cost to that price.
🙁
Usually the postage is more than the price of the component,
Then my country's customs adds 20% plus import cost to that price.
🙁
Thick wire XO coil can be great to! Just pick 16AWg or thicker wire . air core of course.
You can wind your own if you got magnet wire.
Greetings
You can wind your own if you got magnet wire.
Greetings
I think for the Monster these would work well
https://www.solen.ca/pub/index.php?...eau1=1&niveau2=4&niveau3=70&s1=2&s2=4&s3=&s4=
Solen electronics has up to 10AWG coils just way to expensive because the copper price.
I saw people used metal core inductors to.
If you can get second hand or wind yours that would much be cheaper.
The bigger the size of the coil is better.
Hard to say how many wind, wire thickness, coil size all ad up.
Greetings
https://www.solen.ca/pub/index.php?...eau1=1&niveau2=4&niveau3=70&s1=2&s2=4&s3=&s4=
Solen electronics has up to 10AWG coils just way to expensive because the copper price.
I saw people used metal core inductors to.
If you can get second hand or wind yours that would much be cheaper.
The bigger the size of the coil is better.
Hard to say how many wind, wire thickness, coil size all ad up.
Greetings
Received the Jim's audio kits today.
each kit contains:
-- two Muse 47uf/50v electrolytic cap. Looks like the KZ series.
-- one 100 ohm trim-pot.
-- Four 2.2R resistors (parallel to make two 1.1 ohms I supposed)
-- one 250R resistor (feedback).
-- one 10R resistor.
-- one 1k resistor.
-- one 47k resistor.
-- four 2.2k resistor.
-- two 390R resistor.
-- PCB
-- 2SJ74/2SK170, BL grade.
-- A872/C1775
-- D716/D756
-- NJW0281G/0302G
Everything was in a clear poly bag (the FET pair wrapped in aluminum foil though).
So the FET's are BL grade. The original design used Y grade. Other than the different IDSS (which required changing resistor value from 1k to 390R, I suppose), what is the difference between different grades? Any perceivable difference in sound?
And if I like the Monstre and want to gather parts myself, what are the critical transistors that must remain the same? I suppose the FET's should stay the same models (otherwise everybody would have been using the replacement FET's by now), what else?
each kit contains:
-- two Muse 47uf/50v electrolytic cap. Looks like the KZ series.
-- one 100 ohm trim-pot.
-- Four 2.2R resistors (parallel to make two 1.1 ohms I supposed)
-- one 250R resistor (feedback).
-- one 10R resistor.
-- one 1k resistor.
-- one 47k resistor.
-- four 2.2k resistor.
-- two 390R resistor.
-- PCB
-- 2SJ74/2SK170, BL grade.
-- A872/C1775
-- D716/D756
-- NJW0281G/0302G
Everything was in a clear poly bag (the FET pair wrapped in aluminum foil though).
So the FET's are BL grade. The original design used Y grade. Other than the different IDSS (which required changing resistor value from 1k to 390R, I suppose), what is the difference between different grades? Any perceivable difference in sound?
And if I like the Monstre and want to gather parts myself, what are the critical transistors that must remain the same? I suppose the FET's should stay the same models (otherwise everybody would have been using the replacement FET's by now), what else?
