Hi there,
I am completing parts for MX50 SE amp. PSU is the place I have most questions.
Transformer I have ordered will be 2x25V 250VA . Amp will drive 8ohms speakers. This power will be enought, even 25VAC after rectification will excees power and my listening volume needs.
Now my concerns regarding rectification. I don't want to wait for shipment of some kits from China but I see mostly two options in peoples projects.
8x2200uF such here
or 4x10000uF like here.
I am thinking about making two separate rectification boards , one for each secondary winding and MX50 module/channel. Now - will board with full bridge rectifier and 2x10000uF will be OK? Or better do it on 4x2200uF ?
I can purchase board like attached and I could arm this with two 20k uF caps.
I really wanted to understand how to calculate it, even simulate in PSUD2 software but sooner I will go crazy as simply I am not fluent in this matter yet.
It seems those values are simply that I can "go for" but I'd rather make sure and I like to understand.
Thank you
Jacek
Thank you
I am completing parts for MX50 SE amp. PSU is the place I have most questions.
Transformer I have ordered will be 2x25V 250VA . Amp will drive 8ohms speakers. This power will be enought, even 25VAC after rectification will excees power and my listening volume needs.
Now my concerns regarding rectification. I don't want to wait for shipment of some kits from China but I see mostly two options in peoples projects.
8x2200uF such here
or 4x10000uF like here.
I am thinking about making two separate rectification boards , one for each secondary winding and MX50 module/channel. Now - will board with full bridge rectifier and 2x10000uF will be OK? Or better do it on 4x2200uF ?
I can purchase board like attached and I could arm this with two 20k uF caps.
It seems those values are simply that I can "go for" but I'd rather make sure and I like to understand.
Thank you
Jacek
Thank you
> It seems those values are simply that I can "go for"
You don't quite know the circuit stray parasitics or the PSRR of the amplifier. IMHO these things are "designed by guess" based on experience. And there is no "right" answer.
For a single channel at 8 Ohms, one 1,000uFd is really cheap. It will sag, may buzz, but is good enough for unfussy users. Since many amps today use two caps, this will be two 2,000uFd as a sad minimum.
2,000uFd is good. This would be two 4,000u, or two 8,000uFd for stereo.
In the last 30 years such capacitor have become stupidly cheap, and big huge soup-cans of uFd excite some hi-fi fans. So two 68,000ufd, or eight 4,700uFd, or whatever you can find at bulk-discount pricing. Super-size rectifiers are also now cheap. So just fill the box.
You don't quite know the circuit stray parasitics or the PSRR of the amplifier. IMHO these things are "designed by guess" based on experience. And there is no "right" answer.
For a single channel at 8 Ohms, one 1,000uFd is really cheap. It will sag, may buzz, but is good enough for unfussy users. Since many amps today use two caps, this will be two 2,000uFd as a sad minimum.
2,000uFd is good. This would be two 4,000u, or two 8,000uFd for stereo.
In the last 30 years such capacitor have become stupidly cheap, and big huge soup-cans of uFd excite some hi-fi fans. So two 68,000ufd, or eight 4,700uFd, or whatever you can find at bulk-discount pricing. Super-size rectifiers are also now cheap. So just fill the box.