F5 power amplifier

sell your car

buy a house with big living room

make big spks

make just two channel F5

it will roooooom!

or - think about best way of having at least +/-15V as power supply for amp(s) ...... in car

that's twice 15V ..... conveniently connected

:cheers:

for home work :

what's difference between AC and DC

for which current xformers are effective and intended

Thanks. I changed transformer to voltage multiplier.

I could make a virtual CT to get the split rails, but I'm not sure the components generally used could handle the current.

But maybe that's why the chip amps are so popular in car audio now. :gasp:
 
I think he meant current Class AB and good Class D.

So did i.
Anything but Class D for a subwoofer is nuts, but Class AB amps in cars still sound better, preferably high bias.
Car acoustics always suck though, i have a back window open when i drive alone, summer and winter.

The joy of having neighbors who love to compete with the latest posh car models is a 365 day car show up your alley.
No30 drove a Continental GT before, got the Porsche 4-seater months before the official sale date overhere.
Burmester Panamera surround system, AB amps + Class D for the sub (excuse my fatness)=>
 

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after a year and half and numerous interruptions with other DIY projects, i finally finished my F5. it's basically "stock" with 132,000uF in the remote PS and another 44,000uF in the amp proper. biasing at 1.3A with 0V DC offset was simple enough too.

i don't need to wax about how great this amp is - everyone that has built one knows. my B1/F5 combo is driving a pair of uFonken^2, with a pair of Fostex FF85K per side. it also drives my AKG K702 headphones beautifully as well.

a huge thanks to Nelson Pass for making this project possible and for sharing his passion and knowledge for the benefit of the DIY community :cheers:.

here's some pics: http://www.diyaudio.com/forums/pass-labs/166784-pictures-your-diy-pass-amplifier-36.html#post2332027
 
Funny you ask about them. I ordered some Mica T0-247 insulators from Hong Kong last night and he had those rectifiers also. I figured what the hell, they are $1.88 so I got 2 to try.

Be few weeks before they come, but we shall see.

Here is the spec sheet on them. They are from SEP electronics.

Chad
 

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Power supply question. So I'm in the planning process for a balanced F5's (mono blocks). I have (4) of cviller's boards and I'm wanting to populate the second pair of output FETs to allow for trying higher bias's. I'm looking to "beef up" the power supply by maybe using a single P/S board (standard layout per Nelson's schematic) to run each F5 board (overkill?).

Do you guys see any potential issues with the FX5 layout and doing something like this?
 
Power supply question. So I'm in the planning process for a balanced F5's (mono blocks). I have (4) of cviller's boards and I'm wanting to populate the second pair of output FETs to allow for trying higher bias's. I'm looking to "beef up" the power supply by maybe using a single P/S board (standard layout per Nelson's schematic) to run each F5 board (overkill?).

Do you guys see any potential issues with the FX5 layout and doing something like this?

An Xed amplifier benefits to be supplied commonly.(one PSU only)

To deliver the full power into 8 ohm class A, you need to bias each board at 2.6A. Because a bridged amplifier sees half the real load. That means four times the dissipation compared to a regular F5 channel.

The psu (transformer and capacitance) has to follow this requirement.

Or lower the rails voltage. Or accept to leave class A at medium power.
 
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I was planning to use a 750 -1000 VA transformer per mono-block. From some of the reading I did in this thread, it sounds like people recommend at least 60,000nF per rail for the standard stereo setup.

If I wanted to run dual output devices at the standard 1.3A bias, seems like you would simply double the capacitance in the power supply (more/larger capacitors).