[TomS]

Jim,

I built 2 complete stereo F4 amps, each one with two transformers and two full power supply boards inside.  Then I bridged them both as monoblocks as you suggest.  Just make sure your preamp has adequate voltage swing, about +/- 20 volts or so and they'll sing for joy.  The Aikido does this nicely though I am using a Bryston BP26 balanced to them right now because, well, it's just a really sweet piece. 

Good luck!

Tom

[poseidonsvoice]

If anybody else needs a pair of F4 PCB's, shoot me an e-mail. I have 2 pair and only need 1 pair for my projects. SOLD

Sorry no power pcb's, I have a ton of Peter Daniel's versions which are so flexible that I am using them in a multitude of other projects (you can use 4 pole caps or just regular caps. The 4 poles in contrast, make a difference in digital circuits while in analog ones like the F4 or F5 amplifier as TomS has stated is little if any...and they are UBER expensive).

Anand.

[jrebman]

The amp boards arrived yesterday and I also made contact with cviller on diyaudio and will be getting two of his PSU boards as well as diode boards when his container from Denmark arrives.

I also got a set of parts from jackinnj, so I'm well under way.

I'll have to go back to the building thread on diyaudio to refresh my memory about all the various tips and tricks, etc.  Also have to look up the ebay vendor for the nice heatsinks.  All that is a way off yet as I don't really have the money now to be buying the more expensive parts.

I also wanted to clarify that I'm building single board, single-ended monoblocks, not bridgeable.  25, or whatever it is, watts is going to be more than enough for the DX65 drivers, even with less than a 20v source.  I might even be able to go with 4 output devices per channel instead of 6, but that will just be part of the experimentation.

Thanks again to all who responded and offered boards and resources.

-- Jim
--

[jrebman]

Ok, so I'm a bit crazy... just read through that enormous thread on diyaudio and skimmed off the cream.  Got a lot of useful info, tips and tricks, etc., but there were a couple things that I could not find answers to, and again, they were probably covered in the pictures.

Anyway, if somebody could d3escribe to me the basic way the board, FETS, and heat sink goes together, I'd very much appreciate it.

I'm envisioning that the power FETs are probably lined up on each of the long sides of the boards and after soldering in position, are bent parallel to the board and the devices bolted to the heatsinks (following normal insulating practices, etc.).

Assuming that is correct, and that the rest of the components mount on the side of the board away from the heatsink, where on the heatsink is this whole assembly placed?

Or have I just got this totally wrong?

So, that's pretty much what I'm trying to figure out -- the rest of the layout, PSU, trafo, I/O, etc. will all fall into place, and will probably also be easier given that I'm building single-ended monoblocks and there will be one heatsink per monoblock.  Again, assuming that all devices for one channel mount on the same heatsink and that I haven't made any other wrong assumptions.

Thanks,

Jim

[TomS]

Jim,

Peter Daniel designs all of his boards with the same Mosfet spacing.  In the case of the F4 there are three on each side of the board.  You are correct that for a flat heat sink the output devices would be parallel to the sink (in the same plane).  I just mounted mine in the very center of the Conrads in a horizontal fashion.  This put 3 of the devices about 1/3 from the front of the sink and the other 3 about 1/3 from the rear.  The boards are so light that with six devices you don't really need standoffs this way either.

Hope this helps.

Tom

[jrebman]

Tom,

Yes, helps a lot and confirms my mental image of how it all goes together.

I think these are going to be a real treat with the Alerions.

-- Jim