RMI-FC100, a single stage audio power amplifier

[Jay]

Me built loudspeakers.

I really want to see it 😉

So we pay attention to the useless micro detail in an amp implementation. But look at the baffle where "we" put the tweeter on. Aren't we so HOPELESSLY forgiving?? 😀

 

[jacco vermeulen]

Jay,

sorry to dissapoint you, no baffles and no tweeters.

 

[Jay]

Jay,
sorry to dissapoint you, no baffles and no tweeters.

Waaaa.... I knew it! Your wall full of strings? 😀

 

[jacco vermeulen]

electrostatics

 

[Luke]

Luke,

what's in a board(walk), if the parts are the real investment.
Another Class Éeh design board set for an example, in sizes not likely to experience with GB endeavours (yet), but requires 6 matched J109/K389 pairs for starters. (also balanced in, balanced out, relay switched)
All things relative, the mark-3 retails for $30K on the Euro continent : Classe Omega Pre-amplifier MkIII - Preamplificatori Stereo Serie Omega
Me kick everything, except tyres.

The tricky part of the ExtremA is the cooling for output power levels above 50W/8 (for 100W, the dissipation number goes up to ~260W, coming out of 4 power devices)
The design has turned a Dutch thing mainly, to some extent because the ExtremA mag article has only been published in the Cheese edition.
Not overwhelming builder response in NL either, nine of ten audio DIY's lack project mileage (/age).

R-cores are grand, if easily obtained, otherwise use an EI instead of a toroidal (cheaper and superior).
Best EI is one with separate winding sections (split bobbin type)

Hi Jacco,

boards are difficult to make and reasonably costly. I would build an Omega 3 if I had a the boards, if you gave me a schematic I wouldnt bother. I may take the analog linestage and breadboard it if its simple, but probably not. So are the Omega 3 boards available to diyers or is it a special deal?

I didnt realise the ExtremA is 260 watts of heat. I thought it would be 50watts class A and then push pull. I Should read the article.
I am jsut about to finisha couple of projects that have been lingering, so its the Leach or maybe something abit more exotic. The ExtremA sure has a sexy look about it, and I can deal with that much heat on one sink.

 

[loek]

electrostatics

Hi Jacco, nice to see the result of the pool cover.
I would not use electrostatics either in the pool....
Loek

 

[Luke]

Hi Jacco, nice to see the result of the pool cover.
I would not use electrostatics either in the pool....
Loek

keep the toaster away from the pool too, as tempting as it may be🙂

 

[jacco vermeulen]

or is it ?

Still current production makes it a special deal.
B&W may likely place it at the combined service site for their brands, once the preamp turns obsolete.
Let's not upset Jay any further with more thread off-topic talk.

(Loek, 30C inside, less than 0.5C temp droop-drop overnight, not bad. Remember, zwembroekie on the next Maaskantje visit)

 

[Luke]

yes agreed, but there's not alot of "on-topic" talk here at the moment.

 

[AndrewT]

If a toaster is thrown/dropped into a swimming pool, will that have any effect on life in the pool?

 

[Zen Mod]

not on that sort of (Whale) life

 

[jacco vermeulen]

there's not alot

You're free to email me for schematics of a preamp half as complex, without active IP issues, may give you an indication if it's in/out of your league. Something like Francois' UGS preamp makes life much easier, see example pics (rear Cl. board top, UGS main board bottom).

 

[AndriyOL]

Completely off-topic. You can create a separate thread. This thread is already big enough.
Regards.

 

[jacco vermeulen]

no need, i don't even need to talk to you.

 

[koldby]

A little off topic, but can anybody tell me where I can find the component placement for the front end PSU? (I have the PCBs and I am building right now)
__________

 

[loek]

Koldby, i have made a rough drawing, will scan it if you want it.
Loek

 

[koldby]

I would appreciate that very much - Thanks

 

[loek]

drawing PSU

This it what i also found, you have to make some wire connections also(blue in pdf).
Good luck, Loek

 

[koldby]

Hi loek
Just what I needed . Thank you very much.
Did you make the amp?
Are you content with it?

 

[AndriyOL]

Koldby, how is a blue ground trace from C16 to TP4 made in you PCB?
In layout it's goes directly through C14 capacitor shorting it.