PCB routing for audioamps

[JensRasmussen]

Originally posted by Yoghourt
Fifth, I sleep on it, then slap my face because I realize I've missed something, and rework the lot

Been there to often

\Jens

[mikeks]

Originally posted by jacco vermeulen


Mike,

you think that is always superior to a 1-board solution ?

Not always convenient......the same principal can be implemented on a single pcb....e.g: by keeping each module away from the other..

[sam9]

In a similar thread someone wrote that for amps they put the output section on one PCB which is mounted parrallel to the heatsink and the IS and VAS sections are on another boad that plugs into the output board at 90 deg. This keeps the signal fairly short, the small signal sections stay a little cooler and the 90 deg angle reduces undesired interactions.

[jacco vermeulen]

Sounds like computer building: motherboard and plug-in boards.
Makes amp building more compact, like the Halcro shows.

Not meant ironically, Mark Levinson had a modular amplifier once, with special sota connectors.
That would make repairs a breeze.

Maybe time for a Rubick amplifier, pcb's in all planes.

[mikeks]

Originally posted by sam9
In a similar thread someone wrote that for amps they put the output section on one PCB which is mounted parrallel to the heatsink and the IS and VAS sections are on another boad that plugs into the output board at 90 deg. This keeps the signal fairly short, the small signal sections stay a little cooler and the 90 deg angle reduces undesired interactions.

Good idea...but the connections would stillhave to be soldered in for secure connection...particularly the feedback loop!

[JensRasmussen]

Originally posted by mikeks


Good idea...but the connections would stillhave to be soldered in for secure connection...particularly the feedback loop!

YES!

\Jens

[mikeks]

Originally posted by jacco vermeulen
Sounds like computer building: motherboard and plug-in boards.
Makes amp building more compact, like the Halcro shows.

Not meant ironically, Mark Levinson had a modular amplifier once, with special sota connectors.
That would make repairs a breeze.

Maybe time for a Rubick amplifier, pcb's in all planes.

May decide to market an amp. consisting of a base in which gain cells of different designs can be purchased and merely plugged in.....

Excellent for subjectivists methinks...

What d'yall think?

[sam9]

May decide to market an amp. consisting of a base in which gain cells of different designs can be purchased and merely plugged in.....

The app notes on the LT1116 (Mosfet auto bias) IC have an example that looks like that. An opamp input section on a mother board then plug in the modules 100W at a time. Obviously the app note is intended to peddle LT products, and I seem to recall the liosted specs didn't seem spectactular, but maybe there's a useful idea in there somewhere.

[mikeks]

Originally posted by jacco vermeulen

(did anyone ask who the goodlooking on Mike's avitar is yet? )

'Delectable' is her middlename...

[i]A legend is dead: John Zachary DeLorean.
Oh, the Pope too,i gather, but he had other designs![/B]

True! The last sentence that is...

[lumanauw]

Hi, Sam9,

I experienced what you described. Due to space limitation, I have input RCA and speaker output terminal at the same side of PCB, and the result is that the channel that is closest to the RCA input is oscilating, while the other channel (far from input RCA) is not oscilating. Both has exactly the same schematic.

Is there any way to fix this problem without redrawing the PCB?

How does the output trace influence the input trace? Is it via the fiber-glass material of the PCB or via air (inductance-radiation)?

If it is via fiber-glass material of the PCB, maybe I can put ground track between input and output tracks, but if it is ramping via inductance-radiation(air), this ground middle track won't help?