I recently changed speakers to a 2.5 way, where 3 Accutons C173 drivers run in parallel in lower bass area. Impedance minimum slightly lower than 4 ohm, efficiency 89dB. Not being my main topic, the speakers are great.
J2 (diy attempt) is even more great, but can not deliver the volts/amperes in the bass section for my speakers.
I have the idea to build a Turbo-J2 - if that makes sense at all - but I am not an amp-circuit designer expert.
Thinking about parallel Semisouth in output.
Any idea's / suggestions on a J2-like 'simplified' schematic with parallel Semithsouth in output ?
I recommended ACA because after building F6, the ACA looks interesting with SS fets because it has no degeneration on the lower fet. So if you haveheard the ACA and like the sound with IRF's, the SS in lower position becomes even more interesting.
Nelson,
Is the feedback in the ACA acting as a two stage schade circuit?
Nelson,
Is the feedback in the ACA acting as a two stage schade circuit?
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Perhaps. The biggest issue is deciding on what will be the specified input transformer(s). (As specifying one may be inconvenient for some)I would also like to take a peek at the production version's schematic to see what everything evolved into...
That said, the Tea-Bag PCB kinda sorta fit on the UMS.
That said, the Tea-Bag PCB kinda sorta fit on the UMS.
The single biggest issue is magnetic induction - those tiny little transformers are in the same metal case as a big-honkin' toroid, which even if shielded, has magnetic flux all around. So in a perfect world, the input transformers are both on the same side of the case, and as far from the power transformer as possible - this means, most likely, a mirror set of PCB.
Now you could of course mount one 'upside down' in regards to the other, but then the output devices will be mounted low on one channel's heatsink, and high on the other. This will have effectively no difference on the heat transfer and efficiency of the heatsink, but trust me, the natives will become very restless and much gnashing of teeth will occur. They hate things that are unsymmetrical...
Anyway, more space between 2 mosfets isn't the issue for this amp, transformer mounting position is everything.
Now you could of course mount one 'upside down' in regards to the other, but then the output devices will be mounted low on one channel's heatsink, and high on the other. This will have effectively no difference on the heat transfer and efficiency of the heatsink, but trust me, the natives will become very restless and much gnashing of teeth will occur. They hate things that are unsymmetrical...
Anyway, more space between 2 mosfets isn't the issue for this amp, transformer mounting position is everything.