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FH9HVX - Budget Conscious 100w Class AB for Lean Times

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Joined 2013
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Can I ask what are the benefits of 2mm, 2oz and ENIG finish (versus 1.6, 1oz and HASL w lead) - which all add considerable fees to the PCB manufacturing. >15x the cost on JLCPCB?
Since the title is "budget conscious 100w class ab"? Wouldn't it make more sense to keep the PCB cost as low as possible?
 
Founder of XSA-Labs
Joined 2012
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The important one is 2oz copper for high current. The ENIG gives a nice looking board and 2mm makes it stronger but not critical. If we went 1.6mm, 2oz, HASL, I could offer for a bit less. How do you all feel about XRKaudio boards not being ENIG? That’s the normal finish level - needed for SMT work but that’s not the case here.
 
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Joined 2004
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The important one is 2oz copper for high current. The ENIG gives a nice looking board and 2mm makes it stronger but not critical. If we went 1.6mm, 2oz, HASL, I could offer for a bit less. How do you all feel about XRKaudio boards not being ENIG? That’s the normal finish level - needed for SMT work but that’s not the case here.

For the small difference in cost (guess less than $2) I’d prefer the usual XRKaudio standard of PCB.
 
Member
Joined 2013
Paid Member
The important one is 2oz copper for high current. The ENIG gives a nice looking board and 2mm makes it stronger but not critical. If we went 1.6mm, 2oz, HASL, I could offer for a bit less. How do you all feel about XRKaudio boards not being ENIG? That’s the normal finish level - needed for SMT work but that’s not the case here.

Offering 2oz copper, I agree is a needed upgrade.
Cost vs benefit - 2oz copper adds $16 to an order of 10, so very reasonable. But going to 2mm and ENIG adds +$50, which I don't think is worth it.
I have never snapped a PCB and they usually end up in a box no one can see inside.
 
Founder of XSA-Labs
Joined 2012
Paid Member
Hello xrk971
greetings its a very sweet sounding amplifier which i made on the driver
transistors i think 100pf caps where there have you omitted them or
are they not needed
warm regards
Andrew

Hi Andrew, I do recall you were one of the first to make the FH9. It is funny but my schematic for the orginal did not have the 100pF caps there, but Sonal K made the layout with them and so all the amps used have had them. Let me check with Hugh to see if they are necessary - I would hate to have JP change the layout this late in the game.
 
Founder of XSA-Labs
Joined 2012
Paid Member
Hi Folks,
Great to see the interest list growing! An easy to build, inexpensive, powerful, and great sounding amp. Good stuff!

Btw, JPS64 was kind enough to add some solder pads to add the optional 100pF caps to the drivers if needed. Vunce has tested the amp without the caps and it works fine. Under an OScope no oscillations. So it is there if we need it.

Thank you JPS64!!! You are so kind to help us, I’m sorry for imposing last minute changes like this on you. Please accept my apologies for this oversight.