"WHAMMY" Pass DIY headphone amp guide

So I finished my build on this amp last night. And although my PSU passed with flying colors earlier, I’m not getting D5 until the headphone jack is fully engaged or the power is turned off. Also there is no sound until power down and then it’s horribly distorted. Does this raise any red flags? Maybe a quick, “Oh yeah, you did this...”? Will provide any info necessary, just ask.
 
The higher voltage one sounds like bad mosfet or open source resistors.

I had measured each resistor and they were good. So not that. I replaced the mosfets. So I hope they were good. Though the amount of rework made me wonder. I redid the regulators and mosfet connections.

I hear good sound. :) This time on both channels.

Glad I tried this before trying to replace 4N35.

Sincere thanks to everyone for the help. :worship:

I have a spare, unused 4N35 if anyone wants it at 80501.
 
Perhaps a tad bright :)

Grado SR60 sounds fantastic.
 

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Awesome Sound

Thanks Wayne,
The sound is great. I am not 100% finished yet. Still working on the VU meters and power lights hook ups.
 

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Switches things on and off again
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Thank you Wayne for this great project!

We now have a very small number of WHAMMY parts kits listed in the store, available with or without the PCB for those who may have already bought a PCB.

Once we have feedback about completed builds, I'd guess a few weeks, we'll make more available for sale. Please only purchase one if you are planning on making it soon and can give feedback, otherwise you might as well wait until we give the official unreserved green light of approval. There will not be a long wait for the rest to become available for sale.

There is currently no official chassis, we are going to take our time on that, but there will be one eventually (no doubt using a Hifi2000 chassis).
 
I'd definitely be interested in a nice custom chassis. Not wanting giant or full custom prices has kept me from straying from cheap options in my planning.

But in the meantime, any chance of a BOM for the kit? I've been about-to-start a build for a while now, and now that the kits are available, I'm curious how they compare to the parts list I've been sitting on.
 
Wow! It's early Christmas!!!

I take it this a test run, and I'm more than willing to give it a go! My only concern would be that, should something be missing, I would be stuck with 0 local availability.

6L6, since you already gave it a go, what did you find? Is everything really included?

Things that may not be there include:
- input "orange" safety capacitor (the one connected to star ground)
- RCA connectors (picture looks like there are at least input ones)
- Is there only one regulating option included? Are all? Which?
- I assume there are no 'on' or 'channel' leds, nor any option for front on/off switch?
- Transformer??? It is clearly shown in the photograph, but not on the text list

Also, not listed in the description:
- which OpAmp is included?

How 'soon' would you require feedback? Mine will take at least 20 days to arrive to me, and then it's chassis building time, so I'm not going to be able to dish out any feedback too soon.

Thanks for any feedback,
Best regards,
Rafa.
 
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Neutrik RCAs, a TRS jack, a knob (though size and color are omitted), wire, and a Schurter PEM (which I assume is the big switched one in the picture) are all listed as kit pieces, so chassis parts are definitely in there.

There is a little mystery beyond those parts and the resistors and caps though. The sheet in the picture of the parts does have IRF610 and IRF9610 listed on it. Could use a little more clarification though for sure.
 

6L6

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The chassis is not included, nor do we have a chassis yet, but the kit DOES include input RCA jacks, headphone jack, and switched IEC power inlet module. Because we plan the chassis, those parts need to be designed around and we needed to choose them.

The outputs are IRF610/9610 and the opamp Texas Instruments RC4580. The combo sounds great! Resistors are Dale RN series with the values printed on the side. :)
 
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