"WHAMMY" Pass DIY headphone amp guide

About the FET's in the output-stage: The 2SK2013/2SJ313 are about 8 times the cost of the FQP3P20/FQP3N30... Are they also 8 times better? I can't imagine...

Can somebody comment on that, please?

btw, I understood the IRF9610/IRF610 are likely to be replaced by IRF9610N/IRF610N (switching applications) by the suppliers, so I won't buy them.
 

6L6

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I've built a Whammy with K2013/J313 and with IRF610/9610. The Toshiba mosfets might be a bit better, but I'm honestly not sure if that was confirmation bias or an actual change in sound quality.

Wayne has verified that the FQP parts also work perfectly and sound great. Every time I've used them in different projects I have been extremely happy.

So the short answer is this - use whatever Mosfet you can easily get, and experiment with opamps for a change in the amp's sound.
 
I've built a Whammy with K2013/J313 and with IRF610/9610. The Toshiba mosfets might be a bit better, but I'm honestly not sure if that was confirmation bias or an actual change in sound quality.

Wayne has verified that the FQP parts also work perfectly and sound great. Every time I've used them in different projects I have been extremely happy.

So the short answer is this - use whatever Mosfet you can easily get, and experiment with opamps for a change in the amp's sound.
Thank you very much for answering my question so quickly ;)

Guess I'll go for the FQP fet's...
 
if someone wnats to try something new...

i've been toying with 2sk1058/j162 a bit for f4 duty and it is tough for me to assess them a weakness, whether i'm using my speakers or headphones.

i have not compared them directly to a pair of toshiba k2013/j313 directly, but i'm sure they would be very fair competitors
 
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1)indeed different pinout i should have mentioned...still.... may be worth the mod.

2) indeed that topology in the thread you linked is worthy of attention. I'm currently auditioning different variations (output mosfets,mirrors,feedback,output mosfet buffers,etc)....at the moment i am evaluating a through hole «euvl diamond buffer» ;)

Also i 've been trying regulated series supplies for the output stage....it's tricky :they color the sound but gives better «dynamics» compared to cap bank.

Ok enough thread jacking :judge:
 
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After some digging I found one that looks good. LS is 22.5 vs 22 but should work. Mouser - 594-2222-336-10224 X1 rated.

6J6 I saw you used 35v Nichicon FGs for C3, C4, C9 and C28. Assuming 50V parts are for additional headroom/longevity but not mandatory? I'd like to try to shoehorn some Silmics in there. Also, what is the value of the orange capacitor referencing safety earth and signal ground. TIA!!

Apologies for my last post, this has already been answered.
 
Finished my build tonight, thanks @6L6 for the quick replies and help. It turned out awesome.


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