Pass HPA-1, what do we know?

EUVL,

This does not have to get into a squabble. There are reasons to use both approaches. If price wasn't an issue, two large transformers would be ideal but one transformer with separate regulators can come pretty close. At some point proper grounding(ground paths) can become more of an issue. ;)

On a different subject I am a big fan of the Pioneer Super Linear Circuit with a few mods but it is often not given its due. An excellent choice.

Jam
 
Rank No. 1 is the DAO SE.
The LU1014 in triode mode just has some unexplained magic.
The DAO SE all-FET Class-A ZGF Headphone Amplifier
DAO - Original-Ton

Rank No. 2 is our version of the Pioneer SL, with JFET buffer input.
Comes very close to the DAO.
But if you have a planar magnetic, then those who tried current drive love it to bits.
Current Drive for Headphones & The Super Linear Transconductance Amplifier

The UTHAiM with zero global feedback has a lot of drive and authority, but just lack some sweetness.
UTHAiM -- Just for Fun
The lateral TO3Ps you should try out some time, in Class A headamps.

All the above have no global feedback.

If one likes the feedback sound, then the F5X-HA is not bad.
F5 Headamp ?
(Someone sold his balanced Dynahi after building the F5X-HA.)

And some like the XELF buffer (again lateral FETs) with my discrete opamp much more than the WHAMMY.
The XEN XELF Headphone Buffer

One more thing.
Everyone who has tried our Passive Danyuk Crossfeed says it is a must have.
Dimitri himself incorporated it in his design for Linear Systems.
https://www.linearsystems.com/lsdata/others/Headphone_Amplifier_Evaluation_Board.pdf
Give it a try.

Enough advertisment (though we have all but stopped offering anything since Corona).

;)


Cheers,
Patrick
 
PiotrL,

The Toshibas have have a slightly clearer sound but suffer from low transconductance so two pairs would help like Patrick suggested, but you would add to the complexity and need additional heatsinking. You would gain some bass slam but I fear you would lose a little bit in the upper frequencies.

I have tried the Semi-Labs verticals with some success but still does not have the bass slam as the FQP devices.

A dilemma I face with my next design.........:)

Regards,
Jam
 
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meldano,

Most impressive build.................:cool:

Congrats!

Jam
 

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