We don't need to agree. Each to his own.
I have examples of both. I can draw my own conclusions.
The Pioneer Super Linear Circuit
The DAO SE all-FET Class-A ZGF Headphone Amplifier
The DAO SE all-FET Class-A ZGF Headphone Amplifier
😉
Cheers,
Patrick
I have examples of both. I can draw my own conclusions.
The Pioneer Super Linear Circuit
The DAO SE all-FET Class-A ZGF Headphone Amplifier
The DAO SE all-FET Class-A ZGF Headphone Amplifier
😉
Cheers,
Patrick
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
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
Yes, I am usually not a fan of bipolar circuits.
But this one is currently our rank no. 2 for headphone amps.
😉
Patrick
But this one is currently our rank no. 2 for headphone amps.
😉
Patrick
And the one toroid shown in the DAO SE (LU1014 triode mode) is not what it seems.
It has custom windings with very low inter-winding capacitances, on top of an over-dimensioned core.
In both cases, completely separate secondaries, diodes, and regulators for each channel.
Patrick
It has custom windings with very low inter-winding capacitances, on top of an over-dimensioned core.
In both cases, completely separate secondaries, diodes, and regulators for each channel.
Patrick
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
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
Jam, what do you think about the idea of HPA-1 with 2sk/2sj Toshibas? Did you happen to try it yourself by chance?
I tried it....
SK/SJ have for sure the better resolution, the FQP have the better slam in the bass.
SK/SJ have for sure the better resolution, the FQP have the better slam in the bass.
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
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
generg,
Yes,unfortunately headphone amplifier design is a balancing act and you have to choose the compromises you make carefully for a successful design.
Regards,
Jam
Yes,unfortunately headphone amplifier design is a balancing act and you have to choose the compromises you make carefully for a successful design.
Regards,
Jam
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Yes, I can imagine that for headphones the FQP are the better choice.
As a pre situation changes.
As a pre situation changes.
Finished my HPA-1 Clone.
I am very happy with the sound as headphone amp and pre for my XA25 🙂
Pictures of your diy Pass amplifier
Thx to Jam and JeffYoung!
I am very happy with the sound as headphone amp and pre for my XA25 🙂
Pictures of your diy Pass amplifier
Thx to Jam and JeffYoung!
> You would gain some bass slam but I fear you would lose a little bit in the upper frequencies.
+1
That is why we used the 2SK1058 / 2SJ162 in the UTHAiM.
They have plenty of transconductance but are still very low in capacitance.
So ideal as output followers when biased at ~200mA.
Patrick
+1
That is why we used the 2SK1058 / 2SJ162 in the UTHAiM.
They have plenty of transconductance but are still very low in capacitance.
So ideal as output followers when biased at ~200mA.
Patrick
