Hi
Yes it should sound fine. This is pretty much the same as my USSA-1 except I had used output mosfet designed for audio ( not switching ) and used current sources instead of resistors to bias input stage. For me USSA-1 sounded better than my F5.
If you want something even more breathtaking still with bjt input see the USSA-5.x amp series. The USSA-5 with its very low degeneration on mosfet provides a greater class A envelope for the same bias. Latest 5.2 version uses all easy to find parts.
USSA-5 PCB GB
USSA-5 Build with Review
Fab
Yes it should sound fine. This is pretty much the same as my USSA-1 except I had used output mosfet designed for audio ( not switching ) and used current sources instead of resistors to bias input stage. For me USSA-1 sounded better than my F5.
If you want something even more breathtaking still with bjt input see the USSA-5.x amp series. The USSA-5 with its very low degeneration on mosfet provides a greater class A envelope for the same bias. Latest 5.2 version uses all easy to find parts.
USSA-5 PCB GB
USSA-5 Build with Review
Fab
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> USSA-1 sounded better than my F5
Did I read correctly that your V5.2 has THD of 0.0075% at 1W 1kHz into 8R ?
And what distortion did you get from your F5 ?
If I am not wrong, the First Watt F5 has corresponding THD at 0.0013%.
And a random F5X build has H2 0.0006%, H3 0.001% at 1W 1kHz into 8R.
May be the latest trend is "higher distortion sounds better". 😉
Cheers,
Patrick
Did I read correctly that your V5.2 has THD of 0.0075% at 1W 1kHz into 8R ?
And what distortion did you get from your F5 ?
If I am not wrong, the First Watt F5 has corresponding THD at 0.0013%.
And a random F5X build has H2 0.0006%, H3 0.001% at 1W 1kHz into 8R.
May be the latest trend is "higher distortion sounds better". 😉
Cheers,
Patrick
Hi EUVL
I am not sure why you compare THD with appreciation of sound…..🙄
Please don’t post in the tube amp section 😉
I had not measured my F5 before I sold it unfortunately. I know many peoples liked its sound at an DIY show.
Appreciation of sound is personal and sorry if I have offended you…
Anyway, see my USSA-3.2B with lower distortion - if that matters - which design is jfet input such as F5 but with bjt output. It has lower THD and is not better sounding but just different sound than the USSA-5.2.😉
In fact USSA-5.2 was tuned to have such H2. H2 can be adjusted with P3/P4 to be as low as H3 or even lower.
My class AB designs have lower THD also and they sound different but not better.
USSA-5 PCB GB
Fab
I am not sure why you compare THD with appreciation of sound…..🙄
Please don’t post in the tube amp section 😉
I had not measured my F5 before I sold it unfortunately. I know many peoples liked its sound at an DIY show.
Appreciation of sound is personal and sorry if I have offended you…
Anyway, see my USSA-3.2B with lower distortion - if that matters - which design is jfet input such as F5 but with bjt output. It has lower THD and is not better sounding but just different sound than the USSA-5.2.😉
In fact USSA-5.2 was tuned to have such H2. H2 can be adjusted with P3/P4 to be as low as H3 or even lower.
My class AB designs have lower THD also and they sound different but not better.
USSA-5 PCB GB
Fab
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Sounds like J2 is the amp for you.
Not for me. But then it is subjective.
Each to his own.
Cheers,
Patrick
Not for me. But then it is subjective.
Each to his own.
Cheers,
Patrick
I don’t know about the J2.
By the way I simply have to increase the feedback factor to get lower THD or increase output stage bias current. With Jfet input stage you need to have a low idss and for bjt is it even easier by reducing the input stage current.
Fab
By the way I simply have to increase the feedback factor to get lower THD or increase output stage bias current. With Jfet input stage you need to have a low idss and for bjt is it even easier by reducing the input stage current.
Fab