Kt90 Pse

[Mikewong]

I just finished my ARS KT-90 PSE
running with 440 V at 88ma/tube with fantastic sound and surpases in almost every aspect as compared to PP mode.
And is it advisible for me to drive these tubes further at 100ma to gain a bit more watts?

 

[Geek]

Hi,

It's rated 50 watts dissipation. You're running it currently at 38.72 and 100mA would take it to 44W. If your supply B+ is fair stable, I'd say go for it

 

[Mikewong]

Thank you!

 

[richwalters]

Just to let know.....I've been very let-down with KT90's....I did a sub for an 88 amp running at 550V and the KT90's couldn't handle the B+. Funny enough I put a JJ KT88 in and it performed better than a KT90!
The KT90 is supposed to take 600V in UL easily. Noway



richj

 

[Tweeker]

Late KT90 production is reportedly quite inconsistant.

 

[rwellerson]

Which KT90 brand name?
EI or EH?
I've read the EH are wonderful and much better than EI nowadays....
Old KT90s from EI are known to be much better than newer ones from their fabrication.

[ ]
Ricardo

 

[Tweeker]

EI.

 

[Mikewong]

The KT-90s I used were bought in 92 from ARS,USA in matched quad
and still going strong after 8 full yrs of service. And starting last, the tubes were used in PSE instead of PP offering around 22watts driving the Celestion SL-60. Within normal listen level,the combinations deliver more details, better separation and more highs as used in the PP mode.
And I love it.
,

 

[jane]

I just finished my ARS KT-90 PSE
running with 440 V at 88ma/tube with fantastic sound and surpases in almost every aspect as compared to PP mode.

Do you want to share the schematic with us?

Jan E Veiset

 

[Mikewong]

My EL34PSE is based on this schematic.
And credit should go to the original designer.