What To Do With Those 2SJ28's

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All will be revealed soon. And the names are just too good to announce early. :)

I think the first project will drop before BAF and the next at the show.

Caveat. Best laid plans, etc. etc.

No, not Slartibartfast. :)

Maybe even Ed Wood.

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Sure this autumn BAF be much hotter if compare with the cloudy summer in France.
Thx for exciting news :D
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Hi All,

I am curious about the pros and cons of a transformer as an voltage gain stage as opposed to adding extra active devices like a capacitor coupled BA3?

Without building several examples of each topology... Is there a consensus or a discussion (or even a list of pros and cons to contemplate)?
cheers

Beardy
(sitting on 3 pairs of 2sk180 and wondering about SIT-3 versus a BBA3/SE CD topology)

I get buffer with passive autoformer voltage gain stage now.
All my gratitude to Mr. Pass who give M2 schematic for greedy DiY boyz.
It's work and sound phenomenal. What we see SIT-3 have flat distortion versus frequency response.
Well with Edcor M2 i have enjoyable music reproduction and fantastic high resolution on 12'' full ranges without crossovers.
Non more active line stage in my audio chain.
Total silence noise floor.
Is only class A cd player + autoformer volume control + M2 + FR alnico drivers.
In near future after BAF i hope try diy version of SIT-3 with Papa blessing and crazy Uncle Mike new vfet amplifiers.
My kindest regards :)
 

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thanks for the autoformer , nice box ! as for the price we have not the same "affordable" definition :D
is there a subscribe list somewhere for the next SIT3 as i have missed the SIT2
the single end 2SK82 will suit well my onken horns :)

Autoformer with jfet buffer is a keeper 10 year is ~ 140 $ a year.
You save money on your electricity bill without active pre amp.
Subscribe are not offical but you can try contact by PM DiyAudio Team
maybe you can be the first on the list :cheerful:
SIT-3 have as well transformer voltage gain stage i think compare this single-ended sit with my actual M2 prototype.
Uncle Mike are mixturing bunch of new stuff and Zen Mod go Iron :magnet:
 
Does anyone have the datasheet for 2SJ27?

I got six pieces of these rare trannies from China recently, to check if they're real, I measured their Id vs Vds curves (manually, my curve tracer was dead since some time), one sample attached (Vertical axis in A, and horizontal axis in V) and it seems like they're indeed P-SITs with triode curves.

However, these curves look rather different than another 4 pieces of 2SJ27 I got from a trusted forum member before. So, I want to compare them against the datasheet, but Google didn't help me finding it so far.
 

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