The Singing Bush

[AnthonyA]

Which is most most musical of all the sit

Tuby

 

[Zen Mod]

Which is most most musical of all the sit

Tuby

hard question ... in fact easy , when you ask it on some fifi forum , not here

if you did ask , which of SITs is best , taking in account linearity , dissipation and all tech factors , then it's easy - 2SK77B is most probably best of all , easily implemented in whatever arrangement you can think of

not even counting fact that Pa said "this one is The Best"

with Singing Bush type of amp , result heavily depends of amp-speakers marriage; even if 45-50W is respectable for SE amp , you need sensitive and efficient speakers to use all raw and triodish quality of amp , while keeping it in lowest possible power range (using rest for dynamic peaks) , so having least possible THD

same applies to any tube SE amp ......

so , it is really more question of fact what you have (of SITs) on your bench ; if 2SK77/2SK77B then no brainer ; if THF51/2SK182ES then there is little more compromise

we'll see what we are getting with 2SK180 ; though - even if I'm hoping , I'm really not expecting miracles

if you don't have 2SK77/2SK77B and you vary of compromises , just make Schade iteration ...... that one was more cunning from Pa than primary one (with 2SK77B) , meaning - it's easy when you have jewel in your hand , while its harder to make jewel from brick

Pa, Mithrandir , Funny Alchemist

 

[AnthonyA]

Don't need that much powah actually.. Just something that's better than tube se. Slightly more pawah than 300b but better

 

[alheiz]

Perdón a todos.
Gracias por su apoyo!

 

[gpapag]

Please post in English only diyAudio Rules

"Sorry everyone.
Thanks for your support!"

George

 

[Zen Mod]

we'll see

my own personal Wakootalian , Mighty Bubba Flocchini , sent me a pair of these for testing

now they're on Customs , hope to get them sooner than lately was the case with lazy bstrdz

everything will stay the same , possible variations voltage potential of SIT Drain and values of resistances in Mu source

we are hoping that bloody thing is similar to 2SK77B , and as we all know , hope is dying last .......

while mine , from Bubba Flocchini, are still Customized , got them suckers , freshly arrived to my (local) Buddy

will spend some time these days to test them , and after arriving of second pair , will test these too

as I said - hope never dies - we'll see how they're close to The Best Ones

 

[V FETish]

as you probably know , I was on Pilgrimage (end of last year) to Sea Ranch .... to have few walks by the Open Ocean , collect some wood flown to shore ..... and to remind Pa that life isn't serious thing at all

Awesome thread and thanks.

Very nice to see yous standing together and very wonderful to see yous SIT'ing together too!

 

[Zen Mod]

as Pa is getting ......... wiser , it seems he's developing tendency of becoming more serious

so , it'll be cunning to visit him annually , to prevent further increase of seriousness

 

[V FETish]

as Pa is getting ......... wiser , it seems he's developing tendency of becoming more serious

so , it'll be cunning to visit him annually , to prevent further increase of seriousness

Very cunning indeed!

 

[wengtech]

while mine , from Bubba Flocchini, are still Customized , got them suckers , freshly arrived to my (local) Buddy

will spend some time these days to test them , and after arriving of second pair , will test these too

as I said - hope never dies - we'll see how they're close to The Best Ones

that's very cool
can't wait to see the results

 

[Zen Mod]

Lazy Sunday .......

so no testing 2SK180 today

maybe tomorrow , but most probably day after

in a meantime , here's Trade post : The Singing Bush Kits

think hard - do you need it , are you happy with 130-180W of heat per channel...... which iteration is right for you etc.

....contrary to some latest concoctions , this one is easy to set and forget , but as any , it demands patience and care in assembly

 

[ggetzoff]

so no testing 2SK180 today

maybe tomorrow , but most probably day after

in a meantime , here's Trade post : The Singing Bush Kits

think hard - do you need it , are you happy with 130-180W of heat per channel...... which iteration is right for you etc.

....contrary to some latest concoctions , this one is easy to set and forget , but as any , it demands patience and care in assembly

Choky,

I ordered the Singing Bush kit because we don't have enough heat in Arizona

Can't wait for those 180 measurements....no pressure.......

 

[Zen Mod]

2SK180: Hope never dies ....... but, Oh Boy , how it's Dodo now!!



pair sent by Bubba Flocchini are still Customized , and I did put today first one (of pair) my local Buddy obtained

initial setup , as hope (that it's close/r to 2SK77B) commands , same as ZMighty Singing Bush - rail 60Vdc , Iq 3A, Mu resistor set 0R2 up, 0R2 down, speaker output from middle ,Drain potential smidge bellow 30V

first stint - 1W THD Spectra measurement - damn!! 1.76%

power down , insert additional 2pcs of 0R1 in Mu string , power up , set Iq to 2A2 , Drain at 35V , try THD with 0R4 up and 0R2 down , then with 0R2 up and 0R4 down

THD shows that better option is 0R4 up and 0R2 down

few pics of setup

 

[Zen Mod]

2SK180 Singing Bush , 8R load

gain is 330mV in for 2V828 out , so 8.57V/V , 18.66db

 

[Zen Mod]

2SK180 Singing Bush , 4R load

gain 338mV in for 2V out, so 5.917V/V , 15.44db

 

[Zen Mod]

2SK180 Singing Bush, conclusion

well , behavior pretty much the same as THF51 and 2SK182 , maybe little more leaning to 182 side

was it worth spendiong money and repeating all measurements , to find out how hope is mortal?

considering that this time I didn't engaged my wallet, ( as was the case with 2SK182 for SissySIT)first part of question my Buddy and B. Flocchini need to answer

measurements - it was my pleasure , as always is , when I have something to play with

hope is maybe mortal , but we Kids are immortal !



one thing more - if you look back at what's posted in #57 , my fave commercial toob amp - EAR 859 - situation with any iteration of Singing Bush is simply more rosy

and , THF51/2SK180/2SK182 iteration , being slightly scaled down to 132W of heat per channel , is somewhat easier to make , as little bonus to decrease in performance , when looking at ZMighty Singing Bush with PapaTokins

I will repeat measurements , probably tomorrow , with second 2SK180 specimen , but now really not expecting Miracles

 

[Zen Mod]

Choky,

I ordered the Singing Bush kit because we don't have enough heat in Arizona

Can't wait for those 180 measurements....no pressure.......

well , contrary to Jim , who's flying those sissy little jets for diamond clientele, you can make a pair of these and put in your cockpit

 

[flocchini]

"was it worth spendiong money and repeating all measurements , to find out how hope is mortal?

considering that this time I didn't engaged my wallet, ( as was the case with 2SK182 for SissySIT)first part of question my Buddy and B. Flocchini need to answer "

It's all part of the experiment and what was learned

no regrets here

Will do the Singing Bush with THF-51S guessing 180s will find a home in another build (always optimistic

Thanks ZM for all the effort !!!!

 

[ggetzoff]

well , contrary to Jim , who's flying those sissy little jets for diamond clientele, you can make a pair of these and put in your cockpit

And since I am a spoiled pilot, I'm going to ask you to go a bit farther with you measurements. I have a 4 ohm loudspeaker, can you look at different rail voltages for 4 ohm load to see what rails would give me best case H2 scenarios? I realize the VFets are going to be different. And on that note, I wonder if the higher VGS parts do better with H2 dominance.....

 

[Zen Mod]

will do what I can with specimens I have