SissySIT P ..... or how I proved fact of making more Hats than Pa did

[Zen Mod]

Well, anyone at least partially partial with my omnipresent babbling, knows about endless series of M2 derivatives, I made sorta recently
All of them having M2-like Front End (my biggest Fetish), so entire voltage gain got from autoformer, so no (overall) NFB involved
Also - all of them having second of my recent Fetishes - Square Law OS

Ok, that is line of unnecessary long line of M2 derivatives, difference amongst them being that each is having different quirk of OS parts

Then came next fixation point... when I concocted FE for Babelfish XA252, biggest part of invention was proper name for same FE - Plethora of Pinjatas ....... so I ( naturally) came to idea of making second totally unnecessary line of derivatives, now having Plethora of Pinjatas FE, and simply varying already proven SL OS iterations

This line having slightly different ( sorta mirrored/flipped/downundered/whatever) biasing mechanismus, comparing to older specimens, this one directly taken form Babelfish XA252
Comparing to older ones ( having opto between Mosfet Gates and fixed resistors from rails to gates), there are current mirrors from rails to fixed resistor(s) between Mosfet gates; result is better Iq behavior in domain of rails change, same as better Iq behavior in thermal change domain, and also firmer relaxation factor (Iq stability in dynamic domain; think recovery time if change occurs with long large signal)

Anyway, let's ignore Babelfish XA252 as first one, declare SissySIT P (P suffix for Plethora of Pinjatas family) as first one

Am I happy ...... yes! (this one done, so I can think of working on next )

Confirming same amp sound character, for amps made without NFB and with Autoformer gain and amps made with sorta heavy NFB and active gain ....... well, not exactly a novelty per se

this post intentionally made pic-less - in case of later edits, lesser mess

 

[Zen Mod]

some fancy prepared pics

 

[Zen Mod]

now some not so fancy pics

1/2

 

[Zen Mod]

2/2

 

[Zen Mod]

Proof is in da Pudding ( or how me Mom always said - eat your Porridge if you wanna grow strong and handsome!)

Rails +/-24Vdc-ish, Iq 1A7-ish

Load 8R

 

[Zen Mod]

Second Jar of Porridge

same conditions, 4R load

 

[Zen Mod]

How it sounds?
Well, as close Cousin ( younger one) of Babelfish XA252 SIT

Good enough for Mighty Moi

 

[adason]

You have been busy ZM!
Nice work.

 

[dBel84]

but can it be any good with only one green LED ??

 

[adason]

I am sure you can 'mod' it with blue led for more advanced builders

 

[Zen Mod]

yeah, and it would not even call for change of R124

what's few mA up or down, between friends ?



oh yeah, ZM clumsy as always - R124 actually being 43R

still enough current, while not being overenthusiastic, heat-wise

(Uled- 2*Vbe)/R124

so (1V93-1V3)/27R=23mA
or (1V93-1V3)/43R=14.6mA

 

[andynor]

Goddammit!

neverending omnipotence making it impossible for greedy boyz to decide next build.

I keep wondering what it would sound like with red caps and white pots

If I can’t stop thinking bout that, I might just have to build one. Or LuDEF. Or 252. Hmmm.

 

[dBel84]

I am ready when you are , the Bablefish XA252 was next on the list but this might offer better heat management for the chassis that I already have ( as opposed to making one from scratch )

 

[MEGA_amp]

you're making my head hurt

 

[codyt]

Lookin good!!

 

[Vix]

Congratulations Zen Mod!
Excellect work.
And, as as always, thanks to Nelson Pass for endless inspirations...

P.s. The more I think about the work that ZM has done, all those amps...he reminds me of an excellent DJ, the one who made perfect remixes, which often surpassed the original songs...

 

[Zen Mod]

as I know that someone will ask me that, here it is, in advance

SissySIT P signal path, simple as it can be

 

[Zen Mod]

and, while in Office

SissySIT P block schm.

as Pa would count it , two stages, plus two half stages

( how would Dr. Haus comment ?
considering M2 derivatives, where we have - half stage, xformer stage, half stage ..... so by ZM Count - no stages at all!)

 

[TungstenAudio]

Needs more green LEDs



I'm sure it sounds wonderful. I'm still trying to catch up with N+3 amp building.

 

[Zen Mod]

well, we can do that
ZD101 and ZD102, each can be replaced with 4pcs of 10mm Green Led