wow, nice, NOT JUST the brilliant sound tuning stripes on the relays 
, giving more sonor sound
, giving more sonor soundAn externally hosted image should be here but it was not working when we last tested it.
Very nice ZM!
Wow the balanced one is becoming high. No slim line cabinet.
Did you have a chance to listen to it?
( don't think so, there is no solder on the in-out pads
well , SE iteration is pcb sandwiched between two xformers , and can't be arranged differently , overall height is 95mm (so - take it or leave it , no slim boxes in my realm
)I/we did extensive listening and comparative tests of SE iteration , before I had pcbs made ; with pcbs (read - relay signal switching , not silly rotary switch) , it can only be better , though I'm doubting that I can hear difference , at least as long contacts in silly rotary switch are still decent
few pics from today enclosed , for general amusement ( and maybe some info)
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while SE is pcb sandwiched with two xformers , Bal iteration is one xformer per pcb , so two needed for stereo operation ; they can be mounted separately (each having height of ,say,55mm with bottom distancers) , or can be stacked one on top of another , with overall height of approx. 105mm
I did some listening tests of balanced iteration , hearing nothing worse than what I have heard with SE ......
I just finished completing first Iron Pumpkin (developing) prototype with Turtle (bal) modules ..... and sent it to second pair of trusted ears
that IP proto is nothing else than all modules separately - Good Geminis (shunts) , Iron Pumpkin Diamond buffers , selectors and Iron Turtles ;
I had , prior to Turtles , plain pots after selector and simple autoformers on output ..... now - pot is tossed , and Turtles in place of autoformers ....
I did some listening tests of balanced iteration , hearing nothing worse than what I have heard with SE ......
I just finished completing first Iron Pumpkin (developing) prototype with Turtle (bal) modules ..... and sent it to second pair of trusted ears
that IP proto is nothing else than all modules separately - Good Geminis (shunts) , Iron Pumpkin Diamond buffers , selectors and Iron Turtles ;
I had , prior to Turtles , plain pots after selector and simple autoformers on output ..... now - pot is tossed , and Turtles in place of autoformers ....
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Jfet's buffer for AVC help please
My autoformer volume control is single unbalanced and totaly passive version.
I see interesting Zen Mod work and think about add jfet's buffer to my AVC.
Bunch of Toshiba and LSK pairs screams in drawer to be used.
Can be superb to try bufferised version now but i need kind experts who show me adequate schematic for that purpose.
Last news i get 2 more autoformers ( first pict ) so i can build full balanced version in the future.
Some thing cascoded for low impedance or not ?
Please bring me solutions
My autoformer volume control is single unbalanced and totaly passive version.
I see interesting Zen Mod work and think about add jfet's buffer to my AVC.
Bunch of Toshiba and LSK pairs screams in drawer to be used.
Can be superb to try bufferised version now but i need kind experts who show me adequate schematic for that purpose.
Last news i get 2 more autoformers ( first pict ) so i can build full balanced version in the future.
Some thing cascoded for low impedance or not ?
Please bring me solutions
Attachments
for proper balanced and differential , you need balanced autoformer
otherwise , you'll have sort of balanced , made of two SE
as buffer , just use what's known as Papa's B1 V.2 - Toshiba JFet complementary buffer , ....... also seen as input of M2 etc.
for full blast (well , more like cheapskate) iteration - see my solution from PSM LS Cook Book (link in sig)
otherwise , you'll have sort of balanced , made of two SE
as buffer , just use what's known as Papa's B1 V.2 - Toshiba JFet complementary buffer , ....... also seen as input of M2 etc.
for full blast (well , more like cheapskate) iteration - see my solution from PSM LS Cook Book (link in sig)
will open proper thread soon , with all schematics and blahblah
first impression from Official Second Pair of Ears is something as "Hell , Yeah!"
first impression from Official Second Pair of Ears is something as "Hell , Yeah!"
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here it is , principle ( so ignore number of taps)
observe proper polarity of windings
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well, I'am a proud owner (and beta tester) of Iron Pumpkin, one on the pics from page 45.. after a number of iterations, Iron has been completely finished and its his final version.. I can say that I am very pleased with my small contribution (testing, testing) to the development of the preamp..
The device is silent, both on the SE and on Balanced inputs, caution of picking up some kind of electronic waste was unreasonable. The balanced part sounds very similar to the previous iteration, and the SE goes deeper then previous version. The character has remained the same, and 24 positions are enough to adjust the volume. And sounds great of course
In my system Nagra PL-L was replaced by Iron Pumpkin. Here is the my system where testing was done
Analogue:
Turntable: Kuzma Stabi S with Kuzma 4Point and Stogi Ref VTA 313
Cartridges: Benz Micro LPS and Ortofon SPU Royal N
Stepups: MA Cotter mk2 and Tango NN-600-50K
Phono preamp: Nagra VPS
Digital:
Audio Player: Marantz NA8005
Universal player: Marantz UD7007
DAC: m2Tech Young DSD with diy PS
Amplification and speakers:
Preamp: Iron Pumpkin (Nagra PL-L)
Amp: Babelfish J2 (Zen Mod)
Speakers: Tannoy 15" Gold Monitor in MLTL (Zen Mod)
The device is silent, both on the SE and on Balanced inputs, caution of picking up some kind of electronic waste was unreasonable. The balanced part sounds very similar to the previous iteration, and the SE goes deeper then previous version. The character has remained the same, and 24 positions are enough to adjust the volume. And sounds great of course
In my system Nagra PL-L was replaced by Iron Pumpkin. Here is the my system where testing was done
Analogue:
Turntable: Kuzma Stabi S with Kuzma 4Point and Stogi Ref VTA 313
Cartridges: Benz Micro LPS and Ortofon SPU Royal N
Stepups: MA Cotter mk2 and Tango NN-600-50K
Phono preamp: Nagra VPS
Digital:
Audio Player: Marantz NA8005
Universal player: Marantz UD7007
DAC: m2Tech Young DSD with diy PS
Amplification and speakers:
Preamp: Iron Pumpkin (Nagra PL-L)
Amp: Babelfish J2 (Zen Mod)
Speakers: Tannoy 15" Gold Monitor in MLTL (Zen Mod)
do you have a spice model of your AVC? Or its magnetic parameters? Would be nice so I could play around with buffer designs.