Jfet BOZ

Damn, this look's good (and easy :D ) - BUT i was planning to make my future upcomming 2x F4 balanced mono-bloks. But as i see it, it is not possible to make this circuit balanced (unbal to bal converter is my only need through! as i only intend to run the signal balanced from pre ---> Poweramps).

Any suggestion's :confused:

Nelson Pass, i think you know the solution to this, what does it take for you tell hehe... ? :cool:

Thank's anyway for this great forum.

Jesper.
 
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lykkedk said:
................But as i see it, it is not possible to make this circuit balanced (unbal to bal converter is my only need through! as i only intend to run the signal balanced from pre ---> Poweramps).

Any suggestion's :confused:
..............


really piece of cake, but count on few additional things:

negative supply
doubling number of jfets (hehe - that's funny) to make LTP

CCS for tail of that LTP
at least one stereo pot per channel, if not balanced stereo pot

and you're there - balanced jfet BOZ
 
juma said:



Hi steenoe,
please help me understand how did you drive F4 to clipping with this preamp. Its power supply is 18V and it cannot be swinging more than 5-6V peak. It takes 20V peak to drive F4 to clipping.

Maybe I'm missing something?

Thanks

You are probably right. It was more likely the speakers that were tortured. In any case the J-fet BoZ can play more than loud enough with the F4. The speakers are Abby-clones with Fostex FE166's.

Jesper, take a look at the Pumpkin-mans :Pumpkin: latest creation also:) It should have gain and voltage swing enough for the F4. Very promising......

Steen:)

The Pumpkin

Lookie lookie, whats my dog doin' over there???:D
Poor confused thing, what happend back there?? Fart or something ?
Ratata
 
steenoe said:


Excactly, those eyes are hypnotizing;)

Steen:cool:

We can hide them, if you wish (Choky's eyes, I mean)
 

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ROVSING said:



Yes your probably right, might make this preamp to get something finished should be possible - i think i'll make it in 1 hour just to beat "Lucky" Steenoe:D

If you do the footwork, and go buy two cordless powerdrills, you can make one in like 30 minutes :)

The reason to buy two is that you use one charger for actually charging the batteries (you can get el-cheapo chordless drills sporting 18V), and one for building the amp in. The all you need to do is to swap the batteries from the charger to the preamp (which has a socket for the batteri since it's the box from the second charger), and off you go :)


Magura :)
 
Magura said:


If you do the footwork, and go buy two cordless powerdrills, you can make one in like 30 minutes :)

The reason to buy two is that you use one charger for actually charging the batteries (you can get el-cheapo chordless drills sporting 18V), and one for building the amp in. The all you need to do is to swap the batteries from the charger to the preamp (which has a socket for the batteri since it's the box from the second charger), and off you go


Magura :)


Very ingenious.:)
 
Magura said:


If you do the footwork, and go buy two cordless powerdrills, you can make one in like 30 minutes :)

The reason to buy two is that you use one charger for actually charging the batteries (you can get el-cheapo chordless drills sporting 18V), and one for building the amp in. The all you need to do is to swap the batteries from the charger to the preamp (which has a socket for the batteri since it's the box from the second charger), and off you go :)


Magura :)

Good idea. He is never gonna beat me. I can slow him down cause he needs the J-fets from me:D :devilr: Ups, forget them accidentally:D

Very ingenious.
Manu, you can just as well get used to that, when Magura is playing along;)
 
steenoe said:


Good idea. He is never gonna beat me. I can slow him down cause he needs the J-fets from me:D :devilr: Ups, forget them accidentally:D
Witch one of the Daltonbrothers do you want me to change your avatar to ?


You know me Steenoe, i could fill my walls with unfinished PCB's that i have laying around:D
I never put on the saddle the same day as i ride..
 
ROVSING said:

Witch one of the Daltonbrothers do you want me to change your avatar to ?


You know me Steenoe, i could fill my walls with unfinished PCB's that i have laying around:D
I never put on the saddle the same day as i ride..

Keep the dog, it gave me a good laugh:)
Do you put the saddle on the day after the ride? I think thats a bad idea:)

As for the Daltons, Magura is the obvious choice as Joe:D But I dont hope he ever change that avatar of his.

Steen:)
 
LAZY BOY HERE....

Any opinion as to whether this could be used as a unity gain buffer of sorts - with good results?

- or look elsewhere for simple

Basically I am thinking of playing with PLLXOs, but I'm thinking it might be better to stick the PLLXO between the pre and a very simple buffer - so I can swap amps out.

with ~105dB drivers this battry stuff turns me on

and

just tryin to keep opamps out - for the heck of it...


:xeye:
 
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mpmarino said:
LAZY BOY HERE....

Any opinion as to whether this could be used as a unity gain buffer of sorts - with good results?

- or look elsewhere for simple

Basically I am thinking of playing with PLLXOs, but I'm thinking it might be better to stick the PLLXO between the pre and a very simple buffer - so I can swap amps out.

with ~105dB drivers this battry stuff turns me on

and

just tryin to keep opamps out - for the heck of it...


:xeye:

lazy boy.........few posts upstream,before dangerman's pic
 
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mpmarino said:
Yup, lazy boy saw that. Lazy boy wants to be lazy - er and use the same v+.

OK, hows about lowering the gain on jfet boz >PLLXO>another lowered gain jfet boz>amp?

Lineup went thru some calcs earlier but he lost me somewhere in the middle .

:xeye:


me not see lineup...........my neck is blue :devilr:

make exact same stage
put 10k as gate stoper
return 10K from output side of output cap to gate

ya have buffer

phase?

try............ when you want simple supply