balanced x-Preamp

[Orgonom]

This is a variation of my sym. Headphoneamp
http://www.diyaudio.com/forums/showthread.php?threadid=12470
used as preamp.
You could use it asym. and sym.
The output should be used balanced for best perfomance.
Not build yet, but should work.
Powerdissipation is 5W each channel. You must use
a regulated supply. Have fun.

Andreas

 

[Orgonom]

forgot attachment!

Here is it.

 

[Orgonom]

Nobody intrested?

Seems that nobody is intrested in this design.
I will repost when prototyp is done.
Andreas

 

[loovet]

I do find your schematic interesting.

How about this PCB layout?

/loovet

 

[Orgonom]

Zip file doesn`t download!

Hi loovet,
couldn´t download your file.
Andreas

 

[loovet]

Re: Zip file doesn`t download!

Hi loovet,
couldn´t download your file.
Andreas

I can see that the file have been downloade at least 9 times.

Any one else who got the same problem?

If you still can't download the file i can e-mail you.

/loovet

 

[Orgonom]

I got it. Thanks for your work.
But could get it only with MS Explorer and not with NS 4.7 !???

To your PCB:
Take a look at my headphoneamp from the other tread. I put the mosfets back to back. Guess why?
Andreas

 

[loovet]

I got it. Thanks for your work.
But could get it only with MS Explorer and not with NS 4.7 !???

To your PCB:
Take a look at my headphoneamp from the other tread. I put the mosfets back to back. Guess why?
Andreas

The fets work more symetric if they have the same temp?

/loovet

 

[Orgonom]

as the transductanz vary with the temp - Yes.

Andreas

 

[Samuel Jayaraj]

Can this X-Preamp be made to work just as well with Pchannel IRF devices in place of the ZVP3306 (since I am not able to obtain them)? What are the changes that need to be incorporated? Can we have a schematic of this as well? Perhaps, this will generate more interest from everyone to couple this preamp with the Aleph-X amps.

 

[Orgonom]

Hi Sam,
first you have to change the p-channel fet of the currentsource to IRF 510 (610) because i dosn´t took care about power dissipation.(Too high for the small zetec device).
The input diffpair could be replaced by IRFD9110 (9120), but as the input capacitance is higher the distortion will rise.(of course you can take a similar p-mosfet with low input capacitance.

Bye Andreas