Ironamp Video Posted

[juanitox]

nothing magic just regular lundahll power choke

 

[dimkasta]

Part number?

 

[juanitox]

LL1638 lazy boy

 

[dimkasta]

Damn... I need more free time... And more money for nothing... And chicks for free

 

[dantwomey]

You can have a look at my completed Ironamp here.

http://www.diyaudio.com/forums/pass-labs/166784-pictures-your-diy-pass-amplifier-329.html#post4393420

Regards,
Dan

 

[wdecho]

Michael, Can this amplifier be built with the 2SJ28 of course by reversing the voltages with the source + and the drain - with a positive bias at the gate? I understand that one has to be careful with the bias to put on enough brake. The 2SJ28 is now available from circuitdiy whereas the 2SK82 is not.

 

[Michael Rothacher]

Yes, that will certainly work.

 

[wdecho]

We just need an adventurous soul. I am pretty good at following directions but not designing electronic circuits. I only have 2 2SJ28's and do not want to burn them. Received them today from circuitdiy.com. Great seller, fast shipping. I do have 2 pairs of 2SK82's and 2SJ28's I am saving for CSX1 or CSX2. Still deciding. I hope boards are available soon for the CSX2. I would never try to make that amp with proto boards.

 

[dantwomey]

Yes, that will certainly work.

That would be interesting. Same circuit only reverse the + and the -?
I am still only the 'honeymoon' but my Ironamp absolutely sings!

Regards,
Dan

 

[dantwomey]

More IronAmp pics here....http://www.diyaudio.com/forums/pass-labs/166784-pictures-your-diy-pass-amplifier-330.html#post4406953

Regards,
Dan

 

[plasnu]

Do you guys think if this will work?

I'm a novice and this is the very first amp I made up on LT Spice which I just learned with excellent Michael's video (Thanks you!).

On LT Spice, 2A, 20V(ds), Bias 4V, 6.7dB gain, 0.27% distortion@8Vpp output, -1dB @30Hz.

1. Self Bias, PSU is Universal PSU for DIY Aleph J. +-24V ( I have one)
2. Choke is 0.1H 2.5ohm ( I have a pair here)
3. Input Transformer will be 600:600

If it would work in real world, I have a few questions:
1 I'm worried about the inrush current and bias at the startup.
2. How about output DC offset adjustment and drift with temp change.
3. -24V DC on the input transformer is OK?

Thank you in advance

 

[plasnu]

I updated the schematics.

I started this modifying ironamp, but now there is no relationship to ironamp anymore, so I will post the updated model to L'amp thread. Thank you.

http://www.diyaudio.com/forums/pass-labs/201655-lamp-simple-sit-amp-217.html#post4428967

 

[Soundhappy]

@ Diyers
Last findings about similar to Ironamp but from Japan Nakazawa Hiromitsu San who use THF-15 Tokin

 

[Soundhappy]

More construction details

 

[Soundhappy]

and

 

[nagini262]

I'm trying to diy Ironamp for my friend. I will update more pictures....

 

[Zen Mod]

move chokes further from tone xformers

 

[nagini262]

move chokes further from tone xformers

Thanks! I will....

 

[Zen Mod]

xformers are canned , but input/output wires are still prone to go berserk if exposed magnetic fields

 

[nagini262]

I finished the Arch Nemesis and this is the Ironamp
Hope all of you like it
The sound is good for both