Ironamp Video Posted

[Michael Rothacher]

Thanks guys!

This is interpretation of Western Electric 25B triode amplifier ?
L'Amp versus Ironamp sound witch one is more transparent ?
Could be possible please discribe this subjective sound presentation

Yes, it's certainly an homage to the WE25B. Though I'd love to have some some more info on that one, if anyone would like to share.

They're both pretty transparent, and IMO quite special. I'm usually inclined to favor the latest project though, so I'm withholding any sort of sonic assessment for later. 🙂

@vdi_nenna
Keep at it. The guys are pointing you in the right direction. Search Youtube for Impedance + Reactance + Resistance and some good lectures will come up. And, as ZM said, continue to meditate on it until the lightning bolt strikes.

 

[generg]

Did I hear right in the video, the bias voltage for the gate varies from 15 to 24V to get the 350mA for the SIT?

Does this mean even in the same index group of the SK82 we can find such a big difference in parts?

That would correspond to my observation in Nelson's new SIT project.

Nice project, Mike! Is on my to do list.

Much SITting around, you, moss57, Juma, Nelson.....🙂

ZM were are you? Only ch (j)ocking...😀😀

 

[Zen Mod]

well , I drew few iterations of choke(d) and CCS loaded amps , almost universal - for anything you have in drawer ........ mosfet , shaded mosfet , SSouth , SIT , PapaSit ..... be it depletion or enhancement part

Donut series , posted somewhere here

and not mentioning some , of which some you know , not posted anywhere

for now , I tried (shortly) PapaSit in some blatant FW SIT clones , same as in choked SE

they're secure in drawer now , waiting final (both technical and visual) monoblocking

so much ideas , but not so much time

I didn't step in game in time , as Papa did ...... so still wasting time on other types of work

 

[Michael Rothacher]

Does this mean even in the same index group of the SK82 we can find such a big difference in parts?

Hi Generg,

I've purposely built some wiggle room into that figure. I don't have a large sample of transistors, so I don't know where the edges really are. But certainly the range is more than a volt or two.

I really like NP's push-pull amp from BAF. That'll be my winter project, and like everyone else here, I"m anxiously waiting here in front of my screen for it to drop from the sky. 🙂

 

[Michael Rothacher]

Naked prototype shot:

 

[nicoch58]

I really like NP's push-pull amp from BAF. That'll be my winter project, and like everyone else here, I"m anxiously waiting here in front of my screen for it to drop from the sky. 🙂

😛😛

edit
wow look gooood!
you need some nichel at the input ! 🙂

 

[generg]

I have measured as good as I could ten SJ28 and nine K82, so I dare to say that at 1,3A for instance the working point of Papas Push-Pull they differ around 4V.

So Mike it is really good to have some margin…..

there is one SJ28 KF instead of KE but he is not outside…….
As far as I remember the KE and KF was a pinch Off voltage and this marking seems not very important for matching for Iron AmP or the SONY AmP…..

Of course my input data I choose for the tracer are self-made without any deeper knowledge….

I am always happy to see at least a curve…..

the picture shows in red the SJ28 and in black the SK82..

So you see that it is possible to find close pairs!

😀

 

[Michael Rothacher]

Nice work there G! A 3-4V range for the N's would agree with what I've seen so far.

you need some nickel at the input !

I have some fancier ones from Lundahl and Sowter, but I haven't listened to them yet. For the published project I wanted to keep it all Edcor, and leave the tweaking fun to the experts. 🙂

 

[generg]

Edcor is so cheap and sounds so got.....!

😀😀

I still must hear the F6 with 1/4W Version instead of Jensen, with the 1/2W Edcors the sound got too much k2 ..... But I have to do it more thouroughfully ....😀

 

[nicoch58]

Edcor too bad that is in US.... 350ma ,for a single ended is big iron ,what price charge for that beauty ?

Michael ,like a Papa ones ,I m anxiously waiting here that you to drop from the sky the sonic assessment 😀

 

[generg]

Ironamp project video posted here:

Ironamp Project Video - YouTube

I hope you enjoy it. 🙂

I updated the captions if you want to try Youtube's translation option - should be funny 🙂

Hi Mike,

at the moment I cannot get access to your video, they say you closed your account.....?

 

[6L6]

Yes, the video link is dead. 🙁

 

[Zen Mod]

Mighty ZM already saved it to PC

will do the same tonight , just in case , with entire internet

 

[6L6]

Good idea.

Should I send you an extra Hard Drive?


🙂

 

[Zen Mod]

naah .....

I'm using Rahat Lokum for storage

 

[Michael Rothacher]

Due to a snafu with Google+, I had to re-do my Youtube channel. I lost all my subscribers and all my views. I'm bummed out, but my new channel is online now.

The new link: https://www.youtube.com/watch?v=FZymAeaVsAg

If I emailed you a link, that one won't work anymore. Sorry for any inconvenience.

I've updated the links in my original post and my blog. If you encounter any trouble, just let me know. 🙂

 

[generg]

what´s a "snafu"…..😀

 

[generg]

Edcor too bad that is in US.... 350ma ,for a single ended is big iron ,what price charge for that beauty ?

Michael ,like a Papa ones ,I m anxiously waiting here that you to drop from the sky the sonic assessment 😀

prices USA…….🙂🙂🙂
EDCOR - XSM10K/10K 12.97 USD

EDCOR - CXSE25-8-150
87.84 USD

prices Germany……..😱😱

Edcor XSM10K/10K, 23,79 €

Edcor CXSE25-8-5K, 142,79 € this is not the correct one, only to get an idea of the European prices.

 

[nicoch58]

Edcor too bad that is in US....

🙄

Ps better from US....circa 185€ pair inclusive ship+ import

 

[Michael Rothacher]

what´s a "snafu"…..😀

Zen Mod would ban me for saying it. 🙂