Helios thread

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rotheu, i am working on those inductors right now, gettting them to work without resonance in the audio band, piece of cake, literally...
Or did I mean pie....yes..make that pie.
Apple pie. With a thin crust, topped with maple syrup and ice cream.
4 twenty kind o treat.
 
I just want to thank everyone for their efforts on this :thumb:

I'm definitely in on this one if you guys can get it going :green:

This also might sound dumb... but the only reference I have to even coming close to hearing a HELIOS is the UAD EQ plugin. It is by far my favorite EQ plug for several things. I know it's not "real" but if it even resembles how the originals works then... :green:

The shape of the mids, the low shelf/ bump & the high shelf are ALL KILLER :!:
 
rotheu, i am working on those inductors right now, getting them to work without resonance in the audio band, piece of cake, literally...
Or did I mean pie....yes..make that pie.
Apple pie. With a thin crust, topped with maple syrup and ice cream.
4 twenty kind o treat.

Hi CJ. I didn't visit the forum for long time, just saw your post. Did you get anywhere trying to get them to work? What's the idea behind it? Thanks a lot.

rotheu
 
A long time went by now,
But how did your projects go?

Any more results since the prototyping stage?

Does anyone still have the schematics?
all the links are dead now and I would really love to study this project and prototype a unit.

Thanks
 
Would this help?  ;D

I've never seen this anywhere else before. I found it listed in the photos of a channel strip in an Ebay auction. If anyone has a problem with me posting this let me know I'll take it down.

This is the best one I've ever seen though. Enjoy :)
 

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kpearsall said:
Would this help?  ;D

I've never seen this anywhere else before. I found it listed in the photos of a channel strip in an Ebay auction. If anyone has a problem with me posting this let me know I'll take it down.

This is the best one I've ever seen though. Enjoy :)

Thanks really good actually,
it's clean and it has the schematics for the full module.
Thanks

I think that the circuit probably differs between different schematics, the transistor arrangement at least seems different.
 
If anyone's curious, that was from the musikladen console. Made my day when I found it and it had the HPF section with line amp in there :)
 
kpearsall said:
If anyone's curious, that was from the musikladen console. Made my day when I found it and it had the HPF section with line amp in there :)

Yes it is.  There are actually three different versions of that schematic.  The main difference is which amp cards are being used, and also the extra filter switch.
 
There was a -24V version of the line amp (15C1) and then later, a +24V version (2128)

If you look at these two moduels, the schematic is the same, although note that the 2128 schematic is incorrect, as the PNP and NPN transistors should be swapped (it should read 2n4058, then 2n3707, 2n3707).

 

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Hey guys I just got in a 500 series helios type 69 module. Anyone who is interested in working on a project based on this, pm me.
 
I've read through this thread several times, trying to determine the values of the inductors.  From the schematics, there are two different midrange versions, one with a single tap, and another with two taps.  I gleaned a bit of info, but have a few questions.

I did see what were apparently the values for the two tap version:  19.7 mH/37 mH/345 mH.  Can anyone verify that, and does anyone know the DC resistances?

I couldn't find any info regarding the midrange inductor with just a single tap.

The LF inductor is apparently 10H, but I never saw any DC resistance info.

Or maybe I just got lost in the thread  LOL!

Thanks.

Bri

 
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