Who decided on +/-18v

[user 37518]

fwiw the "HV" opamps I mentioned are used with such a supply arrangement as the input signal is switching +/- several hundreds of Volts (sitting on a bias voltage that may be in the magnitude of big kVs)

I remember reading some years ago an application note to implement a regular op-amp with kilovolt rails. Can't remember where it was or the manufacturer: Linear Technology? Analog Devices? Texas? I would have to check. I am still young, but I guess I am entering an age were stuff in my memory starts to get 'filed' rather than being readily available.

 

[Newmarket]

Yeah - sounds like APEX stuff to me. But they've been thru various corporatr ownership esp Cirrus

 

[user 133392]

Headroom anyone?

±600V rails.

 

[user 37518]

Got headroom?
View attachment 103919

Nice!!! Those opto isolators are definitely not the best for linearity, but if you want a 1.2kV peak-to-peak swing, that should do it.

 

[Newmarket]

Headroom anyone?
View attachment 103919
±600V rails.

Where is that circuit from ? It's very much along the lines of circuits I deal with in my (non-audio) employment.

 

[Newmarket]

Nice!!! Those opto isolators are definitely not the best for linearity, but if you want a 1.2kV peak-to-peak swing, that should do it.

Yes. Although (albeit I can't take a proper look right now) they appear to be in the overall feedback loop.

 

[user 37518]

Where is that circuit from ? It's very much along the lines of circuits I deal with in my (non-audio) employment.

Looks like something someone would do for marketing reasons.

IIRC there was a Rupert Neve Designs console with 120 V supplies.

Edit: I searched on Google, and noticed that there is a RND console with 90V supplies (I think it is +/- 45V, but the brochure keeps thing simple and doesn't specify).

 

[Newmarket]

Looks like something someone would do for marketing reasons.

IIRC there was a Rupert Neve Designs console with 120 V supplies.

Edit: I searched on Google, and noticed that there is a RND console with 90V supplies (I think it is +/- 45V, but the brochure keeps thing simple and doesn't specify).

Yeah - there's always the headroom issue - but it's probably all going to get squished down to ADC input levels at the end point.
fwiw my professional applications run SEM microscopes so the HV is a requirement.

 

[emrr]

I don’t quite have my head around the GE BA-5 tube limiter that’s +/-300V. Memory is audio path is + and side chain is -. But tubes are another story.

 

[user 133392]

Where is that circuit from ? It's very much along the lines of circuits I deal with in my (non-audio) employment.

https://proaudiodesignforum.com/forum/php/viewtopic.php?p=17089#p17089

 

[Newmarket]

https://proaudiodesignforum.com/forum/php/viewtopic.php?p=17089#p17089

Thanks. I see it comes from an EDN Design Idea.