Pro Audio Design Forum

First, really nice job. Whether by wank, luck or unstated genius, that thing is quiet. From the schematic symmetry, this design looks to be a candidate for a "humbucker" board layout. My new word from another thread here on proaudiodesignforum. Please bare with my attempt to describe what ...

I just discovered the LMP2021. It has very low offset and it is pretty quiet.

I just couldn't get the choppers quiet in my circuit, though they are also working for me.

http://www.ti.com/lit/ds/symlink/lmp2021.pdf

Lower offset but only slightly so...LT1001AM. @ 15uV max, guaranteed, is the lowest Vos off the shelf opamp I know about. If anybody knows of a lower Vos I would be thankful to you if you would share the info. https://www.analog.com/media/en/technic ... LT1001.pdf

Hmm, or maybe I should say humm... I hadn't thought of that. I don't know how I'd stop myself from trying it now. Great idea!

It'd be somewhere around a mH. In order to get the best emi immunity, wire gauge should be as small as possible to enable optimal constructions of a smaller loop area. Up to maybe ten ohms or so series coil R is acceptable. Multilayer is fine. What I've seen, off the shelf looks nowhere close to opt...

good point, and it will be differential noise too. Not to mention the coil would need to be very near to other circuitry it could easily interfere with. That is definitely on my mind. I'd be looking for a low loop area coil and possibly try and come up with some kind of small, grounded steel shield ...

I believe it is pretty much as you described. We have a nice impedance analyzer at work where I can frequncy sweep various parameters . The high ripple current output filter ael caps drying out is essentially what determines our product lifespan. I have been able to catch snapshots at varying stages...

^^^^ oh yeah. Sorry if this is the wrong place for this.

The love of those big, well built, coincidentally low DA, audiophile caps probably isn't completely irrational. Would the magnetic complement to dielectric absorption be core material hysteresis? If high levels of filter energy storage element linearity is the goal then why wouldn't air core inducto...

If the fuses stop the explosions, it might convince me to consider straying from the flock. Hard to deal with, expensive parts that fail safe are better than not shipping due to long lead part sourcing problems. I've also experienced the cratering. Often the collateral damage seeming much more drama...