[zapel]

Apheard, have you had a play with the AD797 for any of your projects? how does it stack up. Thanks

 

[Apheared]

Z, I got some 797s here somewhere... I got them a few months ago about the time I started working with ppl on the insane portable... never got around to tryin em.

Gimmie a few days, I'll play with em over the weekend and get back to ya...

Anyone? experience with this IC? speak up!

 

[ppl]

My issue with the AD-797 is the High input Bias currents allowing the DC offset to change quite alot as the Volume control is rotated. This is a Problem with most Bipolar input Opamps. More over the AD-797 as well as other similar OPA's LT-1028, LT-1115 to name just a few are intended for High gain Phono and Mic Preamps rather than Line Level stages. To get rid of this problem an input Coupling Capacitor is required and i for one wount go their.

 

[Apheared]

Ok, the test.

It sounds ok. Very good offsets, with low value Rg/Rfb you don't need to compensate it. It has a decomp pin, and it functions (course something like a hansen has no room for this, nor a shunting cap across Rfb which you'll want)

It does ok driving headphones directly. I'd personally not use it w/o a bufferstage, either discrete or IC.

It's not that engaging of a chip. Kinda a dry sound. Probably accurate, but as an amp... hmm, maybe. I'd want to follow the datasheet and make a specific config for it, not drop it in an existing layout.

It's not for things with high source impedance; 1k is about it. This is for noise specs, it does still work fine with a 10k source.

Hmm... It's a great chip, I'm sure. but as-is, alone and unbuffered, I think I prefer other chips over it.

 

[zapel]

Apheared, Thanks for your efforts and information on the 797. I'm just making your little amp with the dual opa's and have a pair of SR60's on the way.
z