[Currawong]

Quote:

Originally Posted by luvdunhill /img/forum/go_quote.gif I'd be more interested in which direction that audio-gd crap would swirl upon being flushed.

Have you experience with them?

 

[leeperry]

Quote:

Originally Posted by Currawong /img/forum/go_quote.gif Have you experience with them?

don't pay attention to this guy, he's just a troll...he threadcrapped one of my threads w/ dumb comments like this already.

I really think it's time for you to try AD797B anyway

 

[haloxt]

lol leeperry, sometimes you sound as crazy as the guy in your avatar looks.

How do you think the AD797B compares to audio-gd's HDAM's?

 

[Pacha]

Quote:

Originally Posted by haloxt /img/forum/go_quote.gif lol leeperry, sometimes you sound as crazy as the guy in your avatar looks. How do you think the AD797B compares to audio-gd's HDAM's?

Read this in case you didn't know anything about him :
Serge Gainsbourg - Wikipedia, the free encyclopedia

 

[leeperry]

I've A/B'ed AD797BR/LT1028ACN8 again...well, it's a knock out! AD797B has a much more versatile SS on the Z axis, but LT1028A has a much thicker sound, much wider X SS, w/ a very impressive percussive and deep low end bass response, a huge triangular SS(no need for crossfeed to get a front channel on headphones!) and slightly rolled off trebles, allowing to avoid EQ to kill middle ear resonances altogether.

I can only +10000 what RS said about it: http://www.head-fi.org/forums/6402627-post77.html

this thing is what PRaT is all about, they should have called it LT627-31337ACN8 and sold it for $80 a pop

also, AD797B likes to annoy you w/ tiny details noone cares about..

I wish I could try Burson V2 in my Firestone Spitfire, but the damn thing needs 38mA and its discrete linear PSU cannot feed more than 200mA...the manufacturer advised me to forget about it

LT1122A is also nice, possibly a good option to feed a "dirty" external amp..

 

[diditmyself]

Do you know if the Audio-gd people read this thread? Are they open to creative criticism and ready to improve their modules?

 

[leeperry]

BTW, I understand why AD797 is strongly frowned upon in CMoy's!

on a cheapo soundcard(Auzen X-Raider 7.1), 2*LT1028CS8 output 0-1mVDC...but 2*AD797BR 100mVDC!!! lesson learned

 

[haloxt]

Quote:

Originally Posted by diditmyself /img/forum/go_quote.gif Do you know if the Audio-gd people read this thread? Are they open to creative criticism and ready to improve their modules?

I've read several times that audio-gd tries to read all threads about their products to gather user feedback and ideas for improvements. If you have some ideas, share and they might use it. Some versions of the hdam's have been updated to reflect user preference and might be updated even more if enough people ask for some change. I like how the three hdam's are right now, three totally different sound signatures and fun to play with.

 

[diditmyself]

My experience is limited to folded cascode circuits like Earth. I have less experience from standard opamps like Moon or complementary amps such as Sun.

Improvements on Earth will make it an AD797-clone.

The simple SK170 input stage sounds warm and fuzzy and nice in a way but not clean. It's not obvious everyone would like "improvements" here, but cascoding improves details and soundstage. The sound is leaner with a more forward presentation. CFP is an alternative and also improves details and make it leaner.

SA970/SC2240 sound hard, typical solid state. To my ears SA1016/SC2362 are better.

A bipolar input stage might sound better but introduces problematic bias currents that has to be dealt with. My favourite input stage at the moment is bipolar CFP.

Applying a floating current mirror and shunt transistor to the folded cascode stage as in AD797 make it sound much better without compromises. Just cleaner and more enjoyable. I think many would describe it as "space around instruments" or "blacker background".

It's a couple of more transistors, but I think it's worth it. I don't think the basic folded cascode circuit can compete with the best monolithic opamps, and why do discrete opamps that sounds worse when they're larger and more expensive, often draw more current and have worse output swing.

To be discovered: if cascoding the folded cascode improves things, if the combination of cascode and CFP is as good as I hope, how a cascoded bipolar input stage sounds

 

[haloxt]

I forgot to say, Kingwa, the owner of audio-gd and the one reading the forums, doesn't have very good English

there's a chance he won't fully understand your informative post.

Did you ever get a chance to listen to the earth btw?

 

[leeperry]

yay, I just compared LT1028ACN8 Vs LT1028CS8 in the Firestone Spitfire(fed w/ ±12V)...huh, headshot!

OTOH, AD797BR only outputs 3/4 mVDC

 

[Currawong]

diditmyself: When the Sun first appeared, Kingwa asked a few people who had bought the Earth to try it out. The response was a bit negative (IIRC it was too bright), so he changed the circuit. I'm sure he'd be interested in your comments if you emailed them to him.

 

[les_garten]

Quote:

Originally Posted by leeperry /img/forum/go_quote.gif BTW, I understand why AD797 is strongly frowned upon in CMoy's! on a cheapo soundcard(Auzen X-Raider 7.1), 2*LT1028CS8 output 0-1mVDC...but 2*AD797BR 100mVDC!!! lesson learned

If you wanted to put a Few 797's on a BrownDog to substitute in place of an Earth, which ones wold you use?

 

[leeperry]

Quote:

Originally Posted by les_garten /img/forum/go_quote.gif If you wanted to put a Few 797's on a BrownDog to substitute in place of an Earth, which ones wold you use?

there's a dual AD797BR chinese seller on ebay, I wouldn't look any further...cheap and ready to use right away.

 

[les_garten]

Quote:

Originally Posted by leeperry /img/forum/go_quote.gif there's a dual AD797BR chinese seller on ebay, I wouldn't look any further...cheap and ready to use right away.

So anyplace you might use an Earth Dual OPA, you could substitute one of these? No worries about Voltages or outputs?