|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
86.140.68.52
In Reply to: It is a question of "too much gain" posted by Lou S on January 20, 2007 at 18:45:09:
You can't just up the closed loop gain from 1 to 5 in most practical circuits without all sort of ramifications.Poster was looking for a drop-in, not to re-engineer the amp. Doing this kind of stuff without a 'scope and knowing how to use it IS fraught with danger.
I have fixed quite a few amps where inexperienced tweakers have inserted parts with x20 GBW compared with the original and then wondered why it sounded bad. They could not see or hear the 60Mhz oscillation.
As I stated, Both the 627 and the 637 are the same part and have the same gain but different dominant pole compensation.
Cliff
First monolithic op-amp I used, the Fairchild uA709 in 1972(ish). Prior to that used Philbrick 2 tube and semi hybrid op-amp modules.
Follow Ups:
"You can't just up the closed loop gain from 1 to 5 in most practical circuits without all sort of ramifications."That was what I was saying. I have a 100MHz scope but don't waste time doing this sort of thing when there are myriads of drop ins. The question was why it was not drop in, the difference is in the closed loop gain, unity verses 5. The open loop gain for what was it, 112db, has nothing to do with why it is not a drop in replacement. One component is all it takes to make all the difference.
Best Regards,
.
Best Regards,
This post is made possible by the generous support of people like you and our sponsors: