ATAT
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AD8066 / OPA132 - BUF634 on quiescent, measures 20mA max, 15 typical, 10 minimum into RS-1s at max volume.
Originally Posted by Filburt Try the AD826 if you can find it there. I'm curious about the sound with it. Edit: ugh...8066 |
Originally Posted by ATAT The AD826 is bipolar input.. so special care would be needed to run that in a default gain of 11.. Id probably use it for gains of somewhere around 2. |
Originally Posted by quicksilver96 Isn't the AD826 a bipolar input? |
Originally Posted by rsabo I thought that op-amps get more stable as gain increases. |
Originally Posted by Filburt ...yes. So are some of the other chips we've been looking at. Bipolar input isn't some sort of unmanageable thing |
Originally Posted by NeilR I think the idea behind that is that bi-polars tend to generate DC offset and the more gain the more offset you have to deal with. |
Originally Posted by Filburt *shrug*...I haven't had too much trouble with offset on bipolars either in the PINTs I've made or in my test box (which has, at times, been running at gain 11). So, I think we may be OK |
Originally Posted by NeilR I was just referring to the general nature of bi-polars, not specifically any particular circuit. Although you didn't have a lot of trouble with your Pints (nor I with mine) the design of the circuits tends to optimize (minimize) input offsets as opposed to optimizing other things (such as noise) , and I think that is part of the reason why there was so much trouble with the Pint compared to other amps using jfet inputs. other than the fact 8397 likes to oscillate |
Originally Posted by Filburt ...yes. So are some of the other chips we've been looking at. Bipolar input isn't some sort of unmanageable thing |
Originally Posted by quicksilver96 I wasn't saying that it was unmanageable, just that the circuit topology so far hasn't been promising with the other bipolar opamp that had been tried (LM617x). I enjoy the sound of the LM617x and once I get around to working on this project, I will try a few things to get that offset down. If I can't, well theres plenty of JFET input chips that I'd stick in there too. I've also got a dual 8397 pint that runs without any problems. |