Using AD825 in audio pre-amplification

[hot_chmock]

Hi,

Anybody have experience by the use of this op-amp in audio pre amplification?

I check the net but could not find any interesting information.

Any information or link is welcome.

Thanks,

hc

:wink:

 

[zurben]

ad825 audio

Hi hot_chmock

audio preamp for what? and why AD825?
Audio preamp is not "one size fits all" circuit :
low-z mics (50-200 ohms) preamp are quite different from line or hi-z mics, so, to optimize noise ,frequency response performances etc ,you need to match at least what different sources couples as load.(eg. 10Kohms for low-z mics versus 1Mohms or more for piezo,single coil guitars pick-up,47Kohms for MM phono pick-up, less than 50 for MC and so on)
Usually, with low-z sources, if you don't want to consider to use x-formers, bipolar op-amp do the best, while fet imput op-amp works fine on hi-z sources,so, mics preamp front-end, have commonly 2or more transistor acting as transimpedance section, followed by op-amp,because there are on the market few and not exactly cheap op-amp that can be succcesfully used as mic preamp.(but good xformer are more expensive than best op-amp)
Analog Devices SSM series and AD797 ,That's op-amp,Jensen devices are very very good as low-z mic preamp,while for line amplification, low noise precision op-amp are a less rare thing.Op285,Ne5532 are example of low cost dual op-amp with one third of noise respect single AD825. (although single devices shows better noise performances than duals).
Filters works at line level, so,medium to high speed low noise op-amp are preferred.


Theory,app. notes and working circuit are available from the above brandname and following links:

**broken link removed**
http://www.thatcorp.com/

Wireless World collected many milestones and at least very interesting articles in the past on audio preamp circuit, from single stage to entire mixing consoles.

hope help
zurben

 

[shanren]

ad825 op amp

AD825 for audio amplifier or modify your CD?try ad827 also.if you use for pre audio amplifier,use a good positive and nagtive power ,high enough,low noise,big capacitor(low ESR).and you must use low noise accurate resistance.good luck!