Noob Questions...

[MrGeebs]

Hi Folks,

Please forgive my noobness, but I have no knowledge of the things you all do... so please be patient

I bought a new sound card, which has upgradeable OPAMPS.

This new sound card has a very low mic input level even with the +20db gain enabled.

The sound card supposedly has 2 OPAMPS for the mic input.

I was wondering if you guys could tell me if you think upgrading the OPAMPS might increase the mic level to a more acceptable setting?

The makers suggests using OPA2604AP, or OPA2134AP...

I honestly dont know which is better, nor can I even seem to find a place that would sell me just 5 or 6 of them...

So again folks, please tolerate my noob questions, and feel free to share any advice or experience you may have I will most certainly appreciate it

[Leolabs]

Low input level problem is related to OPAMP gain setting,not just the quality of the OPAMP itself.

[darkfenriz]

opamp's gain is defined by passive components, most often resistors. A change of one resistor will do the difference. Change opamp if you want lower noise and/or distortion.

[MrGeebs]

hey, thanks for replying

I wish to improve my mics input level, so will upgrading the OPAMP acheive this result?

I have no soldering skills, so cahnging stuff on the PCB is out of the question.

The manufacturer says you can improve the cards performance by upgrading the OPAMPS..

Can someone tell me what the difference is between the two I listed above? Is one manufacturer better than another?

Here is alink to the product if it helps...http://www.auzentech.com/products_xplosion.html

Thanks again...

[AndrewT]

Hi,
if you select your opamp carefully you should be able to improve both the noise and distortion performance.

You will need some data on your mic and on your circuit to be able to make that selection.

You cannot change the gain unless you are prepared to investigate the gain components around the opamp and change at least one of them.

[infinia]

Investigate your mic and connections (buy a new cheap mic to test $5) before trashing exp. sound card.

Most probably a software setting

microsoft panel> options>properties>recording>ok>microphone>advance d

try it let us know when its fixed.

[DRC]

Do you have the correct type / impedance microphone for you soundcard ?

For example, if you use a 600ohm microphone into a 47kohm input you will get a very low ouput.

[myhrrhleine]

Changing the op-amps will change sound quality, but not amplification of the op-amps.

The op-amps have an amplification of about a million times.
Most of it is thrown away in 'feedback' which makes the op-amp more linear.

Gain is set by the ratio of feedback resistor to the resistor to ground.

Typically 1+(R feedback/R ground)