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Recommend me low-voltage dynamic microphone preamp circuit?

Can anyone recommend me low-voltage dynamic microphone preamp circuit similar to this one for ECM ???

  • Hello Schertler,

    In case you have a My analog account you can check this link, the document discusses an application that uses OP484 as an integrated mic preamp and amplifier driver.

    As an alternative solution you can also look at the SSM2167, which is already an integrated microphone preamp. The devices power up from a single 3v supply with THDN at 0.2% at 1kHz.  kindly refer below for the datasheet of the device and I am also attaching the application note using Mems microphone integrated to SSM2166.

    Can you please share more on your intended application of the preamp, and if possible more specifics on your target design, like what is operating voltage, current consumption,  expected noise density.



  • Hi Joven,

    So many thanks for your prompt, kind and very interesting feedback and

    nice to meet you!

    Your e-mail addresses look strange but hopefully my reply is being

    delivered properly to one of the e-addresses.

    My name is Misha, I am steel-string acoustic guitar player living in

    Tbilisi, Republic of Georgia (former USSR), and I looking for the

    quality dynamic mic (low-impedance 100-200 Ohm) preamp circuits to

    build and have it installed in the body of the new acoustic guitar


    In other instruments I do use electret condenser mics (miniature

    Oktava) wired to the guitar's on-board B-Band preamp system which I

    will NOT have available for the new instrument, so I have to build it

    myself and install in the guitar. ECM mics are most commonly used for

    acoustic guitar pickup systems, but now, due to the potential

    characteristics and less-prone to feedback, I am experimenting with

    little dynamic mic capsules and really got some success; these are

    100-200 Ohm capsules taken from quality earphones and they really work

    as good microphones, however with lower sensitivity comparing to ECM

    mics ......   I got this idea from Swiss company Schertler who

    produces moving-coil pickup systems with the similar impedance of

    200-300 Ohm, I find this technology of mics and ear-phone capsules

    almost the same using magnets and coils, I am sure this will

    definitely work just great.....

    So I am searching for some little preamp (PRE-PREAMP would sound more

    equally!) section based on 1-2 transistors or one OP-amp and having

    low-voltage powering of 3-4.5V (for easier installation in the

    guitar's body), the major requirements are the following:

    1. To preamplify signal from 0.5-1 mV to 10-15 mV

    2. To be designed for low-impedance dynamic mic inputs

    3. To having minimal number of other semi-conductors in the circuit

    4. To be ready-to-go, all the way tested and completed requiring no

    more experimentation with nominals of other semi-conductors.....

    In similar situations (compactly mounted internally in the guitar),

    some manufacturers do use couple of FET transistors, do you think that

    transistors might be any better of Op-amps in regards or self-noise,

    distortion and amplification ??

    If the higher voltage of up to 9V might be considered as a must for

    better results, then I would move to that circuit options.

    Sorry for such a large letter but otherwise it would not have the

    situation described and covered fully.

    Thank you for your time and consideration!

    With kindest regards,