TL074 Bass Extender Circuit

Bass Extender – Circuit consists of an opamp (TL074) and a few passive elements (resistor capacitor) supply voltage is 12..20 volts DC.. It is used to amplify bass sounds. The pcb drawing is very elegant, and the capacitors specified as NP in the low-cost bass booster circuit are electrolytic. type but will be non-polar RS resistor 56k also it would be better if all resistors used in the circuit have 1% tolerance

Author’s explanation: At +3dB amplitude at 70Hz, if we apply bass sealing (for a closed enclosure), which increases to a maximum increase of about 11dB or more, it partially compensates for the speaker’s roll, thereby increasing the bass response by one octave.

As we’ll see later, the Bass Extender can be designed for either type of enclosure, and less reinforcement can be applied to a ventilated enclosure than to a closed enclosure. This is the opposite of what you might expect, but necessary, because the speaker cone in a vented enclosure puts very little loading below the box resonance.

There is a limit to the amount of bass compensation we can apply though. A speaker’s cone excursion increases as frequency decreases, so large bass boost levels test the speaker’s mechanics and the enclosure’s damping ability. Also, some power amplifiers are likely to start clipping.

Circuit diagram

Source: http://www.siliconchip.com.au/cms/A_104168/article.html

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