sa mga masters naitn jan, patulong naman po sa aking first built na tone control.
ito diagram nia"
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Problem: walang bass tone, tapos medyo malabo ung sound,parang may sumasagitsit na kasama. Pero pag tinouch ko ung R2-47K umo-ok ung tunog with 1-2 seconds tapos balik ulit sa pangit.
ano po kaya magandang gawin dito. sayang namna kc ung effort,time at money kung di maaus.
tnx po in advance. alam ko semple lang to sainu.
Another classic symptom of parasitic oscillation. This is usually layout related. We can help you further if you show your layout.
A quick fix that may work is to reduce the bandwidth of your transistor amps. This can be done by increasing the value of capacitor C2 and C12. You can try using 100pF-470pF.
Be reminded that you should use linear type potentiometer for VR1,VR2 and VR4. Linear type pots are denoted with 'B' suffix (e.g. 100KB, 5KB) VR3 should be audio tapered ( identified with 'A' suffix e.g. 100KA, 50KA).
Finally, using a single pot for VR4 is a bad idea. You can't get a stereo separation better than 30dB with a single pot because it will allow excessive crosstalk to bleed through each channel. Use a dual pot instead.