I'm planning a pedal sized guitar amp based on the TPA3116 driven by a MI Crunchbox guitar pedal. I'm using one of these boards for the power amp:
TPA3116 D2 TPA3116DA DC 12V 24V 100W Mono Channel Digital Power Audio Amplifier Board-in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group
When I hook the pedal straight into the power amp board I get sound, and it's nice and loud. I can hear the potential, but the sound gets way to bassy. The crunchbox is usually a pretty trbley pedal, but when hooked up to the TPA3116 I need to turn the tone control all the way up, and I still feel I miss a little too much treble.
The pedal has an output impedance at around 1 Kohm, and the amp board has an input impedance of 10 Kohm. Ofcource, the pedal is made to see impedance a lot higher than this, and I suspect that is why I get a lot of treble loss. What is the best way to fix this? I can't change the input impedance on the power amp without affecting the gain of the amplifier, right? And since the output of the pedal is 1 Kohm, I don't really see how a buffer can make things better?
I run the pedal at 16 volts, and it gives out enough power to work as a preamp for the power amp.
Any Ideas to how I can make this combo work? I can already hear that it has a lot of potential.
TPA3116 D2 TPA3116DA DC 12V 24V 100W Mono Channel Digital Power Audio Amplifier Board-in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group
When I hook the pedal straight into the power amp board I get sound, and it's nice and loud. I can hear the potential, but the sound gets way to bassy. The crunchbox is usually a pretty trbley pedal, but when hooked up to the TPA3116 I need to turn the tone control all the way up, and I still feel I miss a little too much treble.
The pedal has an output impedance at around 1 Kohm, and the amp board has an input impedance of 10 Kohm. Ofcource, the pedal is made to see impedance a lot higher than this, and I suspect that is why I get a lot of treble loss. What is the best way to fix this? I can't change the input impedance on the power amp without affecting the gain of the amplifier, right? And since the output of the pedal is 1 Kohm, I don't really see how a buffer can make things better?
I run the pedal at 16 volts, and it gives out enough power to work as a preamp for the power amp.
Any Ideas to how I can make this combo work? I can already hear that it has a lot of potential.
Try to put a 47nF capacitor in series between the pedal output and the amplifier input. With 10K input impedance, it should form a high-pass filter with a cut-off frequency of some 400Hz.
^^^ this will help no doubt, but deeper problem is all Guitar amps are strongly treble boosted by design, that´s the way it is, and pedals in general are treble cut to avoid them being "buzzy", poor highs have not a chance ; your amp is not "bassy" because of impedance mismatching but because it lacks the necessary "Guitar EQ".
To boot, it´s a voltage source and Guitar speakers love current sources or at least mixed feedback with very low damping around 1 , which boosts resonance and highs and attenuate mids for a sharper sound.
And what speaker are you using?
Brand and model, please; if not "Guitar" type it will lack the typical 8-12 dB peak present around 2500Hz which gives them "Bite" and attack.
I just checked the schematic:
Notice it has no treble boost whatsoever and has TWO treble killing stages: the Tone control VR2-C8 and the added R8 - C9 net.
Just for testing lift one leg from C8 and C9 to put them out of circuit and try.
Remember to post speaker model here.
To boot, it´s a voltage source and Guitar speakers love current sources or at least mixed feedback with very low damping around 1 , which boosts resonance and highs and attenuate mids for a sharper sound.
And what speaker are you using?
Brand and model, please; if not "Guitar" type it will lack the typical 8-12 dB peak present around 2500Hz which gives them "Bite" and attack.
I just checked the schematic:
Notice it has no treble boost whatsoever and has TWO treble killing stages: the Tone control VR2-C8 and the added R8 - C9 net.
Just for testing lift one leg from C8 and C9 to put them out of circuit and try.
Remember to post speaker model here.
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