I'm on a quest to build a budget guitar amp from a broken bose SoundDock. I'm not new to electronic circuits, but definitely new to this level of electronics, I just work on guitars. Help and advice would really be appreciated.
Here's a comprehensive view of what i'm working with. I care mostly about the two 36W (or are they 18W or 10W? i'm a bit confused) speakers.
http://www.whatsinside.info/bose-sounddock-series-ii-internals/
project with same speakers, useful info - https://www.diyaudio.com/forums/pa-systems/336139-diy-column-speaker-pa.html
I have two potential approaches i'm thinking of:
app.1. Use the original pre-amp/amp circuit boards of the sounddock, and somehow install a mono guitar jack and power supply. Not sure if it's possible to instal gain,tone,volume controls with this approach, and how/where to wire mono guitar plug input.
if this is more easy than i imagine, it would be cheaper and i would have an amp sooner.
app.2. use this (or simmilar) amplifier circuit (https://www.anodas.lt/en/1x35w-tda8932-digital-amplifier-board), it matches both speaker power and impedance, with clear input, output, power terminals. I could install additional simple circuits for tone,volume, gain, maybe simple effect circuits.
question 1 - do i need an additional pre-amp circuit? i assume i do, due to the guitar pickup output impedance being in the kohm range.
__________ based on this previous advice i've gotten, i need a preamp circuit with the specs listed?______
1) The electrical signal from a guitar pickup is very weak, about 100mV.
The impedance of the pickup is generally very high, about 100kΩ. The purpose of the preamp is to present a high input impedance, about 1MΩ and output a much lower impedance of about 1kΩ. Also the preamp will boost the signal to about 1V.
2) The amplifier needs to take the 1V signal and boost both the voltage and current in order to drive a speaker with 8Ω impedance. For this the amplifier must deliver power.
___________
question 2 - would i need two separate amp circuits, for each of the two speakers individually? is it easy to split the signal from one pre-amp circuit to two amp circuits?
So, my current idea is this = mono-jack plug ---- pre-amp board ---- 2x(35Wamp board + 24V 2A dc power supply ---- bose speaker)
question 3 - am i completely R-worded, or am i looking in the right direction with this approach?
Here's a comprehensive view of what i'm working with. I care mostly about the two 36W (or are they 18W or 10W? i'm a bit confused) speakers.
http://www.whatsinside.info/bose-sounddock-series-ii-internals/
project with same speakers, useful info - https://www.diyaudio.com/forums/pa-systems/336139-diy-column-speaker-pa.html
I have two potential approaches i'm thinking of:
app.1. Use the original pre-amp/amp circuit boards of the sounddock, and somehow install a mono guitar jack and power supply. Not sure if it's possible to instal gain,tone,volume controls with this approach, and how/where to wire mono guitar plug input.
if this is more easy than i imagine, it would be cheaper and i would have an amp sooner.
app.2. use this (or simmilar) amplifier circuit (https://www.anodas.lt/en/1x35w-tda8932-digital-amplifier-board), it matches both speaker power and impedance, with clear input, output, power terminals. I could install additional simple circuits for tone,volume, gain, maybe simple effect circuits.
question 1 - do i need an additional pre-amp circuit? i assume i do, due to the guitar pickup output impedance being in the kohm range.
__________ based on this previous advice i've gotten, i need a preamp circuit with the specs listed?______
1) The electrical signal from a guitar pickup is very weak, about 100mV.
The impedance of the pickup is generally very high, about 100kΩ. The purpose of the preamp is to present a high input impedance, about 1MΩ and output a much lower impedance of about 1kΩ. Also the preamp will boost the signal to about 1V.
2) The amplifier needs to take the 1V signal and boost both the voltage and current in order to drive a speaker with 8Ω impedance. For this the amplifier must deliver power.
___________
question 2 - would i need two separate amp circuits, for each of the two speakers individually? is it easy to split the signal from one pre-amp circuit to two amp circuits?
So, my current idea is this = mono-jack plug ---- pre-amp board ---- 2x(35Wamp board + 24V 2A dc power supply ---- bose speaker)
question 3 - am i completely R-worded, or am i looking in the right direction with this approach?