DIY Amp Combo

[brianstarcore]

Hello! I'm new in this forum, I was looking through internet and forums about some technical questions but I see that in this forum are some people with big understanding about amplifiers.

I'm an Electric engineering student and i'm looking to do an Amp combo for a project or maybe the tesis (capstone). Amp Combos are pretty common right now, so there's nothing new, maybe one thing. I want it like an all in one audio equipment and also use it for me (I also make music). So the features:

- hi-fi sound (close to it, good sound)
- Guitar Cab
- Bass Cab.
- Vocals Cab.
- General Music Cab.
- 300W power or near it.

- like $500 price. I dont want a $1000 equipment

The formula: using two speakers one bass speaker (woofer) and one guitar speaker (mids) also some tweeters. Like a home audio equipment that have speakers enclosures with 3 speakers.

I need to do it almost from scratch for the capstone but I will going to buy the boards like an power amp board and then reverse-engineering it so I will know how they do the board. Anyway the questions is:

Power amp Board: I was looking a china 300W solid state board that looks nice on ebay. Someone in this forum bought it like in 2012. I think that with the best cooling and power it will work nice. Still I dont know if it needs an preamp. I will buy a simple small mixer with 4 inputs and eq so the output of it will go into the power amp. IDK if I need a preamp in the middle. Speakers I will go with celestion and maybe Jensen. I will put a crossover in each of them.

This is the power amp in question:
LME49810 Top Audio High Power Amplifier Kit Board Mono 300W 2SA1943 2SC5200 | eBay

Thanks!

 

[indianajo]

The reason people build separate guitar amps, and PA (general music) amps, is that guitar sounds better with a limited frequency amp. High frequency response on a guitar amp just transmits the squeaks of the fingers moving around on the strings.
Vocals sound better with the bass filtered out, since most of the bass in a vocal pickup is the pounding of the feet of the band on the floor of the stage.
Plus gigging with a band, carrying around all those speakers and crossovers for frequencies that the instrument doesn't need, makes setting up harder on the band. Especially in the beginning when roadies are volunteer and usually unreliable.
The amp module may be fine, but it appears to be missing heat sinks. Paying separate freight for those is a PIT* if you can even find anything suitable. My usual suppliers here in the US are *****y at supplying amp heatsinks. Small suppliers often have a deal where UPS charges are double or triple what a major supplier charges. I put off buying a mike for a year because the Ebay listing supplier wanted $78 for UPS freight from CA to IN. Didn't happen.
Best of luck.

 

[brianstarcore]

Thanks!, I will to look on that, Im thinking that each channel (input) have its own Equalizer still I have like an year and half to make this and check errors.

Searching I think that this will resolve my problems:
3-way Speaker Frequency Divider Crossover

Is very rough to say that this will works fine but it says

Total Power: 280W (Power ratio: Bass 65%,Mediant 20%,Treble 16%)

So a little math:

bass: 182W max
Meds: 56W max
highs: 44.8W max

my bass speaker is like 150W so I need roughly 56W guitar speaker and 44.8W tweeters.

I dont know if this will give to me a flat response. I hope...