Re: DIY Audio thread, show you DIY audio 'equipment' (Amps, BT etc...)
 

Hi there.

I received the mini-amp-board yesterday and i've been testing it.
First thing i made was creating an external stereo system for my old n-gage. and it rocked! Tomorow i will post some photos.

My problem now is to create the lowpass filter. In the videos i posted before i was using the amp of a home-subwoofer, that includes a lowpass in it and the sound was what i wanted. But using this mini-amp the sound is like a normal speaker (as everybody guessed).

I created a lowpass of second order using this "tutorial" http://autosom.net/artigos/crossovers.htm but the resulting sound is the same.

Could someone say what are the best values for this setup (mini-amp, that mini-subwoofer) ?

Thanks in advance

Re: DIY Audio thread, show you DIY audio 'equipment' (Amps, BT etc...)
 

Just reconfigured my original external amp to make it a bit smaller.
The output now goes in a 4 pin jack thats "mounted" on the amp, so now only one wire sticks out (power)

Attachment 22074
Attachment 22075
Attachment 22076


I think if i get around to it tonight i will make a youtube video showing the difference in loudness e.g. N900 playing normally on full, and with the amp and these sony speakers i just got (i get a lot of "junk" from everywhere, gets any worse i will probably be on hoarders :D)

Re: DIY Audio thread, show you DIY audio 'equipment' (Amps, BT etc...)
 

Just shot a video, crappy video but you get the "picture", next one will be in a room/shed.....


N900 Micro AMP, powered from the N900 to small speakers

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Re: DIY Audio thread, show you DIY audio 'equipment' (Amps, BT etc...)
 

@dr_frost_dk;

http://talk.maemo.org/showpost.php?p...3&postcount=13

Can you just clarify what happened with the audio volume there? Because your system is very similar to what I built for my car (the one that has the slight crackle). I'm thinking of putting a VMA2016 10Wx2 in between the BT board and car head unit, to try to eliminate the crackle (and also increase the volume, as it's fairly quiet, despite the head unit having it's own amplifier).

Also, found this: http://www.ebay.com.au/itm/VMA2016-2...item4cfa16a086

Handy little mounted board. Any idea on the purpose of the capacitor?

Re: DIY Audio thread, show you DIY audio 'equipment' (Amps, BT etc...)
 

Every audio amplifier needs power and the more current available the more output from the amp is achieved, think of it as a reservoir of energy which used to supply current to the amplifier as and when demands are made of it.

Re: DIY Audio thread, show you DIY audio 'equipment' (Amps, BT etc...)
 

as abill_uk says.

But if you run these amps of good battery's in my experience you can omit the capacitor

Re: DIY Audio thread, show you DIY audio 'equipment' (Amps, BT etc...)
 

Untill you start running kilowatts ;) then you need BIG caps or a wagon load of batteries ;).

When i lived in the Netherlands we had competitions on how quick your car would bounce a guilder off the roof with pure vibration from the speakers and massive output audio amps ALL homemade ;).

A nice little amp will always perform better with a "reserviour".

The post from 5spdvl's problem about "crackling" was most certainly down to insufficeant decoupling caps.

Re: DIY Audio thread, show you DIY audio 'equipment' (Amps, BT etc...)
 

Well, naturally my system is running off a 12V DC car battery, as it's in my car. I'm going to buy a VMA2016, clean it all up a bit and see how that goes. :)

Re: DIY Audio thread, show you DIY audio 'equipment' (Amps, BT etc...)
 

Make sure you you solder everything up well with no dry joints etc because that is a sure way to get rid of static, make use of decoupling caps where ever you can.

Re: DIY Audio thread, show you DIY audio 'equipment' (Amps, BT etc...)
 

Well the problem with car audio is the noise and interference from the generator, thats why a BIG cap helps when putting an power amp in your can, that and the power delivery.

If the noise you hear changes when the RPM changes then it is generator related.