Choosing an amp, attaching gain control and inputs.

[LastShadow]

First things first. This is my first post on htguide.com and I am incredibly happy to find a community that is so interested in DIY speakers. Thank you.

Unfortunately, I am new to the game. I have a good understanding of crossovers and am working on a speaker that will have an integrated amp. In order for this to work it will need to accept an RCA and have gain control. The problem is, I have no idea how to choose the right amp or where to integrate the aforementioned features. I am looking for an amp to accommodate 150 watts RMS. Also, can I use a sub amp? Why/Why not? I have a feeling this is a dumb question as they are probably designed to output a lower frequency range only.

LastShadow

[Thooms]

Usually in this situation you'd use a preamp for gain control and the power amps in the speakers will have a fixed gain - that way you don't have to constantly adjust both speakers to have the same volume.

Sub amps usually have an active crossover built in, so you wouldn't get anything above (say) 150Hz out because it'd be trimmed off by the filter. I'm not sure if you can get full range plate amps - but you could always make your own

Presumably it's a full range speaker? If there's just one that would make a preamp relatively pointless - you could try a potentiometer (and a simple opamp buffer if required) on the input of the amp if you find an otherwise suitable amplifier which doesn't have gain control.

[LastShadow]

Yes it is just a single full range speaker for music playback. It should accommodate 33Hz and up.

[LastShadow]

Can you be more specific as to how I could incorporate the RCA? I thought the potentiometer was a good idea after a quick look. As far as the amp goes... FML... not sure I am ready to build one.

[LastShadow]

To get an idea I want to do something very similar to this http://www.martinlogan.com/products/purity

[PanteraGSTK]

If you don't want to build the amps yourself you could always grab some recording monitors and steal their amps. The only thing is that most are bi-amped so you would need to keep that in mind.

[Undefinition]

There's a guy who did a version of the Overnight Sensations with a built-in amp. Might give you some ideas.

http://techtalk.parts-express.com/showthread.php?t=212169

[Thooms]

You'd ground the (-) terminals and then off you go!

For an amp, maybe one of these kits could be worth building? They're pretty straightforward - could be worth thinking about.

http://www.chipamp.com/lm3886.shtml

That said, amp building is pretty addictive...tread carefully

[heapatrouble]

Class D Kits

These kits have received good reviews and are configurable or sold with all the features you seek. It would be a relatively simple matter to install an amp in pretty much any kind of speaker with sufficient internal volume.

http://classdaudio.com/index.php/

In particular, check out the SDS amp kits as they come with gain controls and would be very easy to adapt to what you described.