Plate amp that can do "2.1"?

[joekraska]

Hi,

I'm considering making my own computer speaker system. I have the Logitech Z-2300, and it lacks midrange. The Z-2300 is rated as 'best' by various and sundry (as far as computer speaker systems go), so. Make my own, it looks like.

The Logitech has an integrated amplified subwoofer with 2 L/R active speaker outs. I.e., it is a "2.1" amplifier.

I would like to replicate this setup. Is there some simple way to do it with Dayton or Bash plate amps? I can't tell looking at them. At least one of the Dayton's say that their L/R line outs aren't active unless the powered line-in's are occupied.

I'd like to A) avoid an external amp, B) avoid multiple amps.

It would be nice if I could dial in some kind of cross over, too...

So how does this get done?

Joe.

[richt@daytonaudio.com]

Dayton MCA2550D 2.1 Channel Class D Amplifier

That link should help.

[biff]

Madisound has this one - XO and level adjustable, should make a great set with the right drivers!

http://www.madisound.com/catalog/pro...roducts_id=369

[joekraska]

Thank you for your pointer to the Dayton 2.1 amp. I had Googled for "plate amplifier" before and not found it, because it forwards me to your subwoofer amp page.

Be that as it may. How about something with more oomf? The subwoofer enclosure I'm intending will likely be a sealed or a sealed-passive-radiator design. These want some juice. I'd probably be happy in the 300 + 100/100w range...

I understand that there may not be such a part, but one can hope. :-)

Joe.

[fbov]

I don't believe there is such a part. You've found 2 very different sources for 2.1 plate amps which have the same power specs, 50W + 2x15W. I suspect that no one sees a market for higher power 2.1 plate amps given sub amps are cheap and stereo amps plentiful. Plus, give up a little extension and 50W can do some serious noise!
Frank

[joekraska]

Thank you for your reply.

The Logitech amp claims to be 120W +40W/40W. It's a plate amp. Presumably someone makes it. :-)

I could try this for the time being: replace the logitech satellites with full range speakers, and see how it goes?

Joe.

[djg]

Different kind of amps, probably, but I could be wrong.

[johnnyrichards]

Thank you for your reply.

The Logitech amp claims to be 120W +40W/40W. It's a plate amp. Presumably someone makes it. :-)

I could try this for the time being: replace the logitech satellites with full range speakers, and see how it goes?

Joe.

You might be disappointed even then... Logitech highpasses the satellite at ~180 Hz.

Best bet is to buy a plate amp for the bass and find a small (50wx2) stereo amp for the high end. I use an AudioSource Amp100 and it works pretty good for my PC setup.

[joekraska]

180!?!? Doh. That screws up that plan. That's leaving out a lot of the midbass...

Joe.

[Tony Nelson]

Is there a way to bipass or change the stock logitech high pass setting? I have the z-5500 and was thinking of doing it if I can.

[johnnyrichards]

Is there a way to bipass or change the stock logitech high pass setting? I have the z-5500 and was thinking of doing it if I can.

I'm sure there must be, but I have no idea how to do it...

The Logitech stuff has decent resale on the eBay.

[Mayhem13]

You haven't put a budget on this Joe as what you're attempting or intending can get kinda expensive for the level of simplicity you desire.....clearly all integrated amplification.

Honestly by the time you purchase a seperate sub amp, sat amp(s) and drivers you're outside of the fiscal benefits of DIY in my opinion. I'd stick with building the sub, but look towards active nearfield monitors for L/R duties.

Consider a pair of these http://pro-audio.musiciansfriend.com...ors?sku=600682 with a diy sub that has RCA level in/outs for pass through. After sub components not very cheap at all but as cheap as a project like this with integration is gonna be.

[joekraska]

Well. I was considering building the sub with a Boston subwoofer and a Bash 300 watt integrated amp. Maybe. I started hunting around to see if there was something big that could do 3 channel, or if there was something I didn't understand about 2 wire outs that would let me wire 3 speakers (I reasoned you couldn't do this, but was checking to make sure I wasn't wrong... actually I suppose I could do this, but I wouldn't have stereo--not good).

One of the Ampsource 100's or some similar variant would be okay. I've just been hunting around to see if I can get the satellites in one fell swoop on the amp.

I've been toying around with a the idea of a pair of Boston CS26's for the desktop satellites.

We're getting into the $500+ range there, although I'm still trolling around for creative ideas, and considering alternatives. Some of the components, like the CS26's, could become surround speakers for a later home audio system. As can the sub. So it's not as excessive as it sounds... :-)

Joe.

[joekraska]

I found a way to do this with a single amp, two satellites, and a sub. First you need a two way amp that is stable to 4ohm mono (not looking good). Anyway, with that in place, you can do a hybrid, 2 4 ohm satellites and 1 8 ohm subwoofer. The sub will get roughly half the power of the amp's output.

Joe.

[the kid]

Buy a good car amp & decent power supply. A lot of car amps are designed for what you are wanting to do.

[joekraska]

Define "decent power supply". High current 12v power supplies are relatively expensive. And large. I looked into this, because I have an old PPI car amp I am not using...

Joe.

[the kid]

Well, mostly one that will handle the amperage. I have been using a Rat Shack 3 amp supply & various car amps for a long time for my computer set up. I have had no problems handling the wattage. Though I have not played it hard or very loud for more than a few songs at a time. They sell a 10 amp version. Should do well.

My current set up is actually an Insignia receiver for the mains & a Soundstream 100 watt car amp for the sub. So far so good.

[joekraska]

3 * 12 = 36W. But the Soundstream is a 100W amp. Any thoughts on that math?

I did find a 15AMP 13.7V supply at RS for $85. That's 165W. Still not enough for my PPI competition AMP. Well. Theoretically. These car amps, I don't know what loads they *really* sustain. If it's peaks, I can always resort to the good ole' car amp trick of putting a big cap in line.

I suppose this could be an interesting experiment just for fun, though.

Joe.

[Wolf]

I found a way to do this with a single amp, two satellites, and a sub. First you need a two way amp that is stable to 4ohm mono (not looking good). Anyway, with that in place, you can do a hybrid, 2 4 ohm satellites and 1 8 ohm subwoofer. The sub will get roughly half the power of the amp's output.

Joe.

That's Tri-mode, and not all amps can do this. If you find one that can, you'll still need an outboard passive xover for the sub and sats.
Later,
Wolf

[the kid]

Buy this for the mains - http://www.parts-express.com/pe/show...number=252-100

connect the LFE sub out to this - http://www.parts-express.com/pe/show...number=300-805

Now you are up to date with some options and thingys to play with.