Speakers using a modified sine wave inverter

**frostband** · 05-04-2004, 03:25 PM

I was thinking about using an inverter to power both my computer and some Logitech z560 (or z680) speakers. A 400W system for a car is usually really expensive, so I though I could just set up the Logitech speakers and have a nice surround sound system for cheap.
Is there a problem running speakers off a modified sine wave? Has anyone actually tested it?

The thought was using a MEGA 160 PC from MSI (barebones PC, nice small case that I could take out of the car for LAN parties possibly?), AMD Barton 2500+, 160GB HD, 512mb, DVD/CDRW, and the Logitechs and hooking all that up to an inverter of 600W, 800W, or possibly 400W if I don't turn the speakers up loud, but I think I'd rather just go with a 600W or higher inverter.

Any thoughts?

**no1knows** · 05-04-2004, 03:28 PM

Your speakers are more likely to take DC input themselves, wot you'll be doing is going DC 13.8V - AC 240V - DC 15V (or wotever yr speakers are). Yo might be better off getting a DC-DC converter, those Sin wave invertors are pretty pricey.

But if yr set on the inverter i cant see a problem, modified sin waves are as close to mains AC you can get.

**wyckyd** · 05-04-2004, 04:25 PM

why are you using computer speakers in your car? Don't you have regular car speakers?

**frostband** · 05-04-2004, 05:50 PM

Originally Posted by wyckyd

why are you using computer speakers in your car? Don't you have regular car speakers?

Yes, I have stock car speakers. But I would rather have a nice quality set up (the Logitechs are definitely quality). The Logitech z560 setup is 400W for around $100 (ebay). If I tried to get a 400W quality setup of car audio, it would cost me around $500 or possibly more.

Originally Posted by no1knows

Your speakers are more likely to take DC input themselves, wot you'll be doing is going DC 13.8V - AC 240V - DC 15V (or wotever yr speakers are). Yo might be better off getting a DC-DC converter, those Sin wave invertors are pretty pricey.

But if yr set on the inverter i cant see a problem, modified sin waves are as close to mains AC you can get.

These Logitechs are good computer speakers and they plug into an AC outlet in the wall (or the inverter in the car). I don't think I could hook them up to a DC-DC converter. Also, even if I figured out a way to do it, I haven't seen a DC-DC converter that can do even 400W (probably because I haven't searched for one). If there is one that does 400W or greater, I'm sure it would cost me more than a pure sine wave inverter.

My question is, would it be alright to use these speakers with a modified sine wave inverter instead of a pure sine wave (purely for economical reasons)?

**no1knows** · 05-04-2004, 05:54 PM

Frostband, you can get a much better car audio setup for the price your looking at, i doubt a modified sine wave would work too well, even if it did, the speakers your talking about werent designed for automotive applications. Go buy a cheap 4 chan amp and upgrade yr stock speakers, far better option and u could probably do it for under $150.

**frostband** · 05-04-2004, 06:03 PM

I seriously doubt you can get a car audio setup that's QUALITY for under $150
Including 4 speakers and a subwoofer. The Logitechs are high quality and they come with everyone on them, amp, sub, speakers etc...
A cheap 4 chan amp is NOT quality; it probably produces some noise or artifacts because it is cheap. As for speakers, you can get 4 high quality speakers for $150 not including a sub or amp.
As I have said, the Logitechs are high quality (rivaling Klipsch and Pioneer) speakers, sub, and amp all for around $100 (and I already have some on my computer that I could test in the car, only if I could find someone with a 200W or higher inverter to test them with).

I apprecieate your thoughts, no1knows
But I'm trying to find someone with experience in testing computer speakers with a modified sine wave inverter.

**no1knows** · 05-04-2004, 06:29 PM

dear o dear, ok. I'll leave ya to it.

**parawing742** · 05-04-2004, 06:36 PM

eBay is your friend. I recently purchased 4 100watt COMPONENT speakers for my truck for just $25/piece. They were last years model and are now discontinued, but they sound great.

**toadster123** · 05-04-2004, 06:47 PM

yea i dont really know how you would mount the computer speakers anyways....

i have never heard of anyone doing this before, so u might just have to go out and by an inverter and just test it.... i know u can get 400watt inverters for like $30... (not pure sign wave of course)... so i doubt a higher wattage inverter would cost that much more... (unless u wanted a pure sign wave... [am i spelling that right?])

**Zac** · 05-04-2004, 08:43 PM

i can go test if you'd like but ill just leave it at that it'll work...your speakers's amp probally runs off of 15v DC (easiest way is to look for a huge brick attached to your power cord...thats it :P)
(my computer speakers's transformer takes 120v AC @ .6A ...so 72 watts)

like everyone else mentioned though.....i still think you would get better sound by upgrading your car speakers. since theres a bit of competition in this area, cheap and good speakers are easy to pick up.

but if you dont have the cash then go ahead with this idea...just dont be surprised when your awesome computer speakers dont seem as great in your car.

and toadster: its "sine"