Reply
 
Thread Tools Display Modes
  #1   Report Post  
Posted to rec.audio.tech
Malfist Malfist is offline
external usenet poster
 
Posts: 5
Default Question about using more than one amp

Okay, I'm a newbie when it comes to speakers and that kinda stuff. As
of a few days ago I had a fully working Logitech X-540 speaker system
for my computer. Not the loudest in the dorm, but able to contend with
them. Then my subwoofer went out. Logitech, being the great company
that they are offered me a full replacement if I sent them the wired
control module (set won't work without it).

So.
I have a fully fuctioning new set in the mail, destined to arive
sometime soon, and the old set with 5 fully functioning speakers (5 of
6, minus sub). I'm going to buy spliters so I can hook both sets up
(10 satellites, 1 sub). The problem is power consumption. I know from
my digital electronics class that a system pulling nearly double it's
recommened power isn't good.

The subwoofer doubles as the amp/hub of the system so I don't think
it's replacable. Is there a way I can suplement it with another 120
watt amp? Or should I buy an amp that can handle both systems and a
new sub (because the sub doesn't have an output)?
  #2   Report Post  
Posted to rec.audio.tech
Dave Dave is offline
external usenet poster
 
Posts: 139
Default Question about using more than one amp


"Malfist" wrote in message
...

So.
I have a fully fuctioning new set in the mail, destined to arive
sometime soon, and the old set with 5 fully functioning speakers (5 of
6, minus sub). I'm going to buy spliters so I can hook both sets up
(10 satellites, 1 sub). The problem is power consumption. I know from
my digital electronics class that a system pulling nearly double it's
recommened power isn't good.

The subwoofer doubles as the amp/hub of the system so I don't think
it's replacable. Is there a way I can suplement it with another 120
watt amp? Or should I buy an amp that can handle both systems and a
new sub (because the sub doesn't have an output)?


Doubling the number of speakers, depending on how you wired them would
either a) halve the impedance, thus drawing double the current from the amp
and frying the output transistors in fairly short order or b) double the
impedance, resulting in crappy underpowered sound.

You MAY get away with it wiring the speakers in parallel pairs for 4-ohm
loads if you don't put the volume past 50%. I think the logitech amp is
probably a Class D or marginal AB piece of **** designed to operate at 99%
of it's theoretical maximum, said operating point carefully calculated by
their marketing department to give 366 days (one year plus a day) of
trouble-free operation to the average user (not a college student blaring
music at full volume) thus getting them out of the warranty period. For the
"rear channels" they simply incorporate a delay to give the IMPRESSION of
more than two channels. You'd be better off buying one of the many Velodyne
subwoofer plate amps that come up for sale on eBay for $30-$100 and
replacing the logitech gem. They'd have line-level inputs and a variable
frequency crossover for your satellites built-in to the amp. the downside
is that they generally only drive two satellite channels, BUT they may
provide enough power down to 4 ohms or even lower to cause your plastic
speakers to spontaneously combust.

I likely sound jaded, but I've worked on enough of this type of equipment to
know that by and large it's disposable trash... cheap cheap cheap components
used to build around a design with no safety margins encased in ugly plastic
shudder.

Dave S.


Reply
Thread Tools
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
question about live shows (the band simple minds) and unrelated audio question GreenSlimer Tech 8 September 28th 04 05:07 AM
question about the band Simple Minds (and live show question) GreenSlimer Pro Audio 0 September 13th 04 01:25 AM


All times are GMT +1. The time now is 08:14 AM.

Powered by: vBulletin
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 AudioBanter.com.
The comments are property of their posters.
 

About Us

"It's about Audio and hi-fi"