Computer Hope

Hardware => Hardware => Topic started by: shaan94 on July 18, 2009, 05:35:06 PM

Title: Computer speaker
Post by: shaan94 on July 18, 2009, 05:35:06 PM
hi,

I've got a set of 5.1 speakers running on my pc, but the subwoofer is a bit rubbish. Heres a link to the speakers i have.

https://www.dixons.co.uk/martprd/product/seo/Computing/Communication+Solutions/Speakers/PC+Line/PCL-51001/619346


I also have a subwoofer from a DVD system lying around downstairs, so i was wondering if there is any way of connecting it to the pc speaker system to replace the rubbish one?

any help would be highly appreciated, thank you ;)
Title: Re: Computer speaker
Post by: fat_basterd21 on July 18, 2009, 06:01:53 PM
Cut and splice if needed. Only problem I see is the computer speakers not having enough power to run the sub. An alternative would be to replace the speaker in the rubbish one. Usualy you can buy them at raido shack ect..
Title: Re: Computer speaker
Post by: truenorth on July 18, 2009, 06:43:29 PM
shaan94, If your 5:1 speakers are powered which i feel very certain they are and if your audio controls can adjust the various qualities of the 5 speakers. Again given that your sound card can utilize the 5:1 speaker set up i suspect that it can. You may be able to compensate and get relatively better sound than the speaker you are now using. I would say try it and see. You really cannot hurt anything but as the previous poster advices you will probably need to modify the plug for the speaker jack output on the speaker cable. goodluck,truenorth
Title: Re: Computer speaker
Post by: shaan94 on July 19, 2009, 07:17:41 AM
Thank you very much for your help fatbasterd21 and truenorth :)

the 5.1 system is powered, but the power cable runs from the current sub (the rubbish one), so if i take that off there wont be a power supply.

Title: Re: Computer speaker
Post by: truenorth on July 19, 2009, 12:38:04 PM
Ouch--but not necessarily a limitation. You could by opening up the sub woofer enclosure (if you can) remove the internal connections that goes to only the subwoofer speaker and solder the replacement sub woofer in it's place. truenorth
Title: Re: Computer speaker
Post by: computeruler on July 19, 2009, 12:42:42 PM
So all the wires from the speaker goes into the sub?  Is the other sub from the dvd system the same way?
Title: Re: Computer speaker
Post by: fat_basterd21 on July 19, 2009, 11:09:53 PM
I agree with trunorth. Your going to want to open both up and try swapping out the speakers. But it still may not work. Impedance and wattage can be different. But I doubt the computer speakers have more wattage than a sterio speaker.
Title: Re: Computer speaker
Post by: lectrocrew on July 19, 2009, 11:21:18 PM
Impedance and wattage can be different. But I doubt the computer speakers have more wattage than a sterio speaker.
This is correct.
The main thing you dont want to do is to replace the current speaker with one of higher impedimence.
2 Ohms resistance speakers will over tax a system with a lower impedimence of 4 ohms or 8 ohms. If your current speaker is 8 ohm, do not install a speaker with a higher 4 or 2 ohm rating.
Title: Re: Computer speaker
Post by: truenorth on July 20, 2009, 07:34:38 AM
yes i too was somewhat concerned with the aspect of impedance but thought that with the newer technologies in both stereos and computers this might be less likely.truenorth
P.S. While it is not my field of expertise is it not also possible that if the impedance is too high it could be reduced? Then i guess it becomes a question of how far one wants to go just to try and use another subwoofer that is on hand?
Title: Re: Computer speaker
Post by: computeruler on July 20, 2009, 10:54:30 AM
Did anyone else think it might not fit either?  Anyways, when you take the speaker out it usually says the ohms.  It is ok to replace the speaker with something of a higher impedance, but the wattage will be reduced, thus not as loud.
Title: Re: Computer speaker
Post by: truenorth on July 20, 2009, 11:42:40 AM
Computeruler, Yes essentially that was the point i was trying to make at the outset--that because of the 5:1 ability of his existing sound card that the variables of the controls with the associated software would possibly make compensations effective to offset the wattage limitations. I guess we will only get to know if the O.P. actually goes ahead and tries it and tells us the result.truenorth
Title: Re: Computer speaker
Post by: fat_basterd21 on July 20, 2009, 12:31:29 PM
Provided it will fit theres probably 99% chance of it working. However the quality and life of the speaker will be determined by it being the proper speaker.
Title: Re: Computer speaker
Post by: lectrocrew on July 20, 2009, 06:43:55 PM
yes i too was somewhat concerned with the aspect of impedance but thought that with the newer technologies in both stereos and computers this might be less likely.truenorth
P.S. While it is not my field of expertise is it not also possible that if the impedance is too high it could be reduced? Then i guess it becomes a question of how far one wants to go just to try and use another subwoofer that is on hand?
I'm not aware of any technology that adjust automatically, (this may be available), although some systems that run 4 ohm (for instance) are 2 ohm stable systems that can handle the increased resistance in that case.
 A resistance load can be increased simply by wiring 2 speakers of lower impedimence either in series or in parallel, (there is a formula for determining the load in these cases), or adding a resistor into the circuit, but I know of no way to decrease the ohm rating of a speaker without modifying the vioce coil which takes advanced equipment or a person who is experienced in speaker building.
Title: Re: Computer speaker
Post by: lectrocrew on July 20, 2009, 07:46:31 PM
Did anyone else think it might not fit either?  Anyways, when you take the speaker out it usually says the ohms.  It is ok to replace the speaker with something of a higher impedance, but the wattage will be reduced, thus not as loud.
I may be wrong but I disagree. What happens with any circuit when introduce to a '0' ohm load? (just for example)
The wattage increases to whatever is the maximum wattage available in the supply circuit. Unless the circuit is fused lower than this load, the circuit shorts to ground and is no longer healthy.
I'll post a chart for ohms law pertaining to DC (direct current) voltage which is used in most speaker systems.

AMPS= WATTS÷VOLTS I = P ÷ E  A = W ÷ V 
WATTS= VOLTS x AMPS P = E x I W = V x A
VOLTS= WATTS ÷ AMPS E = P ÷ I V = W ÷ A
HORSEPOWER= (V x A x EFF)÷746
EFFICIENCY= (746 x HP)÷(V x A)

Here's the key chart for those symbols


E =VOLTS ~or~ (V = VOLTS)
P =WATTS ~or~ (W = WATTS)
R = OHMS ~or~ (R = RESISTANCE)
I =AMPERES ~or~ (A = AMPERES)
HP = HORSEPOWER
PF = POWER FACTOR
kW = KILOWATTS
kWh = KILOWATT HOUR
VA = VOLT-AMPERES
kVA = KILOVOLT-AMPERES
C = CAPACITANCE
EFF = EFFICIENCY (expressed as a decimal)

Yes i've run higher impedimence speakers on several sound systems that were not stable operating as such, but the sound is muddy and the system is overworked. And some of them didn't survive. I'd try it on my 9 year old EMachines but not on my $1500 quad core build. JMO
Title: Re: Computer speaker
Post by: computeruler on July 21, 2009, 10:27:11 AM
Its not good to run a 2 ohm speaker on a 4 ohm amp or something.  The amp expects a higher resistance and dies