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Bargain WPC Speaker Upgrade £10 a pair for dual driver Sony xs-gt1328f
- Thread starter DRD
- Start date
Ok I bought the lpass filter listed here
http://www.ebay.co.uk/itm/400w-RMS-...ound_Vision_Speaker_Parts&hash=item540209b0b5
put it in my wh20 and it sounds ****e!
how can this effect the backbox speakers?
Do I need to get the Lpad too?
Thanks
http://www.ebay.co.uk/itm/400w-RMS-...ound_Vision_Speaker_Parts&hash=item540209b0b5
put it in my wh20 and it sounds ****e!
how can this effect the backbox speakers?
Do I need to get the Lpad too?
Thanks
B
backbox
hmm, this is trickier than it first seems!
If you kept the original wiring then putting the lpass in series with the cabinet speaker actually puts it in series with the backbox speakers as well, and so kills all mid and top frequencies.
So what you need to do is isolate the cabinet and backbox speakers by placing them in parallel, not series.
but ... original wiring has the two backbox speakers (2 x 4 ohms) in parallel = 2 ohms. These are then in series with the cabinet speaker (1 x 4 ohms) = total 6 ohms
If you simply put the cabinet in parallel, you'd now have 2 ohms in parallel with 4 ohms = 1.3 ohms = too low for the amp = distortion and possible amp damage.
If you rewire the backbox speakers in series = 8 ohms and then parallel the cabinet speaker, you'd have 2.7 ohms = probably ok.
also, this arrangement would more than double the output power from both the backbox and the cabinet speakers for a given input voltage.
Finally you could fit the lpass in series with the cabinet speaker without any effect on the backbox.
The Lpad will have no effect other than as a volume control (it would increase the impedance seen by the amp but wouldn't improve sound quality)
Ideally, you would do the above but replace the cabinet speaker with an 8 ohm woofer. This would raise the overall impedance to 4 ohms. Then you could fit the Lpad in series with the backbox speakers to act as a balance control between backbox and cabinet. (I wouldn't bother with the lpass!)
phew!
Rob
If you kept the original wiring then putting the lpass in series with the cabinet speaker actually puts it in series with the backbox speakers as well, and so kills all mid and top frequencies.
So what you need to do is isolate the cabinet and backbox speakers by placing them in parallel, not series.
but ... original wiring has the two backbox speakers (2 x 4 ohms) in parallel = 2 ohms. These are then in series with the cabinet speaker (1 x 4 ohms) = total 6 ohms
If you simply put the cabinet in parallel, you'd now have 2 ohms in parallel with 4 ohms = 1.3 ohms = too low for the amp = distortion and possible amp damage.
If you rewire the backbox speakers in series = 8 ohms and then parallel the cabinet speaker, you'd have 2.7 ohms = probably ok.
also, this arrangement would more than double the output power from both the backbox and the cabinet speakers for a given input voltage.
Finally you could fit the lpass in series with the cabinet speaker without any effect on the backbox.
The Lpad will have no effect other than as a volume control (it would increase the impedance seen by the amp but wouldn't improve sound quality)
Ideally, you would do the above but replace the cabinet speaker with an 8 ohm woofer. This would raise the overall impedance to 4 ohms. Then you could fit the Lpad in series with the backbox speakers to act as a balance control between backbox and cabinet. (I wouldn't bother with the lpass!)
phew!
Rob
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I grabbed a set of these just on the off chance they might have been of use.
Turns out though that they're too big for the DE tables so really not likely to be much use to me.
Anyone want them? Happy to accept what I paid for them plus postage.
Turns out though that they're too big for the DE tables so really not likely to be much use to me.
Anyone want them? Happy to accept what I paid for them plus postage.
Oh yes please!
Drop me a PM mate and we'll get something sorted.
I paid £10 for them. Not sure what the postage will be but can get a price when i'm back in the office and let you know.
Unfortunately I fly out of the country tomorrow and won't be back until next weekend, but I should be able to get them packed and shipped for you w/c 20th April.
I paid £10 for them. Not sure what the postage will be but can get a price when i'm back in the office and let you know.
Unfortunately I fly out of the country tomorrow and won't be back until next weekend, but I should be able to get them packed and shipped for you w/c 20th April.
I fitted a set to my G&R although it wasn't a 10 minute job and the back panel needed to be completely stripped and cut. They do make a difference to the sound quality though
Bet you're glad they have made an improvement.
Would have been a killer if after all that work there was no difference.
I'll look into alternative replacement speaker which are a closer size match for the R&B when I get further down the line.
Right now it's in pieces and it's not likely to be back together for a good few weeks (or maybe months) yet. I'll pass these speakers on for now.
Right now it's in pieces and it's not likely to be back together for a good few weeks (or maybe months) yet. I'll pass these speakers on for now.
OK, so here goes with the resurrection thread of the year so far.
Nearly 9 years old.
I'm currently fitting a pair of these speakers into Pharos' Fish Tales.
When fitting the right hand side speaker, do you remove the capacitor or keep it in series with the new speaker?
BTW what is it for?
Thanks
Nearly 9 years old.
I'm currently fitting a pair of these speakers into Pharos' Fish Tales.
When fitting the right hand side speaker, do you remove the capacitor or keep it in series with the new speaker?
BTW what is it for?
Thanks
That capacitor works as a high pass filter.
The speaker there is a tweeter for high end.
The only thing I would watch on older WPC games, is that most car speakers are 4 ohm. Put two in parallel - and that takes it down to 2 ohm. Which is not far off from a dead short and not good for the amplifer.
Early WPC have the cabinet speaker in series with the backbox speakers.
Later WPC games with the DCS sound has two outputs.
Always keep an eye on the impedance.
The speaker there is a tweeter for high end.
The only thing I would watch on older WPC games, is that most car speakers are 4 ohm. Put two in parallel - and that takes it down to 2 ohm. Which is not far off from a dead short and not good for the amplifer.
Early WPC have the cabinet speaker in series with the backbox speakers.
Later WPC games with the DCS sound has two outputs.
Always keep an eye on the impedance.
Thanks Phil