Is this Setup Safe?

[Static]

I'm upgrading my PC's sound system. I have been using an old Klipsch

Promedia 4.1 computer setup--four sats wired to the sub, which has its

own amp for all the speakers. Specs here:

http://www.klipsch.com/products/det...omedia-4-1.aspx

I've since replaced the front sats with pair of Paradigm Mini Monitors

(v.1) and the rear sats with a pair of Paradigm Atoms (v.1)

Is it safe to do this? I've read about clipping and am worried I could

damage my speakers or the Klipsch amp if they are a mismatch ... I

don't crank the volume that loud but if I'm listening to the radio over

my PC I sometimes turn up the rear speakers so I can hear them in other

parts of the house.

Any advice would be most appreciated!

[DrWho]

You will be fine as long as you don't clip the amplifier - you might take the time to find out where this level on the volume knob is and never go above that point. A little clipping usually doesn't kill amps instantly, but you're on your own with that...

I think you would be far better off to invest in a receiver to power your Paradigms. I know that means more money, but it's the proper way to do things and will yield far far better sound quality. It also opens the door to future upgrades. I run Chorus II's as my computer speakers []

[Static]

DrWho - thanks so much for responding!

You will be fine as long as you don't clip the
amplifier - you might take the time to find out where this level on the
volume knob is and never go above that point. A little clipping usually
doesn't kill amps instantly, but you're on your own with that..

How do I know when I'm clipping the amplifier. Is there something I should listen for?

I
think you would be far better off to invest in a receiver to power your
Paradigms. I know that means more money, but it's the proper way to do
things and will yield far far better sound quality. It also opens the
door to future upgrades. I run Chorus II's as my computer speakers []

You're exactly right, and that is what I tried to do--I bought an old Denon receiver and hooked my speakers up to it and they sounded great ... but I was hoping to use the Klipsch promedia as the sub and it just won't work. I have a Creative xfi soundcard and I'm running a 4.1 setup. The xfi won't give me a separate bass channel unless I set it to 5.1, which leaves a big hole in the sound field. I thought I could connect the sub to the receiver and get bass that way, but I have my soundcard hooked up to the 6 CH EXT IN connection on the receiver and since I don't have a separate bass channel connected, I don't get much bass. I thought it would automatically send the bass from the front and rear channels to the sub out, but no--it won't. I thought maybe this was just a cheap receiver, but when I tried to do the same thing on my dedicated HT receiver (Denon 3802) the same thing happened--no bass in to the 6 CH EXT IN means no bass out, even with the speakers set to small ...

So if I want any bass at all, right now I have to run my speakers through the old Promedia sub instead of the receiver I just bought. Eventually I might get a sub with line levels in, meaning I could run my speakers from the receiver to the sub which would then filter out the bass from the bookshelves and output it ... (hopefully).

Thanks again for responding, DrWho! Sorry if I'm babbling but this problem has been driving me crazy ...

[DrWho]

Gotta love creative...

Which Denon model are you running? Does it have LR preouts? If you can

find a LR output on your receiver that changes with the volume dial

(perhaps a zone2 or recording feature?), then you can connect the input

to the promedia to these jacks. The internal crossover will then

automatically redirect bass below 150Hz (?) to the sub.

Another alternative would be to run the digital output from the

creative into a digital input on the receiver. This will allow you to

run the bass management inside the receiver and then all you need to do

is put the receiver into a dolby prologic mode to get all the speakers

working. I believe the creative cards have the ability to output a

dolby prologic signal too? which should then emulate surround sound for

things like games. For movies you'll have discrete surround sound just

like normal. I think a lot of modern games are encoded in dolby

prologic anyways...it's been a while since I've been into the gaming

scene. You can also experiment with the 5-channel stereo mode on the receiver too. All of these modes will properly redirect the center channel info as long as you tell the receiver that you have no center channel.

And lastly, your third alternative is to purchase a 5th speaker for true 5.1 []

[Static]

Gotta love creative..

Yes--they are terrible. But ever since Aureal went under, Creative has effectively had no more competition when it comes to surround sound for PC gaming. And that's the main thing I use my PC sound system for, although I sometimes listen to music and archived radio as well.

Which Denon model are you running? Does it have LR preouts? If you can
find a LR output on your receiver that changes with the volume dial
(perhaps a zone2 or recording feature?), then you can connect the input
to the promedia to these jacks. The internal crossover will then
automatically redirect bass below 150Hz (?) to the sub.

It's a Denon AVR-1400. I don't know what I was thinking when I bought it. It's ancient. Before Dolby Prologic II even. But it does have L, R, C and Sub pre outs (already tried the sub pre out). Just now I hooked up the front inputs from the Promedia to the receiver like you suggested----and it worked! I get bass for the front speakers! But ... isn't this the same as if I just ran the front speakers through the Promedia and eliminated the Denon receiver entirely? The receiver is taking the signals for the fronts from the xfi soundcard, and passing them directly to the amp in the Promedia. Isn't that the same as taking the Denon entirely out of the loop? And wouldn't I still run the risk of clipping with the Promedia? Please let me know your thoughts on this.

Another alternative would be to run the digital output from the
creative into a digital input on the receiver. This will allow you to
run the bass management inside the receiver and then all you need to do
is put the receiver into a dolby prologic mode to get all the speakers
working. I believe the creative cards have the ability to output a
dolby prologic signal too? which should then emulate surround sound for
things like games. For movies you'll have discrete surround sound just
like normal. I think a lot of modern games are encoded in dolby
prologic anyways...it's been a while since I've been into the gaming
scene.

Ah, I wish the AVR-1400 had digital input. In my sheer stupidity I figured I didn't need it, since I wasn't planning on running digital anyway (I should know to always preserve as many options as possible). For games, the digital would only pass a stereo channel, but then I could have used my receiver to convert that into Prologic ... if I had a digital input.

. You can also experiment with the 5-channel stereo mode on the
receiver too. All of these modes will properly redirect the center
channel info as long as you tell the receiver that you have no center
channel.

Hadn't thought of that. There is an option on the receiver to set the center as a phantom channel, but for some odd reason that option is ONLY available when running in Prologic mode ... I think the five channel stereo option takes a single stereo source and converts it into the five channels--but I would be running a quad source from the xfi, not stereo. I think the only way to hook up all four channels into the receiver is through the 6 CH EX IN ... which won't let me run in Prologic or set the center as a phantom ...

And lastly, your third alternative is to purchase a 5th speaker for true 5.1 []

Which would probably be the best option ... If I hadn't already backed myself into a corner. I just bought the two Paradigm Mini Monitors off ebay to use as my fronts ... There is no way a third would fit under my monitor--they're just too big. If I had stuck with the little Atoms it would have worked out great (sigh). I hadn't thought there was much advantage, game-wise, in going from a 4.1 to a 5.1 setup--but then I didn't know I was losing out on a dedicated sub channel on the xfi with 4.1 (Creative should just call it "4" since there is no .1)

Thanks again for all your help, DrWho! (Loved the original BBC TV show, by the way. I actually watched it as a kid back in the black and white days!)

[DrWho]

I too run Creative cards as they are the best for gaming so I know exactly where you're coming from.

Since your Denon actually has pre-outs, I'm gonna chime in on that configuration since it will be your most ideal (given the current equipment). Set your XFi to output 4.1 and run the signal into your multi-channel inputs and connect your mains/surrounds just like you originally had everything set up. Then connect your promedia to the LR preouts.

In this configuration, you're going to have the receiver power every speaker with its own amplifiers. This means that you'll have no speakers connected to the outputs on the back of your subwoofer. The crossover for the sub will actually be taken care of by the promedia control pod so all you have left to do is set the volume on the control pod to blend the sub in with the mains. Once set, you can tuck the control pod away and never have to worry about it (unless of course you wanna exagerate the bass for games and then turn it back down to flat for music).

I think that covers everything? And I hope it explained your question about clipping - it was a bit roundabout so let me know if you have any more questions.

Have you seen the latest new seasons of Doctor Who? I was actually quite surprised. I don't think I need to mention that I'm a huge fan []

[Static]

I too run Creative cards as they are the best for gaming so I know exactly where you're coming from.

Since your Denon actually has pre-outs, I'm gonna chime in on that configuration since it will be your most ideal (given the current equipment). Set your XFi to output 4.1 and run the signal into your multi-channel inputs and connect your mains/surrounds just like you originally had everything set up. Then connect your promedia to the LR preouts.

In this configuration, you're going to have the receiver power every speaker with its own amplifiers. This means that you'll have no speakers connected to the outputs on the back of your subwoofer. The crossover for the sub will actually be taken care of by the promedia control pod so all you have left to do is set the volume on the control pod to blend the sub in with the mains. Once set, you can tuck the control pod away and never have to worry about it (unless of course you wanna exagerate the bass for games and then turn it back down to flat for music).

I think that covers everything? And I hope it explained your question about clipping - it was a bit roundabout so let me know if you have any more questions.

Have you seen the latest new seasons of Doctor Who? I was actually quite surprised. I don't think I need to mention that I'm a huge fan []

I can't believe it. I've been posting on several different forums all day without getting any where, but I think you've actually solved my problem. I hooked it up just as you said and it worked! The Promedia control pod controls the bass, and the receiver does everything else!

How does this work, exactly? The Promedia is getting the left and right front signals, filtering out the mids and highs to the (nonexistent) satellites, and only playing the bass ... and the receiver is also sending the left and right front signals to the bookshelves? I thought pre outs sent the entire signal to an external amp?

However it works, I'm happy! The bass is a little boomy but I'm still tweaking it. I wonder if it's running through two crossovers, the receivers and the Promedias? Unfortunately I can't access either one--the manual for my ancient Denon doesn't even mention a crossover or any sub setting whatsover, and the Promedia crossover is fixed for the sats that came with it ...

Thanks, DrWho!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Haven't seen the show in years. I watched the old black and white episodes, and some of the color ones with the various actors playing Who, and some of the old movies (Dr. Who and the Daleks!). I'll have to check out the new show--is out on DVD?

Thanks again, Doctor! You solved this problem when no one else could.

[DrWho]

The receiver is sending the exact same full range signal out of the

pre-outs AND amplifier outputs. The reason only bass comes out of the

promedia sub has to do with the way the control pod filters the

signal...

The promedia control pod does a few things: It combines the LR signal

into a mono signal and then puts it through a low pass filter before it

gets sent to the internal subwoofer amp. The unfiltered LR signal

(still stereo - not mono) gets run through a high pass filter and then

sent to the internal amp. The amp will be creating a voltage at its

output terminals, but since no speaker is connected, no current is

going to flow and thus it doesn't supply any power to that amp.

The only problem that you're going to run into with this configuration

is the overlapping crossover region. Your Mini-monitors are good down

to 70Hz, so ideally you would have the crossover on the subwoofer set

to 70Hz to fill in where the mains roll off. However, the crossover in

the promedia control pod is set to 150Hz (to fill in where the promedia

sattellites roll off). So right now you've got an octave of sound being

reproduced by both speakers (70-150Hz) - This will increase the output

in that region and is likely to be percieved as boomy/muddy bass.

To remedy the overlap, you'll need to employ a filter to prevent

frequencies above 70Hz from passing through to the subwoofer. I think

something like this would be your best option:

http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=266-252

Just connect both plugs to your LR preouts. Basically it will send only

70Hz and below to the promedia control pod. As I mentioned above, this

signal will get summed to mono and then run through the 150Hz LPF.

Since the only frequency content present is 70Hz and blow, the LPF

really isn't going to have any effect. In the end, you end up with 70Hz

and below coming out of the subwoofer - which is what you want for

integrating the bass with your mains.

[Static]

The receiver is sending the exact same full range signal out of the
pre-outs AND amplifier outputs. The reason only bass comes out of the
promedia sub has to do with the way the control pod filters the
signal...



The promedia control pod does a few things: It combines the LR signal
into a mono signal and then puts it through a low pass filter before it
gets sent to the internal subwoofer amp. The unfiltered LR signal
(still stereo - not mono) gets run through a high pass filter and then
sent to the internal amp. The amp will be creating a voltage at its
output terminals, but since no speaker is connected, no current is
going to flow and thus it doesn't supply any power to that amp.



The only problem that you're going to run into with this configuration
is the overlapping crossover region. Your Mini-monitors are good down
to 70Hz, so ideally you would have the crossover on the subwoofer set
to 70Hz to fill in where the mains roll off. However, the crossover in
the promedia control pod is set to 150Hz (to fill in where the promedia
sattellites roll off). So right now you've got an octave of sound being
reproduced by both speakers (70-150Hz) - This will increase the output
in that region and is likely to be percieved as boomy/muddy bass.



To remedy the overlap, you'll need to employ a filter to prevent
frequencies above 70Hz from passing through to the subwoofer. I think
something like this would be your best option:

http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=266-252

Just connect both plugs to your LR preouts. Basically it will send only
70Hz and below to the promedia control pod. As I mentioned above, this
signal will get summed to mono and then run through the 150Hz LPF.
Since the only frequency content present is 70Hz and blow, the LPF
really isn't going to have any effect. In the end, you end up with 70Hz
and below coming out of the subwoofer - which is what you want for
integrating the bass with your mains.

Awesome. I thought I knew a little about audio but I'm a total ignoramus compared to you. I think I'll order that part, though I'll have a hell of a time explaining what it does to my wife ("I thought you weren't going to spend any more money on speaker stuff!")

One other slight problem with the current solution--bass is only matched with the front speakers, not the rear. There is an audible drop in bass from the rear speakers in gun battles and such. But it's still a huge improvement over no bass at all.

Did a search on the Creative forums and found out there are a lot of 4.1 people in my same situation, unhappy that the only way they can get their xfi to activate the sub channel is by selecting 5.1, with the resulting problem of the missing center channel ... One person posted a possible (but dangerous?) solution:

"You could actually redirect the centre channel through the line-in if
you are careful not to enable CMSS. With multi-channel sources, the
centre channel will be redirected only to the front left and right, but
with CMSS upmixing, part of the redirected signal will also be sent
back to the centre channel creating a feedback loop. There could be a
small delay in the redirected centre channel due to the loopback
through the line-in. It would also mean you're limited to using only
the front speakers with stereo sources."

I think the idea is to tell the card you have a 5.1 setup, then split the center/sub out from the card and curve the center back to the card's line in(!) which then gets mixed with the fronts while the sub line out can be directed to the sub ... but if you get a feedback loop you could potentially destroy your speakers. What do you think, Doctor? Would this potentially create more problems than it could solve?

[Arky]

Who to the rescue, na na na na...

[DrWho]

Hmmm...I didn't think about the rear channels. In that case, a perfect solution would involve running your soundcard in 5.1 and then implementing a 3-channel to 2-channel converter box that equally adds the center channel output to both the LR. This would then give you the option of running the bass management on your soundcard - in which case you wouldn't need the line-level LPF dohickeys. I think such a circuit would only need to be a few resistors wired carefully together - perhaps a pot to set the relative level of the center channel, but that can be done on the soundcard. It sounds like there is quite a market for such a device - I wonder how much it would end up costing...

I wouldn't mind putting one together if you were interested - if not, I won't worry about it.

[Static]

Hmmm...I didn't think about the rear channels. In that case, a perfect solution would involve running your soundcard in 5.1 and then implementing a 3-channel to 2-channel converter box that equally adds the center channel output to both the LR. This would then give you the option of running the bass management on your soundcard - in which case you wouldn't need the line-level LPF dohickeys. I think such a circuit would only need to be a few resistors wired carefully together - perhaps a pot to set the relative level of the center channel, but that can be done on the soundcard. It sounds like there is quite a market for such a device - I wonder how much it would end up costing...

I wouldn't mind putting one together if you were interested - if not, I won't worry about it.

Is that what I'd be doing if I connected the line in to the center/sub out--minus the threat of destroying my equipment via feedback? I might be interested in a converter, depending on the price. No idea what the range might be? Might be more worth your time if you had more than buyer. If you do a search for "4.1" on the Creative forum you'll find a bunch of threads from people looking for a solution:

http://forums.creative.com/creativelabs/board/message?board.id=soundblaster&message.id=63114&query.id=26434#M63114 (this one gets particularly heated)

http://forums.creative.com/creativelabs/board/message?board.id=soundblaster&message.id=31906&query.id=26434#M31906

http://forums.creative.com/creativelabs/board/message?board.id=soundblaster&message.id=33605&query.id=26434#M33605

http://forums.creative.com/creativelabs/board/message?board.id=soundblaster&message.id=71624&query.id=26434#M71624

http://forums.creative.com/creativelabs/board/message?board.id=soundblaster&message.id=33605&query.id=26434#M33605

http://forums.creative.com/creativelabs/board/message?board.id=soundblaster&message.id=34616&query.id=26452#M34616

EDIT: Not sure why the links I posted are disabled ...

I don't know how old some of those threads are, and some posts are from the same handful of people, of course. I revived several of them yesterday (posting as SsnapCracklePop) and they all sank like a stone, so I'm not sure if there is still a lot of interest in finding a solution ... My guess is a lot of people just gave up. You could consider posting a thread describing your proposed solution, or emailing some of the people who posted previously to see if they're still trying to solve the .1 problem.

I've been considering the simplest solution--actually buying a center channel. There is a Paradigm CC-170 center speaker on craigslist right now I might go look at. It's not a perfect timber match for my Mini Monitors--it was designed to match with the smaller Atoms. Besides that, there are two main problems--one: fitting it under my LCD monitor, and two: trying to explain to my wife why I have added yet another speaker to our house when I promised I wouldn't buy anymore ... Your solution, Doctor, might be a lot more elegant--not to mention less visible.

[Marvel]

Awesome. I thought I knew a little about audio but I'm a total ignoramus compared to you. I think I'll order that part, though I'll have a hell of a time explaining what it does to my wife ("I thought you weren't going to spend any more money on speaker stuff!")

That's a good one...[]

Bruce

[DrWho]

crap - I'll post a schenematic tomorrow.

[Static]

I took one of my rear speakers and put it beneath my monitor to get a feel for what it would sound like ... I'm not so sure I like it. Because the center speaker must go beneath the monitor, there's a distinctive change in the sound when panning across the front ... I'd like to know how much you would charge, DrWho, to provide me with the device you outlined ...

[DrWho]

Yea, my computer bit the dust and it'll be a bit before I get the backups uploaded...We're moving into finals week so I'll be swamped with school.

To do it yourself would cost under $12 and you could even get all the parts at your local radioshack. It's prob a bit cheaper online, but then you gotta wait for shipping and all that. If I were to build one for someone, then I'm probably going to charge around $40 shipped to your door - things are rather busy with school and soldering isn't exactly fun. I've no problems helping others figure out how to do it though. I figure about 90 minutes of labor if you have all the right tools.

[Static]

I'd be willing to take a crack at it myself. I have a soldering iron. I'm not exactly a wiz at it, but if the parts are that cheap I suppose I could afford to screw it up a couple of times.

Sorry to hear about your computer!

EDIT: I went back to your original solution using F L and R pre outs to sub -- and figured out a way to get the Xfi card to filter bass from the rears to the fronts. Now it sounds like I'm getting bass from all four speakers. I was just about to buy a center channel today too. I'm still interested in seeing your design, but I think your prior solution might just work out for the best. You have my gratitude!