I want to know how bad it is going to sound, or if I'm ok. We're redoing our living room, and installing in-wall speakers. I just wanted good speakers and a 7.1 setup (using a Denon AVR 2310 CI) receiver so it can split 5.1 into 7.1), so what i initially did is this:
The center WAS going to be an Polk MC85 on its side.
The L/R fronts are Polk RC85i's (rectangles).
The L/R sides AND L/R rears Polk RC80i's (round).
The subwoofer is a Velodyne SC-600.
After I had bought all the speakers and they were being set up, my question of "is this center going to be awesome?" was answered with "yeah, it'll be ok" which prompted my "Only ok?" which was answered with "yeah, it'll be ok. It's just not a center speaker and only has one tweeter so it won't be as strong as a normal center."
Not realizing the differences in ohm's, I went back to the phone to where I bought the speakers and found out that the only in-wall center Polk makes is something called a "LCiC" (http://www.polkaudio.com/customaudio/lc ... .php#lci-c) - but it cost a whopping $600 bucks. Going online, I found a place selling it for $317 and decided that I wanted a real center speaker. I purchased the LCiC (which is in the mail) and returned the MC85.
It was around here that I was told "cool center, but it's 4 ohms," to which I replied "So?" and was answered with "well, the other speakers are 8 ohm speakers" to which I stared at the guy and said "So?" and the was told that a 4 ohm center and 8 ohm fronts will ruin my surround sound and that I'm going to be able to hear a big difference anytime a sound moves from left to right or right to left from the front speakers because a "4 ohm speaker is a lot stronger then an 8 ohm speaker" - he then went on about how the Polk RC's are more geared toward audio (listening to CD's, etc) then movies, which they hadn't mentioned before... also, EVERY review I've read on the 'net about the RC85i's and RC80i's have been nothing but positive toward being used as in-wall speakers.
So anyway, the current setup (waiting on the RCiC in the mail) will be:
Denon AVR 2310 CI Receiver.
Polk LCic center.
The L/R fronts are Polk RC85i's (rectangles).
The L/R sides AND L/R rears Polk RC80i's (round).
The subwoofer is a Velodyne SC-600.
Will the LCic ruin my 7.1 surround sound system or am I overreacting?
Help! 8 ohm L/R fronts paired with a 4 ohm center
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lordshiva
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eliwhitney
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dadden
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Why do they need to be in wall mounted?
What are you going to be using for a video display device/system?
Errr, I realise that you have already purchased many or most of these items and may even own a few, so I will try and answer your question and offer some advise about how to think about what you want to do.
Based on the specs the center will be much brighter sounding. (just guessing but the much higher frequency response would indicate that possibility.)
A little less sensitive. I.E. It will be slightly less loud for the same wattage input. Therefor it will need more power and at 4 ohms it will require twice the current as the 8 ohm speakers which will make it a harder speaker to drive. If you have a decent power amp that can drive 100 to 150 watts into more than half of the channels simultaneously then it shouldn't be a problem.
Having said all of this I would need to listen very carefully to both speakers in person and installed correctly. I have always found that systems sound best (if quality is a consideration) when the L,C and R speakers are identical or nearly so. I.E. the Left and Right can be mirror images of each other and the Center not. But I still find that the sound is more consistent and moves more smoothly between speakers when all are the same or at least have an almost identical sound.
It bears repeating, the center speaker in a true Home Theatre set up is used harder than any other speaker excepting the Subwoofer. If it is brighter it will fatigue the listener because the dialog will grate on the ears and grow annoying. You will then find yourself turning the system down.
I would not turn the original choice on its side unless there is some positioning/space necessitating this move. I would recommending orienting the speakers so that the tweeter is closest to video display. I.E. if they are across the bottom of the screen then tweeters on top. If the are across the top of the screen then tweeters on the bottom. If the Center channel speaker needs to be on its side then check and see if the sound is different if you can and if so see if you can install the Left and Right on their sides (tweeters facing inwards) as well.
Good luck,
Brian.
PS. I just checked and the receiver that you say that you are using puts out 105 watts per channel (I'll assume into 8 ohms). It also doesn't have any pre-amp outputs. I assume that you already own this unit? If you can return items that you don't need/want I would try and check some how whether you are going to like the "real" Center channel speaker over the matched Center channel speaker. Also, if you can hear well you will probably notice a bit of clipping in the 4 ohm speaker over the 8 ohm speaker with only 105 watts unless that number is very conservative.
PPS. What is a "Real" Center Channel speaker? In most systems in Recording studios I have seen as well theaters (behind the screen) the Center channel speaker is exactly the same as the Left and Right. Sorry to keep repeating myself but horizontal Center channel speakers are almost always about prettiness and next about ease of placement and lastly about good audio practices and acoustics.
What are you going to be using for a video display device/system?
Errr, I realise that you have already purchased many or most of these items and may even own a few, so I will try and answer your question and offer some advise about how to think about what you want to do.
Based on the specs the center will be much brighter sounding. (just guessing but the much higher frequency response would indicate that possibility.)
A little less sensitive. I.E. It will be slightly less loud for the same wattage input. Therefor it will need more power and at 4 ohms it will require twice the current as the 8 ohm speakers which will make it a harder speaker to drive. If you have a decent power amp that can drive 100 to 150 watts into more than half of the channels simultaneously then it shouldn't be a problem.
Having said all of this I would need to listen very carefully to both speakers in person and installed correctly. I have always found that systems sound best (if quality is a consideration) when the L,C and R speakers are identical or nearly so. I.E. the Left and Right can be mirror images of each other and the Center not. But I still find that the sound is more consistent and moves more smoothly between speakers when all are the same or at least have an almost identical sound.
It bears repeating, the center speaker in a true Home Theatre set up is used harder than any other speaker excepting the Subwoofer. If it is brighter it will fatigue the listener because the dialog will grate on the ears and grow annoying. You will then find yourself turning the system down.
I would not turn the original choice on its side unless there is some positioning/space necessitating this move. I would recommending orienting the speakers so that the tweeter is closest to video display. I.E. if they are across the bottom of the screen then tweeters on top. If the are across the top of the screen then tweeters on the bottom. If the Center channel speaker needs to be on its side then check and see if the sound is different if you can and if so see if you can install the Left and Right on their sides (tweeters facing inwards) as well.
Good luck,
Brian.
PS. I just checked and the receiver that you say that you are using puts out 105 watts per channel (I'll assume into 8 ohms). It also doesn't have any pre-amp outputs. I assume that you already own this unit? If you can return items that you don't need/want I would try and check some how whether you are going to like the "real" Center channel speaker over the matched Center channel speaker. Also, if you can hear well you will probably notice a bit of clipping in the 4 ohm speaker over the 8 ohm speaker with only 105 watts unless that number is very conservative.
PPS. What is a "Real" Center Channel speaker? In most systems in Recording studios I have seen as well theaters (behind the screen) the Center channel speaker is exactly the same as the Left and Right. Sorry to keep repeating myself but horizontal Center channel speakers are almost always about prettiness and next about ease of placement and lastly about good audio practices and acoustics.
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lordshiva
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If you follow this link it shows that the Denon AVR 2310 CI *does* have pre-amp outputs... though maybe I'm wrong - it mentions pre-amps for the sub and "Multi-Zones" - http://www.usa.denon.com/ProductDetails/5011.aspdadden wrote: PS. I just checked and the receiver that you say that you are using puts out 105 watts per channel (I'll assume into 8 ohms). It also doesn't have any pre-amp outputs. I assume that you already own this unit? If you can return items that you don't need/want I would try and check some how whether you are going to like the "real" Center channel speaker over the matched Center channel speaker. Also, if you can hear well you will probably notice a bit of clipping in the 4 ohm speaker over the 8 ohm speaker with only 105 watts unless that number is very conservative.
Does that change things a little?
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dadden
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Your receiver of choice has a line out for a powered subwoofer and a stereo output for "Multi Zones" as you said but this is not the same as having "Pre-Amp" outputs. Pre-Amp outputs are discrete outputs for every channel that the surround processor generates. I.E. there would be a channel for LCR, Ls & Rs and LFE (Sub) for 5.1 and LCR, Ls, Rs, Lr, Rs and LFE for 7.1.
This doesn't make your receiver a bad piece of equipment but it does mean that if you wanted to use separate amplifiers at some point in the future you would be unable to do so. If you intended to never use more than the speakers that you specify in your original post and/or want to save money then I feel you will be OK with your choice of receiver.
As a point of reference I have a Pre-amp w/ a separate amplifier that has 5 200watt amplifiers that will drive 4 ohms to about 350 watts all at the same time. My speakers are M&K, a sadly defunct company (RIP).
I wanted the best possible sound and have a very reasonable wife who has very good hearing therefor the WAF doesn't come into play. On the other hand I spent at least $2000usd on speakers/sub and another $1600usd on the pre-amp/amplifier and they were bought use off of eBay and Audiogon. Whereas my wife bought our TV for another $3600usd straight from the Sony Style show room. We did get a good deal on that during the Thanksgiving day sale 2 years ago.
I tell you these things so that you have a reference as to where I am coming from. If you have space concerns, money concerns, wife concerns and aren't an audio engineer or at least an audiophile then you should be fine. I would still be a bit concerned about the difference between the two choices you have for center channel. I would also be very cautious when you are installing your speakers in the wall as the wall will for part of the sound system. This means that if the wall isn't rigid and the cavity doesn't have enough space (or possibly too much space) then your speakers will sound different. If this happens you won't get that immersive surround sound experience that you are seeking.
What are you using for your video display device? Are you getting a Flat screen of some sort or are you going to project on the wall or a screen?
Brian.
This doesn't make your receiver a bad piece of equipment but it does mean that if you wanted to use separate amplifiers at some point in the future you would be unable to do so. If you intended to never use more than the speakers that you specify in your original post and/or want to save money then I feel you will be OK with your choice of receiver.
As a point of reference I have a Pre-amp w/ a separate amplifier that has 5 200watt amplifiers that will drive 4 ohms to about 350 watts all at the same time. My speakers are M&K, a sadly defunct company (RIP).
I wanted the best possible sound and have a very reasonable wife who has very good hearing therefor the WAF doesn't come into play. On the other hand I spent at least $2000usd on speakers/sub and another $1600usd on the pre-amp/amplifier and they were bought use off of eBay and Audiogon. Whereas my wife bought our TV for another $3600usd straight from the Sony Style show room. We did get a good deal on that during the Thanksgiving day sale 2 years ago.I tell you these things so that you have a reference as to where I am coming from. If you have space concerns, money concerns, wife concerns and aren't an audio engineer or at least an audiophile then you should be fine. I would still be a bit concerned about the difference between the two choices you have for center channel. I would also be very cautious when you are installing your speakers in the wall as the wall will for part of the sound system. This means that if the wall isn't rigid and the cavity doesn't have enough space (or possibly too much space) then your speakers will sound different. If this happens you won't get that immersive surround sound experience that you are seeking.
What are you using for your video display device? Are you getting a Flat screen of some sort or are you going to project on the wall or a screen?
Brian.
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lordshiva
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From what I've been told, I will *never* have to change the sides and rears from the RC80i's because most of what I'll be getting out of them won't be as powerful as the front speakers, so I'm totally fine with keeping them RC80's. The main reason for the in-walls is I want the living room to look beautiful and not have speakers sitting around or hanging from the walls, and even unpainted the room is looking amazing - the receiver, PS3, etc. are all going to be housed in a BDI Avion 65' cabinet which really looks nice as well.
Anyway, eventually I want to upgrade the Front left and right from RC85's to the LCic equivelent which means they will dip down into the 4 ohm range as well. I don't know if it matters, another source said that speaker wire by its very nature has resistance, and if the LCic is a 4 ohm speaker, by the time it travels down to the receiver, it loses some power and would be around 6 ohm... I don't know if that's fact or fiction, just what I was told.
As for your question: we have a Samsung 50' plasma... forgot the exact model # but it looks *amazing* - the wife is perfectly happy with it but I strategically had the left and right speakers put far enough apart so down the road we can slap a 65' plasma/LED on the wall lol
Anyway, eventually I want to upgrade the Front left and right from RC85's to the LCic equivelent which means they will dip down into the 4 ohm range as well. I don't know if it matters, another source said that speaker wire by its very nature has resistance, and if the LCic is a 4 ohm speaker, by the time it travels down to the receiver, it loses some power and would be around 6 ohm... I don't know if that's fact or fiction, just what I was told.
As for your question: we have a Samsung 50' plasma... forgot the exact model # but it looks *amazing* - the wife is perfectly happy with it but I strategically had the left and right speakers put far enough apart so down the road we can slap a 65' plasma/LED on the wall lol
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dadden
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To address some very important points for you...
Make sure that your PS3 is very well ventilated and when you first start using it check it regularly. I have one and like it very much and it runs extremely HOT! I am talking hot by professional gear standards. I have mine on a deep open shelf that has a 2 inch hole in the back for for cabling and it still runs so hot that I am considering either moving it or making more holes in the back of the cabinet or fan venting the cabinet. That's what the pros do and I am just debating whether or not it is worth the considerable hassle.
If you get 2 ohms in your speaker wire then you need bigger wires. You are installing your cables in the wall. Therefore I would recommend that you use stranded 12 gauge wire. It doesn't have to be Monster or any other brand. It just has to be copper and big. Also speakers have impedance as well as straight resistance. It measures out in ohms which is the same but it really isn't the same to your amplifier. Don't worry about it. Just get the biggest gauge wires you can install. Install them and if they are 12 or 10 gauge you won't ever have to think about them again. Oh, and leave a service loop in the wall at both ends so that you can move things around in there if necessary in the future. Also, I would suggest that you use some sort of crimp on spade lug or other that works with the terminals unless your wall boxes and speakers come with euro style barrier strips or some other compression fitting for the wiring. You want full contact with the wires and you want to guarantee that it doesn't come undone. I have done install work for years and we always use some sort of crimp lug for anything like this. The connection must be 100% secure. If you are really particular you can solder the crimped connection after you crimp it. And get a crimping tool.
As I said before it depends on what you want. And you seem to know what you want. So... If you have already installed your L and R speakers then I would stick to the same speaker for the Center. Most people like to wall mount below the screen but I have heard above as well and it sounded very nice. Remember to put the tweeter closest to where you want the sound to come from. Your choice for location is going to be determined by the watching height of the screen vs. your listening height (where your ears are going to be) vs. locations of anything that might block the Center channel speaker. Another thought, no matter how hard it is I can't recommend strongly enough that the center channel be centered above or under the screen. It doesn't take much to shift the dialogue localisation cues and ruin the illusion that the actors on screen are actually speaking to you.
Finally, I wouldn't worry too much about the future upgradability of your receiver. When you get to that point you will probably want more powerful speakers therefore need more powerful amplifiers. Plus if the technology changes, and it usually does, then you won't mind having to upgrade the processors in your receiver at that time. Meanwhile, you will have saved quite a bit of money on this side of the exercise.
Good luck,
Brian.
Make sure that your PS3 is very well ventilated and when you first start using it check it regularly. I have one and like it very much and it runs extremely HOT! I am talking hot by professional gear standards. I have mine on a deep open shelf that has a 2 inch hole in the back for for cabling and it still runs so hot that I am considering either moving it or making more holes in the back of the cabinet or fan venting the cabinet. That's what the pros do and I am just debating whether or not it is worth the considerable hassle.
If you get 2 ohms in your speaker wire then you need bigger wires. You are installing your cables in the wall. Therefore I would recommend that you use stranded 12 gauge wire. It doesn't have to be Monster or any other brand. It just has to be copper and big. Also speakers have impedance as well as straight resistance. It measures out in ohms which is the same but it really isn't the same to your amplifier. Don't worry about it. Just get the biggest gauge wires you can install. Install them and if they are 12 or 10 gauge you won't ever have to think about them again. Oh, and leave a service loop in the wall at both ends so that you can move things around in there if necessary in the future. Also, I would suggest that you use some sort of crimp on spade lug or other that works with the terminals unless your wall boxes and speakers come with euro style barrier strips or some other compression fitting for the wiring. You want full contact with the wires and you want to guarantee that it doesn't come undone. I have done install work for years and we always use some sort of crimp lug for anything like this. The connection must be 100% secure. If you are really particular you can solder the crimped connection after you crimp it. And get a crimping tool.
As I said before it depends on what you want. And you seem to know what you want. So... If you have already installed your L and R speakers then I would stick to the same speaker for the Center. Most people like to wall mount below the screen but I have heard above as well and it sounded very nice. Remember to put the tweeter closest to where you want the sound to come from. Your choice for location is going to be determined by the watching height of the screen vs. your listening height (where your ears are going to be) vs. locations of anything that might block the Center channel speaker. Another thought, no matter how hard it is I can't recommend strongly enough that the center channel be centered above or under the screen. It doesn't take much to shift the dialogue localisation cues and ruin the illusion that the actors on screen are actually speaking to you.
Finally, I wouldn't worry too much about the future upgradability of your receiver. When you get to that point you will probably want more powerful speakers therefore need more powerful amplifiers. Plus if the technology changes, and it usually does, then you won't mind having to upgrade the processors in your receiver at that time. Meanwhile, you will have saved quite a bit of money on this side of the exercise.
Good luck,
Brian.
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ANonemoose
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You really should have impedance matched speakers. Putting four ohm speakers on an eight ohm A/V system is liable to overheat the receiver, if I remember correctly. The impedance formulas will explain why you want to match the speakers to your receiver's speaker ratings. There's a wealth of information about speakers on the Net. Just Google "speakers" and you'll see many links on how to set them up.
I have a large family room (actually a suite) and use all Polk speakers that are matched in impedance. I have a $400+ center speaker and it is awesome. So big that I don't know how I'll be able to use it if I buy a new TV that won't accommodate it because of the size of the TV's base. I have a two year old 58" Panny plasma that does allow me to put the center speaker on the stand, but even that made me nervous and I secured it with angled brackets.
Again, I'd be careful with the four ohm speakers if your receiver is not rated for four ohms. Mine is rated for 8-16 ohms.
Rich
I have a large family room (actually a suite) and use all Polk speakers that are matched in impedance. I have a $400+ center speaker and it is awesome. So big that I don't know how I'll be able to use it if I buy a new TV that won't accommodate it because of the size of the TV's base. I have a two year old 58" Panny plasma that does allow me to put the center speaker on the stand, but even that made me nervous and I secured it with angled brackets.
Again, I'd be careful with the four ohm speakers if your receiver is not rated for four ohms. Mine is rated for 8-16 ohms.
Rich
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hdtvjim
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Yes you can use a 4 ohm center with 8 ohm L/R fronts.
To understand this a bit better, first realize that all amplifiers are designed to deliver a signal into an electrical "load" or resistance presented by the loudspeaker. We measure resistance in units called "ohms".
Conventional wisdom makes an 8 ohm loudspeaker load the most acceptable because it "protects" the amplifier from delivering too much current. A 4 ohm loudspeaker can encourage a marginally designed amplifier to deliver more current than it comfortably can.
However, you should remember that a loudspeaker
To understand this a bit better, first realize that all amplifiers are designed to deliver a signal into an electrical "load" or resistance presented by the loudspeaker. We measure resistance in units called "ohms".
Conventional wisdom makes an 8 ohm loudspeaker load the most acceptable because it "protects" the amplifier from delivering too much current. A 4 ohm loudspeaker can encourage a marginally designed amplifier to deliver more current than it comfortably can.
However, you should remember that a loudspeaker