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notphilmitchell
09-05-2008, 11:01 AM
Our living room is a secondary viewing/listening 5.1 area and full of compromise. I use Paradigm speakers. To mollify my wife, the tv is tucked in an antique cabinet with the center channel above, the fronts are inwall, the surrounds are in-ceiling, the PS1200 sub is tucked behind a chair in the corner. I recently added an Onkyo 606 for the auto-calibrating and auto-eq features. This helped with the fixed speaker placement in the room.

However, I'm still not happy with it. Because of convenience, it seems like it is our primary area. The problem is that the large center channel (CC350) is too high and positioned towards one seating area. There is no other place it can go and since I'm usually in the other seating area, it bugs me.

What I'm wondering is if I can use two smaller bookshelf speakers (MiniMonitors) in place of the single larger center channel. That way, I can put them lower and inside the cabinet and angle one towards each seating area. Theoretically, dialogue would be easier to hear and it wouldn't have to be as loud as it would be more focused.

I know I can't just plug both in to the center channel speaker output. I guess I could buy a a two-channel amp and feed the center output to it. But, since I just bought a new A/V receiver, I'm not excited about spending the money on an amp. I'm wondering if I can use a less expensive device like a speaker selecter (one that enables you to hook up multiple sets of speakers) to enable both the center channel speakers?

Anybody have thoughts on this or can recommend alternatives? Anyone have a product recommendation? Thank you!

pixelthis
09-06-2008, 08:32 PM
IF YOU are bound and determined to make your current situation
work, you might try aiming your center off kilter, a little more towards your spot.
Truth is its not just your center, probably nothing is going to sound right
where you're sitting, you just notice the center because its the main source of sound in a movie soundtrack.
If you think another center will help(I dont) you can try it this way.
if your receiver has line outs take the center line out and plug it into
an unused input(lets say right side).
Wire you 2nd center to your "zone b" right side.
Select the zone b source as the one your center line is plugged into.
I use this for my sub because it blew its plate amp.
It will tell you if a new center will help, but I AM DOUNTFULL ABOUT THAT.
Sounds like a band aid on major room speaker placement problems:1:

Mr Peabody
09-06-2008, 09:31 PM
I feel you would have to get the center speakers more directly above or below the TV to help. Your idea might help as the sound would be more directional toward you but if it's not close enough to the TV to associate the sound to the action or people speaking on screen then you still aren't going to be happy. If you could utilize a shelf directly below the TV then your idea would be fine. Any room on the sides of the TV?

Looking at the 606 you will have to use something like a switcher, according to what I saw you do not have a center pre out. You would have to be sure the switcher was the kind to keep the impedance stable.

E-Stat
09-07-2008, 06:12 AM
I know I can't just plug both in to the center channel speaker output.
You can, but would need to wire them in series (rather than parallel) which admittedly is less desirable. The Onkyo receiver is only rated down to 6 ohms - paralleling two 8 ohm speakers would drop the load to 4 ohms. Wiring two 8 ohm speakers in series would be 16 ohms.

rw

Mr Peabody
09-07-2008, 05:51 PM
Onkyo is a high current design, wouldn't you think the 4 ohm would be better than 16 ?

I had a 4 ohm sub on a bridged car amp, a high current PPI, when I added a 2nd 4 ohm sub I wired them in series thinking since the amp sees half the load bridged it would be perfect. To my surprise the sound was not good. The amp didn't seem to be able to drive the 2 subs as good as the one, no punch and less drive. I wired them in parallel just to see what would happen and they were slamming. I was a bit leary to leave it like that because of the low impedance the amp was seeing but it worked like that with no problems.

On the other hand I understand the Onkyo's run warm anyway, running a lower impedance will increase the heat so the ventilation would have to be ample. And, hopefully the 606 has good protection circuits just in case.

I really have not used any speakers over 8 ohms, if it was only a power thing that could be adjusted inside the set up menu but would 16 ohms effect the sound quality as I experienced?

pixelthis
09-07-2008, 09:07 PM
Onkyo is a high current design, wouldn't you think the 4 ohm would be better than 16 ?

I had a 4 ohm sub on a bridged car amp, a high current PPI, when I added a 2nd 4 ohm sub I wired them in series thinking since the amp sees half the load bridged it would be perfect. To my surprise the sound was not good. The amp didn't seem to be able to drive the 2 subs as good as the one, no punch and less drive. I wired them in parallel just to see what would happen and they were slamming. I was a bit leary to leave it like that because of the low impedance the amp was seeing but it worked like that with no problems.

On the other hand I understand the Onkyo's run warm anyway, running a lower impedance will increase the heat so the ventilation would have to be ample. And, hopefully the 606 has good protection circuits just in case.

I really have not used any speakers over 8 ohms, if it was only a power thing that could be adjusted inside the set up menu but would 16 ohms effect the sound quality as I experienced?

I doubt if the power draw in home use would make much diff, unless you really turned it up, but I hate hooking up two speakers to an output,
for some reason.
And I dislike two centers unless its a huge screen thats needs two for coverage.
The fundamental problem is room dynamics, and unless you fix a fundamental problem a band aid is only gonna be a compromise:1:

RoadRunner6
09-07-2008, 09:17 PM
This a very interesting thread. I wish I knew more about your exact setup like what in wall units you have and if there is room above the cabinet for an in wall center channel. This is one thread where a photo would have really been great.

Many people are not aware of the fact that the very best arrangement for the left, center and right speakers are 3 identical speakers in a curve so that all three speakers are the exact same distance from the listener. The is sometimes possible with either floor speakers or bookshelve speakers but is usually not practical for most HT setups. An option is to have a center channel that is a smaller model in the same series as the left and right with the same exact tweeter and possibly the same midrange. The center is placed vertically just like the left and right. I personally have a small condo and have all three fronts with the same exact small bookshelf model and all placed in the vertical position. The front soundstage is beautifully smooth with the exact same voicing/timbre across the front.

Unfortunately, this is seldom desireable for most buyers even though sonically it is the superior orientation. Thus the center channel laid over on its side was designed and marketed for practical HT considerations. There are problems with this horizontal placement of the center speaker. One of the main problems is what you are experiencing, poor lateral dispersion. As one moves off axis (to the left or right from dead center) the sound of the center channel speaker changes). My system consists of speakers that have a very good wide dispersion as your left and right probably also have. I can sit in the middle (directly in front of the center speaker), left or right side of the sofa and still virtually hear the exact same sound from the center channel. With a horizantal center speaker even with the same tweeter, I would loose this flexibility in seating without some sound changes. I am pointing all of this out so you will understand my possible suggestions.

Normally it is not the best idea to mix in wall mains with a conventional center channel speaker. In your case you have the center channel closer to you than the left and right. You have to allow for this distance variation in your speaker setup or the auto setup in your 606. Do you have the center channel volume higher than the left and right? Sounds like you might be cranking up the center to increase the dialog. Your current CC350 should be slightly tilted down so that the tweeter is pointing directly at the listeners ears.

One possiblity (don't laugh) is to place the CC350 on its side. I know this might look rediculous and not be stable or practical but you might find that this vertical placement gives you much better off-axis sound from the center channel in your favorite spot.

Another possibility would be to go with an in wall speaker identical to or slightly smaller (but with the same tweeter) than your left and right in walls. This of course would only be possible if you have wall space above and behind your cabinet. If this would put the center considerably higher than the mains then perhaps you could install it tilted down (I don't think the Paradigm's have a movable tweeter?).

Another option would be to buy a small bookshelf speaker in the Paradigm line that you would place above the cabinet in place of the CC350. Hopefully it would have either the same or nearly the same tweeter as in the in wall left and right. This would of course be placed in a vertical orientation and tilted slightly down if necessary. This should give you much better horizontal dispersion of the center channel sound. Don't worry about the smaller bookshelf as the bass below 80hz or so is redirected to the sub.

As far as two small center speakers there are several problems. One is finding a speaker that is a very close voice/timbre match for your left and right speakers. Hopefully this would be a Paradigm speaker with a rating of 8 ohms. Note that some 8 ohms rated speakers actually go closer to 4 ohms in certain frequencies. You would need to read a review or call Paradigm to make sure it is really stays close to 8 ohms. That Onkyo might be only officially rated down to 6 ohms but I wouldn't worry. The test results I saw indicate it has a strong amp and tests very well at 4 ohms (for wiring them in parallel). In the 90's some of the Sony surround receivers actually did have a double center channel speaker terminals.

Perhaps if you have enough room just one bookshelf speaker inside or under the cabinet might do the trick.

Good Luck....RR6 :p

E-Stat
09-08-2008, 04:53 AM
Onkyo is a high current design, wouldn't you think the 4 ohm would be better than 16 ?
Just going by their recommendation of using speakers between 6 and 16 ohms. Parallel is certainly advantageous if possible.

Onkyo 606 specs (http://www.onkyousa.com/model.cfm?m=TX-SR606&class=Receiver&p=s)

rw

Mr Peabody
09-08-2008, 06:55 AM
Something like this?

http://www.amazon.com/Adcom-GFS-300-Speaker-selector/dp/B000BIW1B2

You can probably search around to find one cheaper. Check your local Radio Shack

Feanor
09-08-2008, 10:24 AM
...

What I'm wondering is if I can use two smaller bookshelf speakers (MiniMonitors) in place of the single larger center channel. That way, I can put them lower and inside the cabinet and angle one towards each seating area. Theoretically, dialogue would be easier to hear and it wouldn't have to be as loud as it would be more focused.
...
Anybody have thoughts on this or can recommend alternatives? Anyone have a product recommendation? Thank you!

What angle are your two listening areas with respect to each other and the screen? If not greater 50-60 degrees, two speakers would seem to be unnecessary since the dispersion of your current, single center channel should be adequate. Otherwise two (smaller) identical speaker, each angled towards one listening area, ought to work well.

First try two 8 ohm spearkers connected in parallel, keep the volume low initially then increase, and watch for the receiver getting warmer than usual. If you notice any more heat, try a serial hook-up. But the power delivery could be quite limited a 16 ohms.

f0rge
09-09-2008, 06:19 AM
i like RR6's idea, go to a paradigm dealer and get an in-home demo, put one bookshelf speaker on top of your cabinet instead of the CC350, see if that helps, if not, you can just bring it back.

or if possible just try pointing the center to where you sit most, as long as you're happy who cares about the other people watching lol...

pixelthis
09-09-2008, 10:41 PM
Something like this?

http://www.amazon.com/Adcom-GFS-300-Speaker-selector/dp/B000BIW1B2

You can probably search around to find one cheaper. Check your local Radio Shack


A LOT cheaper.
You can hook the ground of both to the same ground pole, no problem,
you only need a two position switch for the positive side.
A lot cheaper than 220 bucks:1:

notphilmitchell
09-12-2008, 12:31 PM
Thanks for all of the discussion on this- I was travelling and the hotel charged $10 a day for internet. On top of the $$$ rate, I thought it was a rip, so I'm just checking back in.

I'm going to answer more when I'm home over the weekend but: I am using Paradigm AMS-250s v3 for the fronts. They are mounted on either side of the antique armoire about eigh feet apart. The tweeters are at about 38 inches off the floor. The center (I can't remember if it is a Paradigm CC370 or CC350- it is also a v3) is actually inside the cabinet but up as high and as far back as it can go to allow the TV to fit. It is approximately 54 inches off the ground and 10 inches back in the cabinet. Its got about 7 inches of cabinet on each side- so it is too far within the cabinet but is two wide/tall to fit anywhere else. I'd tried putting it on top but apparently that is where a big basket of dried flowers has to go...

The room is fairly small - probably 14x14. The surround speakers are Paradigm 100Rs v3 and are mounted in a ten foot ceiling about two feet from the back wall and about a foot further outside each of the fronts. This puts them a foot or so behind and a couple feet to the side of each chair. The sub is a Paradigm PS1200 placed in the front corner such that it makes the fireplace screen rattle annoyingly at much volume.

I haven't noticed much of an issue with the 606 generating a lot of heat- it probably hasn't been on long enough or pushed hard enough. I've really only done the auto-setup and calibration on it and played around with some 5.1 DVD music. I've already got a couple sets of Paradigm MiniMonitors (v1 and v3) so I wouldn't need to purchase them. The armoire has a center brace and two shelves (actually, four drawers were originally there) underneath the TV where the 606, HDDVD, SACD and MonsterPower HTR2500? fit. My thought was putting one MiniMon in each of the slots that were directly below the TV, stacking the DVD and SACD, and hiding the MonsterPower elsewhere.

I've got a Paradigm CC300 (which is a larger box) in my family room setup. It is bi-wired (I think that is the term) where I've got two sets of cables running from the receiver's cemter output to the two sets of jacks (the jumpers are removed) on the speaker. I've read that this is fine (or preferable- depending on who is posting) but that running two separate speakers is not advisable. Is this correct?

Mr Peabody
09-12-2008, 04:59 PM
With the addition of that information you are definitely on the right track. Your center was too far back that the sides of the cabinet was giving it a horn effect and blocking most of the disspersion. Putting the mini's where you plan will accomplish to improvements, one the sound will better be associated with the screen, and two, you can put the mini right out to the edge of the shelf so it can fire into the room better. My guess is that it wouldn't hurt to hook up two centers to the output, it sounds like you don't crank it that loud anyway, just proceed with caution and keep an eye on the receiver until your comfortable there won't be a problem. Most receivers have protection circuits built in so it would probably shut down before any damage if there was a problem anyway.

notphilmitchell
09-15-2008, 07:08 AM
I thought I'd try things incrementally. I replaced the larger center channel that was up high and too far back in the cabinet with a single MiniMonitor positioned below the TV. I've got it slightly angled toward the primary seating area.

The MiniMonitor is a single 6.5" driver with a 1" tweeter above it. It has a single rear port. As it is now sitting horizontally, does it matter which (driver or tweeter) is positioned closer to the center? I've got the tweeter on the outside because the speaker is in a small shelf. The tweeter side (outside) is flush with the shelf and the inside edge of the speaker (driver) angled about three inches inside the cabinet. I thought the inset might impact the tweeter more than the driver.

I ran the Audessey setup and I think it sounds quite a bit better- more crisp, brighter, and more focused. The larger center was just getting lost up where it was. I'm going to try it like this for the week and possibly try to add the second this coming weekend. I'm a little concerned that since it is a relatively small space that two firing in slightly different angles might hurt rather than help.

Mr Peabody
09-15-2008, 04:39 PM
I think you would be fine having the smaller speakers just firing forward since you don't have to push them back. Just put the two end to end and sit them there like a center would sit. Dispersion from the monitors should be fine unless you sit way off to the side. Then you are probably getting blown away from which ever main you are in front of anyway.

Is the shelf too small to stand the monitors up?

notphilmitchell
09-17-2008, 05:55 AM
Yes- the shelf is too small to stand the speaker up. The shelf (one of four compartments- a two by two grid) is about 18" wide by 8" high by about 20" deep. If I could have removed the divider between the two upper compartments, I would have put the larger center (about 8"tall 20"wide 10"deep) in that space. So, instead I'm currently using one MiniMon (about 12" tall, 8"wide, 10"deep) in one of the compartments and think I may try the other in the other compartment beside it.

With the 606, do you think it would be better to run two sets of cables (one to each speaker) from the 606's center output. Or, run one cable from the 606's center output to the center speaker 1 and then another cable from center speaker 1 to center speaker 2?

Mr Peabody
09-17-2008, 05:59 PM
I really don't know if it would make a difference but I'd personally go from the receiver to each. It just seems more uniform that way.