Question about moving from 5 to 7 speakers

[mlundy57]

I currently have a 5 channel surround system set up with
Klipsch Reference Series speakers. My
current configuration is as follows:

Front RB-81
II

Center RC-62
II

Surround RS-41
II

My question concerns adding additional speakers to move up
to a 7 channel system. My listening area
is a 13 x 20 x 8 space in a 20 x 25 x 8
room.

Questions:

(1) Should I add a second set of rear surround
speakers (i.e. RS-41 II, 42 II, or 52 II) or should I use a pair of monopoles
for the rear surround (i.e. RB-42 II or RB-52 II).

(2) If surround speakers should they be the same
size.

(3) If I did use different sizes, should the
larger speakers be used as the surround or surround back speakers?

Thank you

[mustang guy]

Welcome to the forum!

It seems to me like you have a well balanced system. I didn't see mention of a sub. If you don't have one, I would shop there first. Would you like recomendations on a sub?

[mlundy57]

Currently I am using a 100 W10" Sony sub. It works OK but will be replaced in the next few months. I'm considering a Klipsch SW-112.

[Youthman]

Welcome to the forums. You have a great system to work with.

My listening area
is a 13 x 20 x 8 space in a 20 x 25 x 8
room.

My room is 13' x 19 with 10' ceilings.

If you choose to move from a 5ch to a 7ch system, if your receiver has preouts, I would HIGHLY suggest getting an amp. I had a Yamaha RX-V1800 7.1 receiver that claimed 130 watts x 7 with all channels driven. From my personal experience as well as third party bench testing, the Yamaha dropped from around 90 watts per channel with 5 speakers down to a measly 55 wattts per channel with 7 channels driven. I had RF-83's with an RC-64 up front and RS-52's as side surrounds and added a pair of RB-35's as back surrounds. For my setup, there was no sonic benefit to adding the back surrounds and it actually was a let down when I did add the surround back speakers because it reduced the overall performance of my entire system.

If you do decide to add surround back speakers, I would recommend using your RS-41 II as side surrounds since they are wide dispersion and using a direct reflecting type bookshelf speaker for the back surrounds. I would think the RB-41 II would be just fine for back surrounds since there won't be that much information that they play anyways.

Hope that helps.

[Youthman]

Currently I am using a 100 W10" Sony sub. It works OK but will be replaced in the next few months.

You will be blown away (pun intended) when you move to a better sub. [] I have not heard the SW-112 subs. Actually, I just recently purchased an RSW-15 and have been amazed at how well it has performed. I have always loved and owned Velodyne subs but the RSW-15 has really impressed me for sure. I posted some pics of it and even a comparison of it and my Velodyne HGS15 sub here.

So far, I've been so pleased with the RSW-15, I will likely be selling one (or even both) of my Velodyne HGS15's in the near future.

[mlundy57]

Thanks. I'm powering the sysetm with a Marantz SR5007. The Marantz seems to run about 55 W per channel with 7 channels driven which seems to be plenty of power when driving the the Klipsch Reference Series speakers due to their high sensitivity.

[Youthman]

I guess I just found it underwhelming when I added the extra two speakers. I had to really crank my receiver way up and it still didn't sound as good as it did with only 5 speakers.

[derrickdj1]

Klipsch are easier to drive than most other brands but, there is no subsitute for adquate power. Bookshef and other smaller speakers in the Klipsch lines may benefit form more power than the tower speakers. For example, a 3 db drop in sensitivity means that the speaker requires 2 x the power to achieve the same spl. Some people like amps for the power and to be able to handle ithe impedance dips of the RF 7, 83, 63 and 64 and other large series speakers. All speakers have wide impedance swings which may benefit from a good amp/avr especially. when diving a lot of speakers.

[Youthman]

For example, a 3 db drop in sensitivity means that the speaker requires 10x the power to achieve the same spl.

Derrick, I believe it takes 2x the power to yield a 3db increase in volume.

[derrickdj1]

Thanks for catching that: I edited the post[:#]

[mustang guy]

For example, a 3 db drop in sensitivity means that the speaker requires 10x the power to achieve the same spl.

Derrick, I believe it takes 2x the power to yield a 3db increase in volume.

It takes ten times the power to be "percieved" as twice as loud. That is 10db louder.

[mustang guy]

Currently I am using a 100 W10" Sony sub. It works OK but will be replaced in the next few months. I'm considering a Klipsch SW-112.

You definitely need a sub before you buy any more speakers. That Sony is a 23 watt 6.5" sub. It doesn't belong in the same room as a reference setup. You would need about 13 of them!

The RSW-15 mentioned earlier is a great sub. There are a lot of other subs out there that are not Klipsch. Anything from SVS is good as many will attest. Velodyne and Paradigm make great subs too.

Recently, one of our forum members, ivanhurd wrote a review on a system somewhat similar to yours. Here is the link: http://community.klipsch.com/forums/t/164407.aspx He is using the SW-115, which is a relatively new sub from Klipsch, and very well liked. That is definitely not allways the case!

[mlundy57]

The current model for the RSW-15 is the SW-311 which is what Klipsch recommends for the RB-81 II HT setup. Unfortunately, at $1,600 this is way outside my price range at this point. At $600 the SW-112 is in my price range and is 300 Watts with a range of 26 - 120 Hz. The SW-115 would be a stretch price wise ($850) but would probably fir better at 400 Watts with a range of 18 - 150 Hz. The Sony SA-W2500 is 100 watts with a 10" cone and a 28 - 200 Hz range. It is left over from the previous setup which was Klipsch Quintet speakers. I'e been upgrading the system a little bit at a time each month.

[Chris A]

I guess I just found it underwhelming when I added the extra two speakers. I had to really crank my receiver way up and it still didn't sound as good as it did with only 5 speakers.

There are multiple psychoacoustic studies that show that speakers that are arranged more than ~135 degrees from center front will have no additional benefit because human hearing is not sensitive to those azimuths between 135 and 180 degrees from centerline. In fact, azimuths greater than 120 degrees have steeply diminishing returns on perceived surround sound envelopment.

Chris

EDIT: relevant papers on this subject include--

1) Hiyama, Komiyama, and Hamasaki (2002). "The Minimum Number of Loudspeakers and its Arrangement for Reproducing the Spatial Impression of Diffuse Sound Field", 113th Convention, Audio Eng. Soc., Preprint 5674

2) Muraoka and Nakazato (2007), "Examination of Multichannel Sound Field Recomposition Utilizing Frequency-Dependent Interaural Cross Correlation (FIACC)," J. Audio Eng. Soc., 55, pp. 236-256.

Or you can just invest in Floyd Toole's book: Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms, 2008, Elsevier Ltd.

[ivanhurd]

Thanks mustang guy for the linkage! mlundy, if you call the dealers, you can most likely get the SW-115 for around $650-$750. I got mine for $600, but I bought it as part of a package deal, so I'm sure that knocked the price down a bit. I love my 115, and I am willing to bet that most others would too =^) And get some direct firing speakers for the back. I've read that either/or sounds good, some prefer direct for the sides, wide dispersion for the back, it'd just take some trying of both to see what you prefer but I have the RS-62IIs on the side and 81IIs in the back and I think it's great.

[Chris A]

From my personal experience as well as third party bench testing, the Yamaha dropped from around 90 watts per channel with 5 speakers down to a measly 55 wattts per channel with 7 channels driven.

BTW: 90/55 is 2.1 dB (power ratio), which isn't very much difference (aurally).

[Youthman]

BTW: 90/55 is 2.1 dB (power ratio), which isn't very much difference (aurally).

All I know is aurally, I wasn't impressed at all. I was actually very disappointed and I didn't know why. It wasn't until several weeks later that I came across a 3rd party benchmark that revealed on paper what my brain was telling me. All I knew is I had to really crank up my receiver MUCH more than I had when running 5 speakers and even at the same percieved volume, there just wasn't the same impact as I got with only running 5 speakers. Any 7.1 can generate sound through 7 speakers but I just don't believe most receivers can "effectively" drive 7 speakers.

[mlundy57]

Thanks Ivanhurd, that's good to know. I have been using the process of "buying on wait" to get my speakers. That is, I wait until I find what I want at a price I'm willing to pay. I've never tried negotiating with the big online retailers. My local big box store will negotiate some and while they do carry Klipsch speakers, however they do not carry the reference line. There is a smaller local dealer that does carry the reference line (that's where I got the RS-41 II's). I'll see what kind of price he'd be willing to make on the SW-115.

[ivanhurd]

You don't really have to negotiate, you just call around to find the best deal, then see if your local guy is willing to beat it. When I first went to my local guy he quoted me a price that I was quite happy with compared to the MSRP price I was seeing online. Then last second I decided to try calling around, got a way better price, went back to the local guy and he ended up beating it. A little homework saved me almost a grand so I was able to upgrade my surrounds and rears and sub.

[Islander]

I agree, Youthman. I have a 7.1 receiver, but its amp is just being used to power the front centre, surrounds and single rear surround. That's four speakers, if it wasn't clear, and the front centre is a Belle, which is pretty sensitive at 103dB.

The main JubScalas are bi-amped with a pair of 500Wpc Yamaha MX-D1 power amps, and the overall sound is really good.

However, it's not just about the power. Good-quality power amps will have much better sound than nearly any receiver's amp. While I was waiting for some of the parts for the JubScala conversion, I temporarily connected one of the MX-D1 amps to the side surround Heresy IIs. The improvement in clarity was really obvious. If it fit my budget, I'd be looking for another pair of MX-D1s to power the four speakers that the receiver is currently driving, but that would be pretty extravagant.