Crossover Frequency adjusted Frequently

Dr Air

I have been enjoying my Polk System for a few years, it was what I bought out of our home renovation funds. I invested in a system that would serve my needs so that I would not have to upgrade to soon. My system consists of the LSI series: LSI 25 fronts, LSI/C, LSI/fx surrounds, and a PSW 505 sub all driven with a Denon AVR 4306. It is powerful enough but it seems that "something" is missing. It is like there is a hole in my listening zone if that makes sense? I have been working with the crossovers and have had some improved response but am not sure what to listen for. Reading some of the veterans' wisdom here makes me realize that I am still a newbie! So, where do I start?

ViperZ

The first advice that you will get here is that even though your receiver is a beast, you're still underpowering the LSi25 towers. Get a good 2-channel amplifier (Adcom GFA-555/555II, Carver TFM-25/35/etc, parasound, rotel, emotiva, whatever sounds the best to you), and use preouts from the receiver to this amp. Use this amp to power your mains. You will hear the difference.

The speaker crossover frequencies were chosen based on the driver/tweeter parameters, so it is not really recommended to mess with those unless you have a full set of test equipment at home to actually measure the changes. You can obvoiusly upgrade the crossovers with higher quality components (mainly capacitors and resistors, but you can also upgrade the inductors/coils), that will also help with sound quality, but the effect won't be as noticeable as from a stand-alone amplifier.

Erik Tracy

Dr Air wrote: »

I have been enjoying my Polk System for a few years, it was what I bought out of our home renovation funds. I invested in a system that would serve my needs so that I would not have to upgrade to soon. My system consists of the LSI series: LSI 25 fronts, LSI/C, LSI/fx surrounds, and a PSW 505 sub all driven with a Denon AVR 4306. It is powerful enough but it seems that "something" is missing. It is like there is a hole in my listening zone if that makes sense? I have been working with the crossovers and have had some improved response but am not sure what to listen for. Reading some of the veterans' wisdom here makes me realize that I am still a newbie! So, where do I start?

Sometimes the 'hole' can be caused by not having your speakers wired 'in phase' which would mean the speaker cone movement would be opposite to what the sub is doing - basically 'nulling' each other out.

Check your speaker connections - make sure black is to black, red is to red, etc.

The PSW505 also has a phase switch on the back - you may want to experiment and flip it to 180 to see if that fills the 'hole'.

Sometimes the 'hole' can be caused by sub placement where again, due to where the sub is located - its output could be 'nulling' those of your speakers.

If you can try moving the sub around to see if the 'hole' goes away.

Bernal

Hello,
This link may help

http://www.polkaudio.com/forums/showthread.php?t=96827

Bernal wrote: »

①
◊ Main speakers - SMALL - crossover to 60 Hz,
◊ Center - SMALL - crossover to 60 Hz,
◊ Surround - SMALL - crossover to 60 Hz,
◊ Subwoofer - crossover to 60 Hz,
◊ LFE (Low Frequency Effects) channel - crossover to 120Hz.

②
◊ Main speakers - SMALL - crossover to 80 Hz,
◊ Center - SMALL - crossover to 80 Hz,
◊ Surround - SMALL - crossover to 80 Hz,
◊ Subwoofer - crossover to 80 Hz,
◊ LFE (Low Frequency Effects) channel - crossover to 80Hz.

③
◊ Main speakers - SMALL - crossover to 80 Hz,
◊ Center - SMALL - crossover to 100 Hz,
◊ Surround - SMALL - crossover to 80 Hz,
◊ Subwoofer - crossover to 80 Hz,
◊ LFE (Low Frequency Effects) channel - crossover to 120Hz.

④ ⇓-Preference-⇓

◊ Main speakers - LARGE,
◊ Center - SMALL - crossover to 60 Hz,
◊ Surround - SMALL - crossover to 60 Hz,
◊ Subwoofer - crossover to 60 Hz,
◊ LFE (Low Frequency Effects) channel - crossover to 120Hz.


LSi are speakers at 4 ohms. Check processor.

---

01) DENON AVR-4308CI: Advanced 7.1 CH/5.1+2 CH/ 3.1+2+2 CH A/V Home Theater /MultiMedia Multi-Source/Zone Receiver with Networking and WiFi/170 watts x 7 channels
02) SUNFIRE Grand Signature - Bob Carver's
03) OPPO DV-980H 1080p Up-Converting Universal DVD Player with HDMI and 7.1CH Audio
04) OPPO BDP-83 Blu-ray Disc Player w/SACD & DVD-Audio / DENON DVD-2500BTCI: Blu-ray Disc™ DVD/CD Digital Player/Transport
05) HITACHI P55T501. 55" HD1080 Plasma HDTV
06) POLKAUDIO LSiC (Center speaker)
07) POLKAUDIO LSi15 LEFT (Front speaker)
08) POLKAUDIO LSi15 RIGHT (Front speaker)
09) POLKAUDIO LSif/x LEFT (Surround speaker)
10) POLKAUDIO LSif/x RIGHT (Surround speaker)
11) VELODYNE OPTIMUN 12" (High Output Digital EQ SubWoofer 2400W/1200WRMS)

Dr Air

Okay, thank you for the replies. It looks like I have some experimentation ahead. I have tried placement and even did the "put the sub in the listening spot and move around until it sounds best". The polarities are correct, my wire has a red and black conductor so I would not mess up! I know they are 4 ohm; I returned two amps after just opening the box because I was not sure if I had an amp that could easily drive 4 ohm speakers. A call to Polk support put my mind at ease!

Let me offer more information, For the fronts I kept the post bridging in place and am using the standard speaker feeds from the AVR. I was not sure of the bi-amping so I did not do it. I saw a diagram in the Reciever manual where I could use the pre-outs to feed the LSI 25's amp. If I do that I must remove the post bridging, right?

I would like to try the pre-out wiring first; unless, the AVR preouts will not drive the 25's amp. What do you think?