Need assistance setting up subwoofer (1 Viewer)

[Chmima]

Hi everyone, I'm looking for some assistance setting up my subwoofer; more specifically the crossover cutout frequency. The preset was 100Hz and I changed it to 80Hz because I read that is the best setting for THX. The sub sounds good, I'm just looking to squeeze the best performance out of it I can. Is 80Hz the best frequency for the following setup? Receiver - Pioneer VSX-1022k Sub - BIC Venturi V1020 10" Powered Subwoofer 160W Front Speakers: PolkAudio m20 Center and Sides - Cambridge Soundworks MC300 Rears - Cambridge Soundworks Surround 5.1 Thanks, Christian

 

[Tom Vodhanel]

Hi everyone, I'm looking for some assistance setting up my subwoofer; more specifically the crossover cutout frequency. The preset was 100Hz and I changed it to 80Hz because I read that is the best setting for THX. The sub sounds good, I'm just looking to squeeze the best performance out of it I can. Is 80Hz the best frequency for the following setup? Receiver - Pioneer VSX-1022k Sub - BIC Venturi V1020 10" Powered Subwoofer 160W Front Speakers: PolkAudio m20 Center and Sides - Cambridge Soundworks MC300 Rears - Cambridge Soundworks Surround 5.1 Thanks, Christian

80hz tends to work very well as the crossover for speakers set to small in the speaker setup menu. Couple things keep in mind. 1)In a DD/DTS surround system the subwoofer (assuming you indicate you have a subwoofer in the receiver's setup menu)will always receive the full LFE channel (the "point 1" in a 5.1 label). The LFE bandwidth is 3hz to 120hz and is "brick walled" That is, no shallow sloping here....at 121hz.....no signal.. Some newer receivers offer the ability to change the upper frequency limit of this channel but I don't see any benefit here. Just leave this setting at 120hz if you find it buried in the receiver menu. 2)The crossover point commonly adjusted (as in the original post) affects the bass "cutoff" of your speakers. If you select 100hz, your main speakers will product everything above 100hz unfiltered. Starting at 100hz the signal going to your speakers will gradually be attenuated. The bass from 100hz and down (that is being filtered away from the main speaker) will be electrically rerouted in the receiver's bass management section, combined with the LFE channel...and sent to the subwoofer. Remember that placement of the subwoofer can make a big difference on how it performs in a room. Corners work well, particularly corners near the key seating. There is also the "sub crawl" (google it..). Next, get the bass levels calibrated either using an "auto setup routine" in the receiver or manually with a SPL meter. If you set the bass levels by "ear" chances are they will be way high. Also, experiment a bit with the phase control to ensure the best "blend" between the main speakers and the subwoofer. Tom V.

 

[Jim Mcc]

Doesn't it depend mainly on the low end of his speakers?

 

[Tom Vodhanel]

Doesn't it depend mainly on the low end of his speakers?

Yes, to some extent. (no pun intended!) I checked his mains and they are rated to 45hz. Even if that's optimistic as many "specs" are....I'd say 80hz would still be quite safe. At that point(knowing you mains can handle 80hz or 100hz highpass points) the easiest way to determine which works best is simply to experiment. Some subwoofers don't really like extending up to 100hz, others run out to 200hz and above with no issue. Also, the room acoustics will play a role. The mains may be in a location that causes a room induced response hiccup at the seating positions in the 80-100hz range. The subwoofer will (hopefully) be located to ensure the best/smoothest bass performance at the seats. In my experiences 80hz almost always works best(assuming your speakers extend down to at least 80hz without straining). But opinions do vary. Tom V.

 

[schan1269]

^^^ Speaking of which, I just discovered a pair of Optimus/RCA PRO-LX55(40-5037) speakers that came with a lot of stuff I bought... The woofer surrounds were rotted, so I replaced the surrounds...and boy do these things sound good(I had a large set of Lineaum speakers ages ago). Supposedly these things reach 80hz...but they sound so much better at 150. Tempted to use them as my computer speakers in replacement of a pair of Polk RM Monitors. In any case...just because a speaker "can produce" to a certain frequency...doesn't mean you are going to like it.