DETERMINING SPEAKER SIZE

[BigStewMan]

What determines speaker size in regards to amp settings?

I have the complete F3 system w/ ksw12 sub--should the settings be large or small?

[marems]

I have read that if you have speakers with an 8" driver or bigger then set to large. The F-3's should sound the best set to large.

[DrWho]

In your case, I'd say the one that sounds better to you. If your subwoofer was more potent, then I'd say set everything to small.

The large/small setting just determines wether or not frequencies below the crossover point should be sent to that speaker. You might find this article helpful:
Dial in a sub by Ear

[BigStewMan]

nice article doc, thanks. perhaps you should consider a "road show" where you can pass on more of your knowledge. or are you afraid we'll start calling you professor?

[DrWho]

lol thanks. But in all honesty, I can only be credited with regurgitating the info that has been passed down to me. You can call me professor after I invent a speaker with khorn performance in a package the size of a Bose cube []

[sredmyer]

Really good question.

I am not familiar with your speakers but here is my .02

I see alot of folks recommending that the mains should be set to small and crossed at 80hz even when the mains are obviously capable of doing some pretty good bass. It just seems to me to be a waste of speaker to only send frequency above 80hz to large speakers. I think if your mains will go deep and you have enough amp to drive them there, set them as large and just let the sub help them...not do their job. However if your speakers -3db point is much higher or your amp/receiver doesn't have enough current (notice I did not say watts here) then set the speakers to small and let the sub do the job.

I have Ref 7 family 5.1 system with RSW-12 sub and I never can figure out what is best based on what I hear others say but here is how mine is setup (and the logic for doing it that way). I think the RF-7s are rated at -3db @ 32hz and I think the sub is rated at 22hz so since they are so close in that regard I figured I should set my RF-7s to large and send them the full bandwidth signal. The RC-7 is rated -3db @ 45hz so I set it to small and cross it over at 60hz. The RS-7s are rated -3db at 58hz so they are also set to small and crossed over at 80hz. Then I set my sub crossover to 60hz and the bass management to L/R+LFE. I do not do much movie watching, the system is primarily used for 2 channel (+ sub) audio. I have no idea if this is an optimal setup but it sounds good to me (course I have been accused of having pretty tinny ears []).

[sredmyer]

lol thanks. But in all honesty, I can only be credited with regurgitating the info that has been passed down to me. You can call me professor after I invent a speaker with khorn performance in a package the size of a Bose cube []

If you do that I will call you god (well maybe just god-like) []

[Islander]

Two weeks ago, I relocated my system so the Scalas are on the long wall and much further apart than they had been, thanks to a tip from Peter (thanks, psg) and the sound was quite improved. However, the surround speakers were no longer where they needed to be, so I moved two of them for now, and ran Yamaha's YPAO auto setup routine. It declared that the La Scalas were small and out of phase with the other speakers.

Actually, the only things the YPAO got correct were the size and distances of the surround speakers. All the other distances were off a little, and the sub was about 4 feet closer than indicated. Interestingly, though, I learned that the Scala distance to the listening position should be measured from the back of the squawker horn, at the driver, not at the front of the horn. Obvious when you think of it, but not like cone speaker enclosures.

According to the owner's manual, the program is not always correct about phase with certain speakers. As for "size", the La Scalas are certainly big, but their gradual bass roll-off might make them test like small speakers. However, having the low bass coming from the two Scala bass bins (even with it tapering off below 100Hz or so) plus from the sub makes for a noticeably fuller sound, so I set mains at "large" on the receiver.

Accordingly, I agree that main speakers capable of any decent bass response should call for the amp settings to be set at "large" for the mains. Just my opinion.

[bhenry]

This is what it is all about: What sounds good to you.

Set your speakers to large and play with your sub and crossover settings, then do the same with the speakers set to small. Which sound do you prefer, it's YOUR system!

FYI: My B&K Ref 50 is set to small speaker size (all 5 channels) with the crossover set @ 80.0 Hz

High Pass Slope: 12.0 db

Low Pass Slope: 12.0 db

LFE Level: 0.0 db

Crossover on subwoofer on bypass, volume knob slightly under 1/2 way up.

Main Seakers: RF 7's Center: RC 7 Rears: RF 3II's Sub: RSW 15

I let the sub do the lower frequencies because I think it sounds alot cleaner, even though my RF 7's are perfectly capable of reproducing them.

Correct me somebody if I am wrong but room size and layout contributes to this equation also.

[colterphoto1]

For RF7 and similar full range mains (Chorus, CW, KLF30), I'd try it both ways and listen for yourself.

LS roll off around 80, pretty serious drop after 50. I set mine to SMALL a while back and it made a world of difference. Again, it's not the cabinet size, it's whether or not the speaker is truly FULL RANGE. If it can reproduce anywhere close to 25 Hz fairly flat, I'd call it LARGE, but few speakers can do this accurately.

Better to let the Sub take the duties of not only the LFE, but whatever happens in the other channels below 80 Hz. It has the power, excursion, and the cabinet design to do so. And it's quite a load off of your other speakers, which protects them and cleans up their sound significantly.

Using the THX suggested 80 Hz crossover sends only two of ten audible octaves to the Sub anyway. (20-40=1, 40-80=2).