La Scala's bass question?????

[playntheblues]

Hi all, I am in between speakers right now and I have moved my La Scala's up to the main listening room from my music studio for now. They have Bob C's tweeters and AA XO that has been cryoed. At low volumes they sound great but as I turn the volume up (now this might ruffle some feathers, I hope not) the bass just gets nastie, boomie etc. From 400 htz and up they sound great, but I really can't take the bass at all, at volume that is.

Is there an easy fix here or not? I have heard of folks putting bracing in the bass horn and although it helps some have heard it's not a big help. Open to ideas?

Thanks, Guy

[playntheblues]

I thought I might ad.............I don't mind adding a sub for the lower octives if I can just get the bass to 50 htz to firm up.

[Don Richard]

Try checking the tightness of the bolts holding the woofers. While doing that, check the gasket on the access door. Air leaks can ruin the bass on a horn loaded woofer such as the LaScala's. Years ago I bought a pair of LS that had been used as a PA in a church, and found this to be a problem with them. It may be wise to do this on an annual basis if you play your system loudly, regardless of loudspeaker type.

[playntheblues]

Thanks Don I will check that today as these speakers where used in the DJ business before I bought them4 years ago.

[Chris A]

Could you describe the dimensions of the room in which the LSs presently reside, i.e., the length, width, height, speaker locations, listening positions, and floor covering type? A hand-drawn plan view of the room works great.

[Guest " "]

Gentle sloping xovers such as AA's are great for conservative listen levels....but depending on what you mean by cranking it up, you might need to move to steeper sloping xovers.

The sub approach is a good idea since LaScala's do not have a low reach to start with.

[playntheblues]

I checked the seals and woofers, both are fine. The room is 17' X 27' the speakers are on the short wall about 6' from the rear wall. There is a stair way behind the speakers hence the distance behind them. Also a sub would be fine if we could tighten up the bass.

[Duke Spinner]

that's an odd complaint, boomy bass from LaScala ..

check the room modes

[EL34]

As firitz has indicated, they really don't have low bass output and if that is what you want, you need to add subs. A pair of CV scoops and an electronic x-over would be most impressive... and deafening ;-).

-Bill

[Chris A]

...The room is 17' X 27' the speakers are on the short wall about 6' from the rear wall. There is a stair way behind the speakers hence the distance behind them. Also a sub would be fine if we could tighten up the bass.

I noticed that you didn't mention the ceiling height, where you sit to listen to them or the floor covering. I would recommend moving the LSs around - closer to a wall, and/or move your listening position. The problem with adding subs is that it probably won't help the boominess. I assume that you had Khorns or something similar in the room earlier. If they were in the same locations as the LSs and you didn't have issues with the earlier speakers, then you are probably exciting one or more room modes close to the rise in response of the LS bottom ends. In my limited experience, LSs are not generally known for booming bass unless they are in a less-than-optimum room position.

IMHO, once the booming bass issue is solved then I would address the lower end using one or more subs since LSs start rolling off at about 55-60 Hz (anechoically). Bigger effective subwoofer cone areas/more drivers will be better matches for the LSs, which have significantly lower distortion relative to direct radiating loudspeakers.

Chris

[IndyKlipschFan]

I could reccomend the THX series amp and subs... He might drool though....

[Islander]

Bigger effective subwoofer cone areas/more drivers will be better matches for the LSs, which have significantly lower distortion relative to direct radiating loudspeakers

Could it be that a smaller sub driver with a bigger amp might be more able to keep up with the speed of La Scala bass?

[IndyKlipschFan]

Islander re read my post .... And my profile.

Yes, is the short version to your question.

[geneylim]

Try lifting the speakers 4 to 6 inches.

[Marvel]

Try lifting the speakers 4 to 6 inches.

20 times with each arm...

[Chris A]

"Anything that moves, distorts." (attrib. PWK)

I believe that the idea is to spread out the lf load to more than one sub to keep distortion to a minimum by requiring less displacement, unless, of course low distortion is not a goal...

[Chris A]

Bigger effective subwoofer cone areas/more drivers will be better matches for the LSs, which have significantly lower distortion relative to direct radiating loudspeakers

Could it be that a smaller sub driver with a bigger amp might be more able to keep up with the speed of La Scala bass?

"Speed?" Are you referring to build-up or impulse response of the sub, which has to move proportionally longer throws for smaller cone areas to achieve higher output? I believe that we are talking distortion again.

Otherwise, Mr. Fourier I think has the upper hand in this conversation, unless you are trying to extend the upper frequency of the sub, for whatever reason.

[playntheblues]

WOW, a lot of comments to respond to. Ok the floor is carpet, speakers are 9' apart listening seat is about 11' from speakers, speakers are 7' from back wall due to stairwell. I will try lifting the speakers 6 inches and see what happens.

[Islander]

]"Speed?" Are you referring to build-up or impulse response of the sub, which has to move proportionally longer throws for smaller cone areas to achieve higher output? I believe that we are talking distortion again.

I was referring to the ability (or lack of it) of some subs to match the transient (or impulse) response of the LS bass bin, which some subs are said to have difficulty with.

As for distortion, the low bass region is the least critical in that regard. My father was a professional musician for a number of years, and he told me that when he was playing the string bass that most listeners could not even tell whether he was playing in tune or not. Distortion from tweeters is easy to hear, from woofers not so easy, and from subwoofers fairly difficult. Put your ear to the grille of a sub and see if you can pick out any distortion. I sure can't.

When the string of a bass instrument is plucked (if it has strings, of course), most of the "pluck" sound is in the mid-bass or higher and doesn't come from the sub at all. The deep resonances of the instrument may come out of the sub, but if the pitch and impulse response are faithful to the sound of the live instrument, a little distortion from the sub will not be bothersome or even audible in most cases.

[djk]

"he told me that when he was playing the string bass that most listeners could not even tell whether he was playing in tune or not. "

The players themselves can't tell if they are in tune or not.

I used to watch bass players plug into the strobe tuner, tune it up, then plug into their bass amps and 'fine' tune it. It would be in tune until they started in on the 'fine' tuning, then you would hear it start to go ***-***-*** (beats) as they de-tuned it. Being in the near field pressure zone tightens up their eardrums and distorts the pitch they hear. Being in the free field (audience) all I could do was cringe!