Axiom Home Page Forums General Discussion Home Theater HSU STF-2 & CompUSA

I'm not sure why the gain controls on Hsu subs are so touchy, but my VTF-2 rarely is turned as far as 9 O'clock. If it's thunderous and clean at the setting you've got it now, it sounds like you've got it right. There's just never a need to crank that gain knob up too high. A little bit goes a long way.

To properly calibrate a sub (and all the other speakers in a home theater setup), you really need a sound pressure meter. 9 o'clock, 10 o'clock, halfway up, etc., are totally meaningless without a reference.

It seems to me you actually turned down the overall volume of the sub. You really need to get an SPL meter and calibrate properly. I suspect you have the sub too "hot" or loud.

With the rumble you hear on those scenes, or other scenes, what is the volume like on the rest of the system?

By using the gain control on the sub, you should try to get the receiver to just a few db above zero on the sub volume.

Bottoming out happens when the excursion of the driver exceeds the limit and hits the structure behind it.

Get a SPL meter and correctly set all of the speaker levels including the sub. That "clack" shouldn't happen if you have the sub properly calibrated relative to the other channels.

K. Looking to get an SPL meter. The further you get into this hobby (first "real" speakers... first "real" sub...) the more $$$ it takes!! Love it!

I did not feel that I had the overall sound on the other speakers too loud during the scenes where the driver "clacked". I must have just had the sub specific settings too hot. Even though they were soo very low on the dial.

It just amazes me how clear / loud this axiom/HSU combo gets with little movement on the volume dial. And I have a low power amp behind it all. Unreal!

Well said, Tony G. This is the essence of calibration. Dial positions, dB readings on your amps, etc., aren't linear and the relationships aren't standardized. It's all relative. 5000 RPM in top gear in a Civic is not equivalent to 5000 RPM top gear in a Viper, right? The bottom line is: how fast, how loud, how long, how high, in relation to a standard. Buying a sound level meter and a decent calibration disc is a sound investment. If you have any questions, search old posts or ask questions here; you'll get helpful, INFORMED answers. Even when it gets heated or cranky, this is, in my experience, the best forum, bar none.

I didn't mean to imply that Hsu subs settings should be under 9 o'clock or anything like that. I have my speaker and sub levels calibrated using my handy RS meter. But as I said, properly set, the gain control on my VTF-2 is barely turned up at all. That was my point.

Barring a couple recent threads, it rarely gets cranky around here. I used to visit several other boards regularly, and nothing compares with the great crowd of guys we have here.

"Buying a sound level meter and a decent calibration disc is a sound investment."

Intersting way of putting it.