Rerurn to Romy the Cat's Site

Playback Listening
Topic: ULF: where is the borderline....?

Page 1 of 1 (5 items)


Posted by Romy the Cat on 07-16-2021
You have a nice very much full-range, preferably multichannel, playback system, and you like what it does. Now, disconnect your very lowest channel. Disconnect it and get use to this sound. Then put the lowest channel back to rotation. You got better sound all together. However, admit to yourself that “something” got worse. How do you deal with it?

Posted by Paul S on 07-16-2021
Romy, is this a trick question? You are the only person I know of with time aligned, true IB ULF channels using 4 Aurasound sub-woofers, so who's going to answer your question?  The first thought that came to my mind was how some "Big Music" composers let some musical lines be "carried on the ULF", like the ULF is buoying it along. I have observed that not having proper ULF slights this effect. But I don't have effective ULF in the first place to know what problems it causes. I know that one "needs" a balance of HF and LF; but you also have the spectacular RAAL ribbons...? One thing is to be sure perceived problems do not inhere in the recording. Of course, "phase" is always an issue at ULF...


Best regards,
Paul S

Posted by Paul S on 07-17-2021
I forget if you started out by setting the phase and level(s) of your ULF with DSP to begin with. Not to cave in to herd mentality, but it might be "worth it" to rent a DSP/D (servo) amp(s) combo to play with. If nothing else, that amp has to modulate something like 2 1/2 pounds per channel (driver mms), not to mention dealing with the back EMF from something like 60 lbs. of magnets!

Paul S

Posted by rowuk on 07-23-2021
The frequency where your room turns into a pressure chamber changes the way that we perceive bass. This is how we get "bass" in a too small space like an automobile. When removing the ULF channel, all of the music is transmitted in a natural way for our ears to process. Adding the ULF channel back usually shows the hard knee of the switch between radiation and pressurization. Wavelengths too long for the space fold back.
How I deal with it? Open doors, windows etc until I get used to it again.

Posted by noviygera on 08-02-2021
I would try reducing the level of lowest channel or only play left or right side (if stereo ULF). Then run your experiment again.

Page 1 of 1 (5 items)