Axiom Home Page Forums General Discussion Stereo Subwoofers

I frequently have to change the bass channel level depending on the recording. Some recordings are too hot and some are not hot enough.

I don't know if it's been mentioned but here are a couple of other things you should try. First, try increasing the level of the 60s and turning down the Polk. You may have the Polk set too hot thereby giving you flabby, floppy bass because the higher harmonics don't have enough volume.

I was going to say also try changing the distance of the sub in your receiver but I remembered that you don't have that capability. If it has a variable phase control try varying that. It could be that the timing between the sub and your 60s is off. If the timing isn't right, the fundamental and the overtones will be out of phase and it won't sound tight like it should.

If all else fails, you need to try that sub at someone else's place or bring another sub to your place to see if there's a difference.

Mojo: I've turned down the volume on the sub (it now sits at 10 o'clock), and increased the volume on the main amp. The Line In LPF has been adjusted to 80 degrees. I believe I'm making progress, but it sure is a lot of work. Some of the frustration is gone, and now it's starting to get fun.

If it's any consolation, I spent over 30 hours tweaking my 600. I discovered that I had my 600 tweaked properly within the first half hour but then I kept second-guessing myself.

Mojo: It seems I do the same. I get it to a point where everything sounds pretty good, and I should layoff. However, I always think I can make it better, and invariably, screw up everything.

Can you recommend an audio calibration disk?

Thanks to you and the others who forwarded good ideas to get me going.

Unfortunately I can't recommend one because I don't have one that is "latest and greatest". I've heard of something called Avia...maybe someone with experience on this can comment.

I use a CD that has test tones on it from 1990.

Here is a free download test tone site I used and it seems to work great. If you want to google "test tones" a ton of sites pop up free or pay you can get what you need.

I do have Avia which isn't that great for test tones but the Digital Video Essentials which I also have, has a pretty good speaker test tone array.

I know I'm getting into this way late, but I'm having trouble picturing your setup. So you've got an integrated amp with 5.1 inputs, right? It does no processing whatsoever. So the only processing you're doing is in your SACD/CD player? How many speakers do you have? How is the SACD player hooked up? Does the integrated amp have provisions for crossovers for the main speakers? If so, then it's doing processing. If not, you're in my old condition, where I was actually using tape-outs to supply signal to my sub and using the sub's crossover. Now, I didn't have this setup with really good speakers, but it seemed to work.

I find that a sub can enhance music quite nicely--even with M80s, which have substantial bass of their own.

And yes, there were subs before HT.

Hello and thanks for giving me your views. I have an integrated tube amp (made in China), which plays stereo, and does nothing else. The integrated amp has four I/Ps for CD, SACD, DVD, and tuner, and two pairs of O/Ps to drive the M60's. It also has two pre-amp O/Ps.
I have two M60's, a CD Player and a Polk PSW505 sub which was donated to me.
The M60's plug into the left and right amp O/Ps, the CD Player into the CD I/P, and one of the pre-amp O/Ps to the Sub Line In+ and Line In-.
The sub also has volume and LPF control, LFE, and four Speaker Level O/Ps.
I connect the pre-amp of my integrated amp to the Sub Line In+ and Line In-.
Let me know if you need more info. The booklet the comes with the sub is pathetic.

Hmm. So the only crossover you've got is on the sub itself. What do you currently have that set for? It's harder to blend speakers with sub when that's all you've got; the bass from the speakers has to match the sub pretty well, and the sub has to be pretty fast, otherwise you get a bit muddy. I'd probably set it around 50 or 40 Hz, given the option. Also, does the sub have a phase control and have you played with that?

I agree about using the high level inputs on the sub; mine did not play nicely with that, although it didn't completely fail as yours sounds like it did.

I also experienced the joy of adjusting the volume on the sub/cd, although since you've got it on pre-outs, it won't be so bad for you.

In your testing, it sounds like you were trying to listen to the sub by itself, without the M60s. That's going to sound pretty odd; I'd test with the sub and 60s together and try to match it up that way.

What source material are you testing with? I thought I saw something about pipe organ. While that is undoubtedly a good sub workout, the bass is not necessarily repetitive. I tend to like using Sting--Mercury Falling or Brand New Day to test it out. Those particular albums have bass that you simply won't get through the M60s (I don't get all of it through the M80s, and certainly not nearly all of it through the M50s!), and it's pretty repetitive and constant if you pick the right track. Of course, it may also drive you insane depending on your musical preferences.

I would look at house music or drum n bass if you are looking for repetitive bass!