Hello,

I have been a very hapy owner of a mostly Axiom setup for a few months now.

I am currently running two M22 fronts, VP 100 center and 2 M2 surrounds with my old hand me down Velodyne 8" sub.

Now , I love almost every aspect of my system, except that on music and film scores (while watching dvd/hd-dvd) I have noticed a severe lack of high bass. There seems to be some weekness in the bass lines, but only at the higher ends.

My velodne does fine with explosions and those really low bass notes, but inbetween the low bass and where the mid range on the M22's picks up there is clearly something lacking.

I had originally inteneded on my next upgrade being a new subwoofer, but now I'm not sure that is my problem. Is this the fault of my old sub, or the M22's? Should I be looking at upgrading to M60's and living with the sub, since it seems to handle the extreme lows very well?

Or, am I being stupid and this is a crossover issue. I currently have the crossover at 80, but should I push that up to 100 and let the sub do more of the work?

Any thoughts on the topic would be greatly appreciated.

You should be looking into replacing the sub. That is where the shortfall in your system is. How big is the room and what is your budget?

I'm looking to only spend about $500-$600, because I also intend on buying the new sherwood HDMI 1.3 receiever when it comes out this summer, and that will probably blow my budget. I could wait a little longer though and save closer to $800-1k if it was worth it, because I currently live in an apartment where unrestrained sub isn't usually possible.

I plan on moving before next fall into a place where the sub will be allowed to "roam freely" so to speak, so I do want something more "capable" in the long run. So, I could live with what I have until I move and save for something better if the $500 range won't be a significant upgrade.

Oh, and the current room is 18x12 plain old rectangle. We sit about 8' away from the tv. Sub is in a front right placement.

With a budget of 5 to 6 hundred I would take a serious look at Hsu subs. The VTF 2.3 or the STF 3 is within your price range and both would be a very significant improvement over your existing sub. You could also look at SVS .

I know this music...

See here.

Get a better sub. I had the same 'issue' with my m22's + crappy kenwood sub that you describe. I bet something from the HSU STF series or an SVS PCI 25-31 would go a long ways towards fixing your problem and be in your budget. I spent *months* tinkering with placement and crossover settings. I now know that my old sub just didn't have much in the way of upper bass frequency response. Your Velodyne is a better sub than my Kenwood, so I'd say it's worth tinkering with the crossover settings - but in the end a new sub may be the answer.

You could look into getting the new Mid-Bass unit from HSU. It's specifically designed to bring up the upper bass in your system.

You could also play with room acoustics. Not nearly as much fun as toys, I know. I recently suggested to my wife that she buy new heavier-fabric drapes for our den. They warmed up the room and bumped up the overall warmth of my system just a bit. She got new drapes + I got better sound = everyone's happy. A win-win.

I replaced my Kenwood with an SVS PCI+ 20-39 and it went a long way towards fixing the problem. Didn't solve it completely for me, but the overall sound quality was significantly improved. I like my speakers a little bit on the warmer side (I like the way B&W's sound, for instance), and even the m22+SVS setup was still a bit 'cool' in the lower midrange for me.

Of course *THAT* started another round of severe upgradeitis that I'm finally just now getting under control, so be really careful once you start ordering new stuff.

Is the crossover on the sub itself bypassed?

Pardon my newbie ignorance, but how would you bypass the crossover on the Sub.

My receiver's crossover is set at 80Hz. I had read somewhere to put the sub crossover a bit higher so it will be sure to pick up all of the signaal the receiver sends tto the sub. So I have the sub crossover at 110-120. Is this incorrect?

Remember that a crossover is not a hard cutoff, but a slope, so both your sub and your mains will play sounds at and around the crossover frequency. Because of this it's important to ensure the sub and mains are playing in-phase.

If the Velodyne has a phase switch or phase dial, change its position and see if it improves anything.

The Velodyn has a switch. Norm/Rev. Right now it is on Norm. If I switch to rev, what would that do?

It would make the driver on the sub 180 degrees out of phase of the M22 drivers. Try it it won't hurt anything.

Higher-end subs usually have a switch that disables the sub's internal crossover network completely - it's usually labeled 'BYPASS'. It sounds like your receiver is doing the crossovers, and that's the correct way to do it. Your sub then should not perform any crossover actions itself. This is when you would want to flip the BYPASS switch, or if you don't have one, set the crossover dial on the sub to as high a frequency as it will go to seperate the crossovers as far as possible.

The problem occurs if both your receiver and your sub are set to similar crossover frequencies, as you'll get overlapping crossovers that can do weird things to the sound quality, i.e. a mid-bass hole. If you can turn the subs crossover higher than 110-120, do it.

Tinkering with the phase switch probably won't help, but it won't hurt anything either. Don't be surprised if you can't hear any difference between 0 and 180.

Quote:

---

Pardon my newbie ignorance, but how would you bypass the crossover on the Sub.

My receiver's crossover is set at 80Hz. I had read somewhere to put the sub crossover a bit higher so it will be sure to pick up all of the signaal the receiver sends tto the sub. So I have the sub crossover at 110-120. Is this incorrect?

---