younggun

home audio help.

hey guys, first post here.
i am having a small, but very irritating problem with my home sound system.

first of all, the setup is a Denon usrround reviever AVR-1505, paradigm Monitor 7v.4 towers, with rear cinema 70 v.2 speakers(paradigm) and a paradigm cc-170 v.3 center mounted speaker.
along with that i have a Paradigm PDR-10 v.3 sub. thats whats giving me problems.
some movies, and espcially with music it sounds like its bottoming out very bad. it sounds like crap!

i cant get the reciever over -25 without it making the noise. i have the sub settings on the rear turned down low, and even the DB levels on the reciever turned low.
i like to listen to my music loud, and i tend to listen to tunes with a fair bit of bass.
any input?

Thanks in Advance!
Marshall

Robert_J

Re: home audio help.

First calibrate everythign with a Radio Shack SPL meter. It's the best $40 investment that a home theater enthusiast can make. A calibration DVD with the SPL meter is even better since receiver test tones have been known to be off.

If that doesn't solve your problem, you need to plot the frequency response of your sub. Again, using the SPL meter and a CD of test tones. The software to generate the tones is free. All you have to do is burn them onto a CD. Based on the results, you may need to move your sub around to another location so that there are less peaks or nulls in your listening position. Sometimes an EQ is required to flatten the response. Details on all of this will require multiple postings so lets wait until we get to this point.

Finally, you may not have enough sub to meat your bass goals. You are just pushing it past the limits every time you listen. Sooner or later, it will give up if you keep bottoming it out. Do you hear a metal to metal CLACK? Or is it just heavy distortion? Distortion could be anything from amp distortion to pushing the driver past its linear limits but not mechanical limits. Bottoming out is pushing the driver until the voice coil smacks into the back plate of the magnet. If this is the case, an additional sub of the same model or replace it with a more capable sub.

-Robert

younggun

Re: home audio help.

definately bottoming out.
sounds like its hitting something.
i guess i wil get a meter and see if i can get it set up right then how everything sounds.

Thanks a tonne!
Marshall

younggun

Re: home audio help.

so i went out and bought a scosche SPL1000
i hope it was the right one.
i put on a couple bass testers and looked at the chart and set the sub to the DB level it says, and then turned it up to where it bottomed out, then back down, and i have it set fairl good.
doesnt bottom out anymore on hard bass hits, or constant low freq.

i also re-positioned my sub so the sound come out toward the viewer, it was mounted going sideways before. if that makes sense.

one problem that irriates me is when the volume is turned down for watching movies, the bass isnt very noticable anymore because i have it set for a higher volume level.

Robert_J

Re: home audio help.

The Radio Shack SPL meter is the prefered budget meter at about $40. It has a known frequency response and correction values are widely available.

That is not the proper method of calibration. Your receiver should have a setting where it outputs tones to individual speakers. You use the SPL meter to adjust the settings on each speaker so they are all the same level. But receiver tones have known to be off a little so we recommend using a DVD like Avia or Video Essentials. They also have calibration tests for your TV as well so it is like a bonus.

Bass is non-directional. Changing the orientation of the sub would not do anything. Moving the sub to different locations in the room will. The best method is to play the sub in the listening positon and crawl around the room with the SPL meter until you read the highest level. That is were the sub goes. Use test tones at a low to moderate level during this.

A sub should not be noticed. It should blend in seamlessly with the rest of the speakers. I run a pair of 15" subs powered by a 2,400w professional amp and they are barely working during 99% of my listening.

-Robert

younggun

Re: home audio help.

i couldnt find the radioshack SPL meter.
all of our radioshck's are now curcuit city, and they didnt have what i was looking for.

i guess i have to get a proper SPL meter and do it correcty. is it worth paying someone to calibrate your system? this is my first experince with anything like this...

i did reposition my sub within the room. not just turn it.

thanks alot for the help so far!

Robert_J

Re: home audio help.

$44 from SVS. I'll bet Fleabay has a ton as well.

Is it worth it to pay someone hundreds of dollars to come and calibrate your system? I don't know how you throw your money around but I'm pretty thrifty. It did take some time to learn how to calibrate so is your time worth that much? I use occaisions like that as a learning experience. In the future, it will save you money. You will buy new equipment and have to re-calibrate. If you don't know how to do it, then you have to pay someone again.

It doesn't apply directly here but here is how DIY saves you money. I learned how to install satellite dishes back on my first system. Since then, I have installed at least a dozen dishes for friends, family and the different places I have lived. On my last upgrade, DirecTV required a "professional" install of the dish. Fine. It was free. Well, I got what I paid for. Within a few months, wind had blown the dish out of alignment. I called D* and asked for a re-alignment. $97 for the service call is how they responded. I argued, pleaded and begged. They didn't budge. The next morning, I pulled out my ladder and adjusted the dish myself. It took less than 10 minutes and saved me almost $100.

-Robert