Problems with boomy bass in rehabed speakers

[phileserver39]

Howdy Guys and Gals,

I have a pair of Advent Prodigy speakers which I have totally modified. I replaced the woofers, tweeters and X-overs and am having an issue with harsh sounding highs and boomy bass. Is this something that I can help with acoustic baffling or do I need to take these into a pro and have them adjust the crossover to work with the cabinets? Should I add or remove the baffling to help the bass? I love the heft of these cabs which is why I bought them in the first place. The woofers, tweets and crossovers where all shot but I only paid $20 at a pawn shop for them.

I know that there exists things called L pads (? ha ha) which can help the treble but I am like a mentally challenged school girl when it comes to this kind of stuff. What say you, A.R. experts?

Thanks in advance for sharing your expertise!

Best,

Jason

[Woochifer]

With the bass, another contributory factor is the placement and room acoustics. A lively reflective room will also commonly create a harsh sounding high end. Might want to try changing the location or repositioning the speakers first before you start prescribing wholesale changes to the speakers themselves. Simple stuff like carpeting, strategically placed acoustic panels, or filling a room with furniture and other objects, can have a huge effect on harsh highs. If you get mediocre sound from several different locations, then you can blame the speakers.

[phileserver39]

Thanks for the post and advice Woochifer. Unfortunately placement is confined to a nook/alcove area where the speakers flank a studio-type desk. There is barely enough room on either side of the desk for the speakers, let alone for repositioning. Also, there are windows behind and on the right side of the desk. The windows take up 5/6 of the wall height so I am sure that they are adding to the issue. I might just go back to my ported M-Audio BX-5's and my 0404 interface as I can put the M-Audios on the riser portion of my desk. Plus they are shielded and don't mess with my CRT monitor (yes, I am THAT GUY who still doesn't have a flat panel monitor or TV, ha ha). BTW, I am currently using an X-Fi card to a NAD 3150 amp (acting as a preamp) to a Pioneer VSX-D1S amp (obviously acting as a power amp).


Thanks again for your time.

Best,

Jason

[JoeE SP9]

Do the replacement woofers have the same TS parameters? If not that could help explain the boomy base.

Are the tweeters metal domed? In my experience metal domes have a tendency to sound shrill sometimes accompanied with ringing.

[mlsstl]

Advent had a reputation for well designed speakers. That means all of the components were carefully selected to work together.

You give no indication whether your replacement drivers were real Advent drivers or an attempt was made to match original parameters. Same thing with the crossover. Even replacing the parts with the same value parts is meaningless if the critical values of the new drivers are different.

If drivers were only selected because they physically fit the holes in the cabinet, I'd suspect that is the most likely source of your dissatisfaction with the sound.

[phileserver39]

You are correct in your guess that I chose the components on fit rather than spec. I believe all of the components are Dayton brand btw. I wonder the Frankensteined monsters are even worth trying to get close to original. Thanks for your post, misstl.

[Sir Terrence the Terrible]

phileserver39,
The best way to figure out if the boom is from the speaker itself, or the space you are placing them in is the problem, you just need to take the speakers out of the space and play them. If they no longer sound boomy, then it was the space you put them in that is creating the problem(and that space you are describing is a BIG HUGE problem! If it still sounds boomy when you remove them from the space, then the speakers mods are the problem.

[JoeE SP9]

You are correct in your guess that I chose the components on fit rather than spec. I believe all of the components are Dayton brand btw. I wonder the Frankensteined monsters are even worth trying to get close to original. Thanks for your post, misstl.

I think mlsstl is right. My question about TS (Theile Small) parameters was a polite way of asking what he asked.

[basite]

it might sound crude, but this is why we have speaker designers doing their job.

it sounds like your driver choice is a tad mismatched, and the boomy bass is probably due to the fact that your woofer is not working properly with your cabinet, the TS parameters have to be pretty much the same as the original woofers, and they were custom made for advent...

that, and some inproper room placement...

I think, your best bet (well, the easiest), is to find original drivers...
or, finding better matched woofers, and build your own crossover to a custom job, specifically made for these speakers...

Good luck!
bert.

[Poultrygeist]

You can't substitute one driver for another just because it fits in the same hole. There is so much more that has to be taken into account. Parts Express forum is a good resource to find out what works, what doesn't work and the all important why.

[budgetaudio76]

for the boomy bass try stuffing the cab. Every cubic inch of it.

Either fiberglass or wool would be preferable over poyfiber.
Wool as in sweaters or sheets. At a thrift i found a bag of wool sheets. All folded up. I put one sheet in my tannoy mallorcans. Didnt effect the midrange. And sounds to extend the bass output. You can see what i did in my flickr signature.

[phileserver39]

for the boomy bass try stuffing the cab. Every cubic inch of it.

Either fiberglass or wool would be preferable over poyfiber.
Wool as in sweaters or sheets. At a thrift i found a bag of wool sheets. All folded up. I put one sheet in my tannoy mallorcans. Didnt effect the midrange. And sounds to extend the bass output. You can see what i did in my flickr signature.

Now that is a budget solution....thrifting for wool sheets! ha ha

Thanks Budgetaudio76...cheap and thrifty is very satisfying, isn't it?

Best,

J

[phileserver39]

it might sound crude, but this is why we have speaker designers doing their job.

it sounds like your driver choice is a tad mismatched, and the boomy bass is probably due to the fact that your woofer is not working properly with your cabinet, the TS parameters have to be pretty much the same as the original woofers, and they were custom made for advent...

that, and some inproper room placement...

I think, your best bet (well, the easiest), is to find original drivers...
or, finding better matched woofers, and build your own crossover to a custom job, specifically made for these speakers...

Good luck!
bert.

Thanks Basite- I had a feeling that I was a dumbass when I bought the cabinets in hopes for a "sleepwalk" solution.

I will most likely find drivers that match the cabs rather than great-shape originals. Good advice....

Best,

Jason