Fill Rear Port Hole to help improve bass - Monitor 30's

27dnast

Just pulled the trigger and bought some Monitor 30's for surrounds. One of the reviews I read said the speaker can be a bit boomy when wall mounted. The reviewer mentioned that someone had recommended he stuff the rear bass port hole with a sock and that it would eliminate the boominess.

This reviewer filled the port holes with foam... and said that it made the bass much tighter and more controlled --- indicating that it was a big improvement and made the speaker sound better.

Has anyone ever tried this or heard of this being tried?

intangible

Plugging the port represents a pretty drastic change in the character of the cabinet. It would definitely attenuate the bass. Socks are cheap, so you might as well try it for yourself and decide if you think it is an improvement.

thetawave2

I'd try it with the socks first. Best case scenario, you like the results so much you upgrade to foam. Worst case scenario you hate the change and take the socks out of the speakers and wear them instead.

Erik Tracy

27dnast wrote: »

Just pulled the trigger and bought some Monitor 30's for surrounds. One of the reviews I read said the speaker can be a bit boomy when wall mounted. The reviewer mentioned that someone had recommended he stuff the rear bass port hole with a sock and that it would eliminate the boominess.

This reviewer filled the port holes with foam... and said that it made the bass much tighter and more controlled --- indicating that it was a big improvement and made the speaker sound better.

Has anyone ever tried this or heard of this being tried?

Are you using the Monitor 30s in conjunction with a sub and an AVR using bass management?

If so, and you set the Monitors to 'small' then you are low pass limiting the bass to the Monitors which should cut down on any boominess with them being close to the wall.

Plugging the port would be something to try if you are not using any bass management.

27dnast

Erik-

Yes, the 7.1 set-up will powered by a pioneer elite avr... crossover set at 80Hz.

I'm planning on setting my RTI4's (front mains) the csi A4 center and all of my surrounds (the Monitor 30's are the L/R surround and two RM6750's are the rear surrounds) to small. I have a 12" Energy sub that will handle the bass.

Also, I'll use the MCACC on the elite avr to dial in the speakers.

Does this sound about right?

Erik Tracy

27dnast wrote: »

Erik-

Yes, the 7.1 set-up will powered by a pioneer elite avr... crossover set at 80Hz.

I'm planning on setting my RTI4's (front mains) the csi A4 center and all of my surrounds (the Monitor 30's are the L/R surround and two RM6750's are the rear surrounds) to small. I have a 12" Energy sub that will handle the bass.

Also, I'll use the MCACC on the elite avr to dial in the speakers.

Does this sound about right?

Then I'd give this some time to listen to before you decide to plug any ports.

If, after some time, you still think the bass from the Monitors sounds tubby or bloated, then you could try plugging the ports, but with a sub and with the AVR bass management, I don't think you've got anything to worry about.

27dnast

I agree... need to hear it first (which will require this new gear to get here!).

I had never heard of plugging a bass port... so I just wanted to float the idea. Never know when you are going to learn something new!

Thanks for the input

The Monitor 30's were so cheap... I'm trying to justify (in my head) that I can always make a modification to improve sound so the speakers can fit in my preferred layout. That being said, I'm hoping the 30's prove to be surprisingly dazzling.

EndersShadow

I had Monitor 40's wallmounted and at no point felt they were "boomy". I now have Infinity Primus 162's wallmounted and like them better, but that has more to do with how they look and fit into the wallmounts.

I think you will find you wont need to plug the port at all once you install them.

Erik Tracy

27dnast wrote: »

I agree... need to hear it first (which will require this new gear to get here!).

I had never heard of plugging a bass port... so I just wanted to float the idea. Never know when you are going to learn something new!

Thanks for the input

The Monitor 30's were so cheap... I'm trying to justify (in my head) that I can always make a modification to improve sound so the speakers can fit in my preferred layout. That being said, I'm hoping the 30's prove to be surprisingly dazzling.

I have the ports on my B&W speakers plugged because they are wall mounted and I do more 2-channel listening than movie watching.

Because my 2-channel setup has no bass management, and I still use a sub with 2-channel listening, the port plugs act as a type of 'bass management' (steep cut off of bass coming from the ports) which allowed me to better integrate the sub and my speakers for cleaner bass.

With active bass management with an AVR, you wouldn't need (imo) to worry about port plugs.

rebuy

I remember shopping for speakers years ago and one manufacturer made a big foam plug to plug the port hole if you so desired. I can't remember who made that speaker but it was an option.

mrbigbluelight

The advice to set the Monitor 30's to "small" should do the trick.
The Monitor 30's are absolutely perfect, IMO, when used as rear surrounds for HT. Impossible to get a better price/performance ratio, IMO.

Geoff4rfc

mrbigbluelight wrote: »

The Monitor 30's are absolutely perfect, IMO, when used as rear surrounds for HT. Impossible to get a better price/performance ratio, IMO.

27dnast wrote: »

The Monitor 30's were so cheap... I'm trying to justify (in my head) that I can always make a modification to improve sound so the speakers can fit in my preferred layout. That being said, I'm hoping the 30's prove to be surprisingly dazzling.

My 30's have been in the surround position and sound really great. I can't imagine what they'd sound like as mains.

cnh

Foam plugs are common with some bookshelves...and give you an option. But in my experience you're 'better' off playing with positioning in the room to adjust your bass because a lot of the time plugging up the port may tighten the bass but you also lose a LOT of low end there?

Spend some time with room boundaries--moving the M30s around and you'll find they're much less boomy.

cnh

27dnast

I actually have the M30s in possession, but am not going to use them. They never made it out of the box. I'm hoping to sell them to someone on the board... if not, they'll get returned. That being said, thanks for the insightful input... all adds to the database of facts in my head!!

27

Geoff4rfc

27dnast wrote: »

I actually have the M30s in possession, but am not going to use them. They never made it out of the box. I'm hoping to sell them to someone on the board... if not, they'll get returned. That being said, thanks for the insightful input... all adds to the database of facts in my head!!

27

Any new plans, which speaker choice next?

Outfitter03

27dnast wrote: »

I actually have the M30s in possession, but am not going to use them. They never made it out of the box. I'm hoping to sell them to someone on the board... if not, they'll get returned. That being said, thanks for the insightful input... all adds to the database of facts in my head!!

27

This post is confusing to me 27dnast. It sounds as if you are having buyers remorse solely from reading opinions on these speakers and in spite of several favorable reviews in your own thread, won't even listen to the speakers that are at your house.

I cannot imagine getting new audio gear to my house and not even trying it unless I found out that it physically would not fit or it was damaged in shipping. Maybe you can explain a little better what you are trying to do.

Mon40CSMM10

EndersShadow wrote: »

I had Monitor 40's wallmounted and at no point felt they were "boomy". I now have Infinity Primus 162's wallmounted and like them better, but that has more to do with how they look and fit into the wallmounts.

I think you will find you wont need to plug the port at all once you install them.

I know I'm in a 16 feet wide by 9.5 feet deep by 7.5 feet high apartment living room setting (glass door on the left, open to the other rooms on the right), but even when they were not wall mounted, I found Monitor 40's to be either bass starved or boomy even at distances as far as 2 feet away from the wall. This is when the speakers were set to Large, or even when set to Small if I used a 50 Hz or 80 Hz receiver crossover. I've actually had to use a crossover as high as 150 to get a good sounding blend where I could turn it up a bit and not overwhelming the room with deep bass. However, higher crossovers started to sound bass starved, so then I also had to compensate by moving the Monitor 40's unitl the back of the speaker was as close as 6 inches from the wall.

(Now, this was only an issue because it's an apartment living room, but I am more than impressed with how much bass those rear-ported dual 5 1/4 inch woofers can output, running frequency tests showed they can generate bass down to 30 Hz.)

Plugging the ports starved the bass even more when the speakers were set to Small, but the bass was still quite boomy when set to Large (it just got muddier).

What worked for me eventually is to use one of those car audio passive crossovers ("bass blocker"), but with the receiver crossover set to 80 Hz and the speakers set to Small. The bass blocker is supposed to attenuate 200 Hz at 4 ohms and 100 Hz at 8 ohms.

I'm also trying the Monitor 40's at a distance of about 22 1/2 inches away from the wall with the bass blocker installed, the speakers set to small, and the crossover at 80 Hz. If that works then I'll leave the Monitor 40's as mains once again instead of the replacement M10's. Otherwise, I go back to the M10's and I'll also set the M10's to Large because M10's set to small does not allow the speaker to generate its full potential of sound.

BeefJerky

I don't know why, but this thread reminded me of this classic:
http://www.polkaudio.com/forums/showthread.php?p=491981