Making Vantage Sealed Box (Port Plug) Question

[Pars]

I am planning to try to plug the port of Martin Logan Vantage, or even cutting a wood and screw it over the port. First of all, did anyone tried this? Normally the low end must go and thighter bass should come. with conventional systems. Is it the same? Does it hurt the system? Including the amp inside and woofer?

Thank you

 

[Robert D]

I've seen ported subwoofers marketed with plugs. I think SVS might be one brand that does that.

 

[Russr]

The functional design of a bass enclosure is typically built to support a very specific "tune". Some others with more brain cells than I can probably provide details in terms of octaves, dBs, etc. What I DO know is that the specifications of the woofer/driver are match with the volume of the enclosure, where it is ported or sealed, the mass of the air that would be in the port, etc. Simply blocking a port might not have the desired effect. BTW - what is the desired effect?

 

[Robert D]

https://www.svsound.com/products/pb16-ultra

This sub has listed a ported and sealed mode stat. You can see how the numbers change. I'm pretty sure you just insert a plug into one of the holes.

Yes, listed as "foam tuning plugs".

 

[Tosh]

Vantage is special among all ML's in having transmission line bass. Fold up a towel and block it off for a listen!

 

[Pars]

The functional design of a bass enclosure is typically built to support a very specific "tune". Some others with more brain cells than I can probably provide details in terms of octaves, dBs, etc. What I DO know is that the specifications of the woofer/driver are match with the volume of the enclosure, where it is ported or sealed, the mass of the air that would be in the port, etc. Simply blocking a port might not have the desired effect. BTW - what is the desired effect?

If there is kind of too much bass, the idea is to port the plug and reduce it and get tighter bass (if nesessary)

 

[Pars]

Vantage is special among all ML's in having transmission line bass. Fold up a towel and block it off for a listen!

Wow! Tranmission line... I didnt know this. Doesnt it slow down the bass response? Panels are already fast for actual moving coil speakers, can Transmission line keep up with Panels regarding speed & Timing

 

[Pars]

https://www.svsound.com/products/pb16-ultra

This sub has listed a ported and sealed mode stat. You can see how the numbers change. I'm pretty sure you just insert a plug into one of the holes.

Yes, listed as "foam tuning plugs".

Well, more or less all ported cabins can be plugged but does it harm the speaker? anything from Martin Logan officialy recommended?

 

[Tosh]

Roger Sanders uses TL bass in all his ESL hybrids, but with active xo top and bottom (whereas Vantage only uses active xo in the bass).

 

[StimpyWan]

Since the Vantage speakers use transmission line loading, I wouldn't block the "port". But, many transmission line designs do use stuffing in the line for tuning and bass damping. As such, maybe order a bag of Acousta-Stuf polyfill from Parts Express. I would gradually add the polyfill (shove as much in as you can, a little at a time). Once you reach your desired bass response, stop and listen to a variety of musical genres, to see if the bass sounds balanced? Add or subtract as needed to further touch up the bass.

Good luck.

 

[ttocs]

Well, more or less all ported cabins can be plugged but does it harm the speaker? anything from Martin Logan officialy recommended?

When I had Vista speakers, I too was concerned with damaging the woofer if I plugged the port. But ML said it wouldn't damage anything, just would change the bass character. I stuffed a sock in each port and lived on very happily with the improved transition to the subwoofer.

The bass tightened up and had less low end extension. Also made the speakers easier to position in the room.

 

[Pars]

When I had Vista speakers, I too was concerned with damaging the woofer if I plugged the port. But ML said it wouldn't damage anything, just would change the bass character. I stuffed a sock in each port and lived on very happily with the improved transition to the subwoofer.

The bass tightened up and had less low end extension. Also made the speakers easier to position in the room.

this is exaclty the idea, if I get too much bass extension in my relatively small room.

 

[Heyfey]

Vantage is special among all ML's in having transmission line bass. Fold up a towel and block it off for a listen!

Vantage is special among all ML's in having transmission line bass. Fold up a towel and block it off for a listen!

Certainly looks like a TL. Here's what's on ML's website "Product Museum" for the Vantage:

8" (20.3cm) cast basket, high excursion, aluminum cone with extended throw drive assembly, non-resonance asymmetrical chamber format, bass reflex.

I guess "non-resonance asymmetrical chamber format, bass reflex" sounds more impressive than "transmission line?"

 

[R.I.P]

I used to have a KEF Q series bookshelf that came with a factory supplied foam to block the port. Based solely on this example if Vantage delivered with factory supplied material to block the port, then I imagine no harm to woofer may take place. And if allowed specifically in manual.

 

[jtucker]

It appears to be neither a conventional port or a transmission line. If it were a transmission line, back of the napkin calculation says it it tuned to approx 200 Hz. If I were going to stuff the port I would probably cut a piece of foam and maybe try a couple different densities. Also, the Vantage does have a bass level control. Maybe you can tune with that?