My experience of bunging the bass-port

Milco

Active Member
Yesterday I took delivery of a pair of speaker bungs for my Dali Opticon 2s, so I thought I would post my experiences with them.

In a nutshell, my reason for trying speaker bungs is that due to the fact that my listening room is in a fairly small extension the speakers are only around 8 inches from the rear wall and roughly the same distance from the side walls. Bass extension from my Arcam A-18 amplifier is very good, but I have always found the bottom end slightly woolly, and 'musicality' and articulation in the bass could be a little better. I thought on that basis that bungs were worth a try.

My test track was 'Mumps' by 1970s jazz-rockers Hatfield and the North: a track lifted by a wonderful, exuberant Fender Jazz bass guitar, played by Richard Sinclair, containing plenty of bottom-end grunt along with mid-range definition, detail and articulation.

As the track rolled I sat there instantly slack-jawed! The difference in sound using the bungs was astonishing! It was like all the body-hugging, room-filling bass energy had been sucked out of the track. It was as if my Opticon 2s had been neutered. All the oomph and the energy, all the stuffing, weight and heft was missing. Despite this spectacular reverse, I listened carefully to see if there was any corresponding increase in mid-range detail and articulation in the bass. There was absolutely none. If anything the lack of any underpinning bottom end diminished all the other sound information coming out of the bass guitar.

The bungs didn't last the full duration of the track (albeit it does last twenty minutes). My sense of relief when the bungs were out and the speakers rumbled and punched with their usual bass intensity was enormous.

So, I'm afraid it was all pain and no gain for me with the speaker bungs. Never before have factors like room placement and positioning been made so obvious to me than with my bungs experiment yesterday. It was like night and day. Needless to say, if you have to place your speakers directly up against a wall and actually need bungs you are probably losing a sizable chunk of your speakers' potential with your positioning compromise. I was utterly gobsmacked! Mine would probably benefit being a further 8-10 inches out into the room, but the bungs are now in the bin!
 

Steve356

Distinguished Member
Yesterday I took delivery of a pair of speaker bungs for my Dali Opticon 2s, so I thought I would post my experiences with them.

In a nutshell, my reason for trying speaker bungs is that due to the fact that my listening room is in a fairly small extension the speakers are only around 8 inches from the rear wall and roughly the same distance from the side walls. Bass extension from my Arcam A-18 amplifier is very good, but I have always found the bottom end slightly woolly, and 'musicality' and articulation in the bass could be a little better. I thought on that basis that bungs were worth a try.

My test track was 'Mumps' by 1970s jazz-rockers Hatfield and the North: a track lifted by a wonderful, exuberant Fender Jazz bass guitar, played by Richard Sinclair, containing plenty of bottom-end grunt along with mid-range definition, detail and articulation.

As the track rolled I sat there instantly slack-jawed! The difference in sound using the bungs was astonishing! It was like all the body-hugging, room-filling bass energy had been sucked out of the track. It was as if my Opticon 2s had been neutered. All the oomph and the energy, all the stuffing, weight and heft was missing. Despite this spectacular reverse, I listened carefully to see if there was any corresponding increase in mid-range detail and articulation in the bass. There was absolutely none. If anything the lack of any underpinning bottom end diminished all the other sound information coming out of the bass guitar.

The bungs didn't last the full duration of the track (albeit it does last twenty minutes). My sense of relief when the bungs were out and the speakers rumbled and punched with their usual bass intensity was enormous.

So, I'm afraid it was all pain and no gain for me with the speaker bungs. Never before have factors like room placement and positioning been made so obvious to me than with my bungs experiment yesterday. It was like night and day. Needless to say, if you have to place your speakers directly up against a wall and actually need bungs you are probably losing a sizable chunk of your speakers' potential with your positioning compromise. I was utterly gobsmacked! Mine would probably benefit being a further 8-10 inches out into the room, but the bungs are now in the bin!

Same experience for me some years ago with a pair of Dynaudio Contour 1.8 Mk2 speakers. Putting bungs in them not only neutered the bass frequencies, but also negatively impacted the mid range. Sometimes bungs can bring some benefit, but not always.
 

Milco

Active Member
Bottom line is: you gotta feel the bass. It's part of the joy of having a hi-fi. It's part of the dopamine pleasure of the whole thing!
 

FootHealer

Active Member
Every time I try port bungs, I always feel the speakers are better without them. For me, I use front ported 6.5 inch bookshelf speakers upstairs in a smaller room. They are 10cm from the wall but sound fine. I have a small 5 inch pair on my PC, which are rear ported, but have very modest bass, so the 15cm proximity actually improves the bass. Downstairs, if I push a rear ported pair of floorstanders too close to the wall, the bass bloat is awful. I keep them about 1.5 feet out into the room. I tried port bungs. Made the speakers sound anaemic. I have another pair of front ported floorstanders. These can be taken pretty close to the wall without much issue.

I guess ports need to be a factor we consider when buying speakers to place in our homes. If you have little space, and the speakers need to be again a wall, picking a front ported speaker may be best. Or if the room is small, picking a small rear ported speaker can actually work in our favour.

This is my experience.
 
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Ugg10

Distinguished Member
I think the port bung use is quite speaker dependent and if the speakers were not supplied with them then they may not help (or worse as you have found). I know Kef supply some of their their speakers with them and they are usually a two part affair where you can remove the centre and partially bung the port so you can tune to some extent. This is why I usually suggest using rolled up socks or a towel which you can roll tightly or loosely to tune.
 

steve sph

Well-known Member
I'm not one for 'feeling' the bass personally - for me it's just one component, (albeit an important one), in establishing a coherent overall sound.
So for me a well-positioned and well-calibrated speaker doesn't really need need it's signature sound altering by sticking bits of foam in holes - in fact the very thought must irritate speaker designers beyond reason.
If you have the room for the speaker you want to operate as it was meant to then buy it - if you're restricted by space then buy a speaker that doesn't need it.
 

FootHealer

Active Member
If you have the room for the speaker you want to operate as it was meant to then buy it - if you're restricted by space then buy a speaker that doesn't need it.
Absolutely! But people (myself included) often buy speakers based on reviews, hype, brand loyalty, etc, and may have to make them fit their situation (e.g. using port bungs) rather than purchasing something to fit their living space and taste. With so much choice available, there is almost certainly something to satisfy all ears without the need to constrain them. If I were a speaker designer, the thought of someone stuffing socks or 2p worth of foam into the finely tuned ports of my creation would make me a bit disheartened. Like asking a singer to perform with their mouth full. Chosing the right speaker isnt always easy. Mistakes are plentiful. I should know... I've made many myself ;)
 

dogfonos

Well-known Member
I strongly agree that a speaker should fit the space available i.e. be a good size fit for the room. Ideally, the speaker's bass loading design should also suit its likely position within that space. However, not everyone chooses a suitable speaker for their listening room (been there, done that myself). Also, almost all speaker designs are compromised to some extent and there are trade offs (e.g. cabinet size is usually prioritized over bass performance), probably more so at the budget end of the market. Therefore, in some circumstances, modifying a speaker's port, by blocking or partial blocking, can beneficially alter the sound.

I once used too large a speaker in my room (Mission 770 in a 12 -15 sqm room - what was I thinking!). On one particular track (Rickie Lee-Jones, Chuck e's in love), the unadulterated speaker gave a strange double bass drum hit (the second hit coming a fraction after the first). When ports were blocked, the bass drum hit was clearly a single drum hit. I settled on a partial block which gave the best bass in that room.
 

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