Front port v Rear port

[8009514]

Having purchased a Denon DM37 late last year, decided to put some better speakers with it to replace the old Sony things I had. Shortlisted the MA BR1s and the MS 902i. Unfortunately unable to compare both in the same conditions. Severnoaks Bristol don't do the MS and Richer don't do the MA. After much walking between the two (luckily they're pretty close to each other) I plumped for the BR1s. Definate improvement on what I had previously so am really happy with the system.

However, it's got me thinking. People who buy micro all in ones are probably doing so because of space restrictions, so will more than likely buy bookshelf type speakers for the same reason. This also means that the speakers are more than likely to be positioned on or very close to a wall. The BR1 speaker is rear ported, so is probably more likely to create bass boom than a front ported unit in the same position. MA do supply foam bungs to block the port to prevent this occurring.

2 Questions

1. The port is there for a reason, so what does putting a bung in it do to the performance of the speaker?

2. Would a front ported speaker be a better option when positioning on or close to a wall?

 

[d_a_n1979]

Q1 - The port is there to allow air to travel in/out of the speaker as the woofer will be creating a push/pull effect.

Pushing air out of the unit will also allow the bass sound waves to travel allowing for a deeper bass note.

Q2 - Speakers that are forward firing are better for placing closer/against a wall, if necessary, but its not always recommended! It will still create bass boom but not as much as a rear firing speaker.

Please note; this is just my opinions/ideas on the bass ports. Im not a speaker techy etc... Just a bit of common sense and knowledge!

 

[Anonymous]

It doesn't matter where the port is because low frequencies radiate through 360 degrees.

The enclosure behind the drive unit and the port from it produce a resonance as you get from an organ pipe or an expansion chamber on a two stroke racing motorbike. Because your ears are not very sensitive at lows frequencies and small speakers cannot reproduce bass, the port gives a reasonable illusion of the real thing.

Boom is a function of the Amplifier's power and damping factor, drive unit performance and the impact on damping factor caused by resistance in the crossover. Low powered amps boom because they might not be able to produce enough power and others do so because they have a high output impedance. Lots of power and low output impedance are best. If you're having trouble, block the port because it will stop the resonance and may produce a better balance

 

[drummerman]

There's a possible problem with front ported speakers which utilize badly designed cabinets or port design and/or lack of sufficient internal damping material, of mid-range sounds leaking through the port. It usually manifests itself as a hollow quality to sound and/or a 'honk' at certain frequencies. Something I've noticed on Rega's floorstanding designs, otherwise is a nice speaker. This is less a problem with rear ported speakers.

 

[Anonymous]

I think you need to find a happy medium somewhere.

Small sealed-box loudspeakers like SA1 can sound awful and strained, whereas other small loudspeakers that are heavily reliant on the bass port can boom.

A bookshelf speaker with a modest port is the best compromise. Listen to a few.

Those Monitor Audios are fine, except for the nasty metal tweeter.

 

[fatboyslimfast]

Eddie Pound:except for the nasty metal tweeter.

...in your opinion Eddie.

 

[drummerman]

fatboyslimfast:Eddie Pound:except for the nasty metal tweeter.

...in your opinion Eddie.

... and mine.

 

[Anonymous]

Me too!

I persuaded my step dad to listen to the system you are about to buy (denon micro and br1). He loves his music and used to listen using a basic surround sound system. After listening, he flexed his card and left the shop £320 lighter but with a grin from ear to ear.

I think they sound pretty enjoyable but definately a bit toppy. He LOVES them.

I hope you enjoy your purchase!ÿ

ÿ

 

[fatboyslimfast]

Ah, but see I have a ton of soft furnishings and slightly damaged ears, so they sound just right to me!

Which, although seeming rather OT, is an important point. What works for one person doesn't for the other...

 

[d_a_n1979]

fatboyslimfast:What works for one person doesn't for the other...

Exactly!!!

Winds me up when they whole heartedly slate something THEY dont like; it can damage peoples opinions before they even demo the item!

Everyones hearing is different; i personally found the M/A tweeters spot on; more so when partnered with Arcam gear

 

[drummerman]

d_a_n1979:fatboyslimfast:What works for one person doesn't for the other...

Exactly!!!

Winds me up when they whole heartedly slate something THEY dont like; it can damage peoples opinions before they even demo the item!

Everyones hearing is different; i personally found the M/A tweeters spot on; more so when partnered with Arcam gear

Don't take it personal buddy and yes, they do work better with Arcam than some others. An A38 was infinitively preferable to Roksan's K2 with some RS6's.

Still did'nt work for me though