Enclosure Question

[diplomata]

Hello east electronics

Check out what visaton did for its kit "La Belle", you can get ideas from there only that it is a closed project and not bass reflex.

best regards

Carlos

 

[GM]

Some people believe that when you use two bass drivers in the same cabinet, you should isolate the volume for each driver. In essence, you make two cabinets within the box.

You will need to make up your own mind on this, because not everyone believes it is important. In my opinion, if the bass alignment is a vented box, then each driver should have its own volume and its own vent. If it is sealed, the two drivers can share the box volume. I do not have a scientific basis for this opinion, it is just my engineering judgment.

It depends on the needs of the app.

For most HIFI/HT apps it doesn't matter, so I normally recommend a well braced common box/vent regardless of the number of drivers if they are measured, then designed based on the averaged specs.

For some of these 'insane' mobile audio, HT, prosound apps or even my favored pipe organ symphonies, they should be individually tuned alignments since as the motors can reach many hundreds of degrees in a heartbeat due to heat rise being exponential; the one that starts out drawing a little more current can quickly 'starve' the other, making it little more than a 'slave', then the amp sucker 'grenades' from trying to drain the amp dry and of course the slave pops in near unison as it tries to take up the slack.........all over but the smoke/fire before I could type it.

This used to be a common occurrence in prosound and sadly seen it in one of my early systems, but amps protect them pretty good nowadays, though still a good plan as an extra layer of protection.

As for cab room modes, unless it's so big the 1/4 and/or 1/2 WLs are down in the driver's gain BW like with an MLTL, not an issue, so only need minimal damping if a sufficiently rigid construction is used, though always a good plan to have good damping directly behind the driver.

GM

 

[GM]

How about taking advantage of having two woofers and tune them differently to smooth the response?

Or extend BW, an extreme example: http://community.fortunecity.ws/rivendell/xentar/1179/theory/dddllqd/dddllqd.html

GM

 

[GM]

No, I meant two reflex cabs tuned differently

Dr. Geddes has posted that his multiple sub woofer HT has all manner of alignments to best deal with in room response, so no need to limit to anywhere near same alignments, though can't recall whether he limits driver choice, but I doubt it.

GM

 

[scottjoplin]

Yes, I think he suggests variety in every way is useful.

 

[AllenB]

Two differently tuned boxes viewed from a single location will present an amalgam of the two, just like each being tuned in the middle (on the other hand each box will have different spatial duties in a room, but this no longer has anything to do with tuning relatively between each box). Many designers have pursued this tangent and some have sold the idea, I find it fascinating myself, but it hasn't persisted.

 

[scottjoplin]

A bit off topic but since the OP hasn't come back yet.......

The best thing I've done bass smoothness in room so far, has been a corner infinite baffle, other than a single peak at ~40Hz it's very smooth everywhere in the room