why add more wood blocks inside subwoofer?

Deal with the troll before it's too late. Every question in th.answers.yahoo.com has tons of blank answers (using space bar); it could have been posted by someone like Shadowfire to gain points for his troll accounts. In his questions and answers he always refers to Christian Lord God as “lord” / “god”; basically, when using proper grammar throughout his hateful blasphemous speech, he deliberately writes these two words from lower case letter. Jewish user Shadowfire (who spams this link “deathmetal.org/news/christ-sodomized” and has been on Yahoo Answers since the beginning and could possibly be the infamous homosexual flying antichrist from the tribe of Dan) from Portland [or so he claims because he could’ve been born in Russia in Valday (Russian: Валда́й) to a 12th generation Jewish prostitute who pretends to be a virgin)] has many trolls accounts on Yahoo Answers. These could be his accounts: Blackthorne1979, James Blackthorne, ✟ summer of night omega crow † ⚔, Saint James Tiberius Troll, Lord Shadowfire, Carter Berg, Madam Sin Bin, Fireball, Aravah, Miguel, ThatToiletguy, Tublet Huglet, Tut Uncommon: 3peat Offender, Cult Free, Reynaldo Weeks, Juli, Petri Lindroos, Uncle Fester, Lord Ninigi, Knightwulf, Nonplussed, Nightwulf, lyconpolis (lycon = wolf), Derick Fields, Toilet John, Hitler Was Right About The Jews, Master Debator, Magistra, Desiree, D-girl, Firecock, Yahoo User, Corvus Blackthorne, Patrick McCluskey,  Lord Aizen, Torchbug, Arni, r.wolfpaw, No Bozos, Fuzzface McGee, First Dragon, L.E. Gant, Fullofpoop, Shadowfire the Sarcastic, Pope of Atheist God, Jimson C. Raskin,  

A yellow face with simple open eyes showing clenched teeth,

El Nerdo Loco, megalomaniac, Corvia Blackthorne, Shadowfire Lives, Shadowfire Lives bytches, The Chick that wears Doc Martens, Homo, Wotan 8, Wotan (who keeps posting “satanisgod.org”), Heidi Ho, Clo Bird, Angels with Silver Wings, Orange I'lluminaughty, Christian Sinner, Gandalf the black, The Lord Hummungus, Mismatched Tube Socks, Pearl, Partysnax the Dragon, etc. and any other anonymous accounts. With one his accounts Fireball, he pretends to be a Methodist old lady who posts short-hand slang TIRH (this is religion here). He reports all answers and questions that he doesn't like just so that his questions stay on top in the Religion and Spirituality section. He trolls in other categories too. It gives Christians a bad name (just because of this troll's sock puppet account). His Toilet John account keeps posting questions where Jesus was sodomized by Roman soldiers. Remember the prophecy where it says that the antichrist will have personal hatred towards the real Jesus Christ. That’s why Shadowfire keeps posting thousands of similar questions along the line: “Did Romans sodomize Jesus?” or “Was Jesus anally violated during the crucifixion?” or "How many liters of cûm did Jesus swallow before being hanged on the cross to die?" or "Did Jesus take a big dick up the butt beforr dying?" or "Did Roman buttfck Jesus before crucifying him?" or “Did Romans buttrape Jesus?”. He asks multiple idiotic mundane questions like “Is Hinduism true?”, “What makes a girl harden?” [like he enjoyed killing little girls], etc. and answers them with his sock puppet accounts just to gain points. Some questions you can see that he answered with like five or seven accounts (especially the ones about himself that he reports right away). With his Reynaldo Weeks account he boasts that he was the reason why their accounts were suspended. With his Magistra account he threatens people with clowns and CIA assassins. Shadowfire mocks Christians with his sock puppet account Fireball in the Religion and Spirituality section by answering very destructively and adding "TIRH here" or reported (anonymously) or “fck you nigers”. He gives Christians a bad name because he promotes sins like sodomy, fornication, ecumenism, astrology (horoscopes), etc. He should be executed and burned at the stake for blasphemy. He spreads rapture heresy, reincarnation heresy, ecumenism heresy, etc. and many more subtle heresies. Antichrist will ride on a donkey into the 3rd Temple. Stop him before it’s too late. Antichrist is gay flying wizard who was born from a prostitute and who will ride on a donkey into the 3rd Temple. Antichrist's mother is a 12th generation prostitute (according to saint Lavrentiy of Chernigov). According to researcher Grigoriy Klimov, prostitutes = lesbians = witches; so, antichrist's mother is a witch, a lesbian, and a prostitute. Hide your kids, hide your wife ‘cuz de evil antichrist is flying thru town; take your glocks out and shoot dat son of a bytch down! Again, he’s an s-o-b ‘cuz his mother is a prostitute to Jews and Hindus. Funny thing is that she pretends to be a virgin. Don’t be deceived by this skumbag and his fake miracles trying to emulate Christ’s miracles! If wrongfully accused, forgive me; state under your account that you are not Corvus Blackthorne then. Shadowfire claims to be extraterrestrial raven when demons pretend to be extraterrestrials. I’m paranoid and think that all Yahoo accounts that talk about ravens are about him. Please, help me; I beg you. Using user Miguel, he’s teaching people how to summon demons. Dirty, very dirty! Shadowfire is a true dirtbag; do something to stop him now; he’s only one user and he’s doing the harm like it’s hundreds of users.

The length of the labyrinth puts the wave from the rear of the speaker in phase with the front of the speaker as well as being resonant at a lower frequency and makes the whole enclosure more efficient at those lower frequencies.

ask a question,,dude below gives you ten pages of religious spam,,,,,,

those baffles increase tight bass so the vibes do not cancel each other out,,,some speakers I bought in 71,,utah celesta 3wy coaxials,w paper and fabric cones,,they held up great for 30 years,the large cabinets had a cutout round panel that they guy used a large Mc Donalds plastic cup to vary the bass,a bit more of it inserted meant quite some more bass,,clean  bass too

Orthodoxy is the only true faith. Rapture = heresy; Fireball (aka Shadowfire aka Corvus Blackthorne aka Nightwulf aka Reynaldo Weeks) should be beheaded for spreading this heresy on Yahoo Answers (deceiving Christians into false hope). Dreams/thoughts are from 1)angels who always do good; 2)demons who never do good; or 3)you making shyt up in your head while you sleep trying to solve your problems; or from 4) your gov't using this supertechnology. Usually, dreams/thoughts are from demons. So, that explains a lot of people being in the wrong all the time. Rapture thing is from demons but you can't rule out the gov't using some super technology like Project Blue Beam to kind of introduce people to the evil flying antichrist who will ride on a donkey into the Third Temple. So, churches who closed for COVID (or had COVID measures like dipping spoon into some liquid like alcohol) are no longer Christ's but now are working for Satan promoting the new COVID religion. Last Patriarch is Patriarch Irenaios 1st. He blessed Catacomb movement. For liturgy what you need is antiminis (towel with remains of saints sewn into it); wax candles; one cup/one spoon; non-Kosher non-yeast non-barcoded non-qrcoded wine/bread. Kosher = sprinkled with blood. Yeast is grown on pig bacteria. QRcode = barcode = mark of the beast. Roman Catholics tried one cup and one spoon and got sick with Bubonic plague (no laughing matter). You must hide (within a small group of 10-15 people according to saints Gabriel Urgebadze and Seraphim of Sarov) in order to escape the unforgivable mark of the beast. No documents once you hid because documents are from Satan; burn all the documents that you can find. No electronics once you hid because antichrist's minions will track you using electronics that you got. Even old broken unplugged 1970 TV set will show the antichrist using Tesla's ether. In case you're in 'Murica and want to hide, then consider inland Alaska. Arctic Circle = Security Circle for WW3. If you manage to escape the unforgivable mark of the beast, then your direct ancestors will go to heaven (according to saint Vyacheslav Krasheninnikov). Thanks for reading this spiel. Forgive me.

The advantage is that the sub-woofer can play lower frequencies with a transmission line using the same driver in a similar size box with only a port.

Robert J gave a very good answer, 

to which I can add a little:   

Some cabinets have internal bracing to keep the panels from resonating.  

The larger the internal volume, the more likely it is that 

there will be some "extra" pieces inside for that purpose.   

That's a "transmission line" type enclosure, something like a derivative of a horn enclosure.

The long, labyrinth path causes a delay and changes the phasing of the sound from the rear of the sub driver.

Look up "Transmission line loudspeaker" on wikipedia for more information.