Linear Excursion

[nametaken 10+ year member]

the are you constantly calling thr w7 dub7? IMO your giving it a bad Audiobahn esque feature.
And i am 100% behind Jmac. I am not *******, it's because in the past he is literally never ever wrong.

Yea it does sound audiobahnesque i admit, but i was geting bored //content.invisioncic.com/y282845/emoticons/veryhappy.gif.fec4fed33b4a1279cf10bdd45a039dae.gif

Haha, havent seen hiw wrong either.

What does the guy mean........ it has 2 inch peak to peak then it can "shift gears" and go to 4 inch p2p........ wtfs that supposed to mean. W7 has a sub ****** for bigger rooms.

The gotham/fathom(i think too) can be set specifically for your room. So in a very small room it might not have to use all that 4" to get the bass needed. But when set in a big room and it needs that xtra output for a loud explosion, i guess its starts pumping out 3600rms to get that excursion.

Speaking of which, in order for you to have that muchpower youde need ALOT of current, more than a house could provide. SO maybe instead of using tons of amperage mayeb they use voltage instead. But this would mean that the impedance of the subs would have to be higher correct(i think the average outlet can only provide soemthing like 15 amps?). Im too hungry to do the math, i need to eat breakfast.

 

[JimJ 5,000+ posts]

I would assume that a true 3.8kW home audio amplifier will be 220V, as the current draw on a 120V single-phase circuit would be way, way too much. Even at 80% efficiency, that's still over 50 amps of current draw. Most residential 120V circuits max out at 25A...

 

[its_bacon12 10+ year member]

word....

dass alotta power //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

maybe its more suitable to theatres? where they have the power to supply

 

[80INCHES 5,000+ posts]

What does the guy mean........ it has 2 inch peak to peak then it can "shift gears" and go to 4 inch p2p........ wtfs that supposed to mean. W7 has a sub ****** for bigger rooms.

//content.invisioncic.com/y282845/emoticons/rotflol.gif.b453361716769b8110ddefc85ff03cd2.gif//content.invisioncic.com/y282845/emoticons/hilarious.gif.02a037aad04aa96f19982b298a3d70a8.gif

good point

80

 

[supa_c 5,000+ posts]

I would assume that a true 3.8kW home audio amplifier will be 220V, as the current draw on a 120V single-phase circuit would be way, way too much. Even at 80% efficiency, that's still over 50 amps of current draw. Most residential 120V circuits max out at 25A...

There is an old thread on what kind of electrical system you would need in your house to run this thing.

 

[audioholic 5,000+ posts]

The excursion specs the JL guys talked about in that video were always referred to as "peak to peak". This is NOT linear, this is physically how far a subwoofer is capable of moving. Are the great guys at JL lying? No. But they are not speaking about linear excursion either. Which is rather confusing/deceiving. Sorry nametaken, but you've utterly 100% wrong from the get-go. And furthermore, if JL is so proud of their sub, why do they refer only to P2P specifications? Its a BS advertising video for people who know nothing about subwoofers. That is the LAST place you should be drawing your 'facts' from. lol

 

[nametaken 10+ year member]

The excursion specs the JL guys talked about in that video were always referred to as "peak to peak". This is NOT linear, this is physically how far a subwoofer is capable of moving. Are the great guys at JL lying? No. But they are not speaking about linear excursion either. Which is rather confusing/deceiving. Sorry nametaken, but you've utterly 100% wrong from the get-go. And furthermore, if JL is so proud of their sub, why do they refer only to P2P specifications? Its a BS advertising video for people who know nothing about subwoofers. That is the LAST place you should be drawing your 'facts' from. lol

*Sigh*

Just to show the mass people how much the thing can move(and i acknowledge its marketing, never said it wasnt), them saying its moves 40mm one way would kinda be //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif for regular folks(again, its marketing i know). And i never said it was a fact, please show me where i said it. I even stated it was hear say(no specs about the sub), but i doubt theyde lie so thats why i gave them the benefit of the doubt. And like i said before, it probably doesnt move 50mm but maybe higher 40's, which is still an assload.

 

[nametaken 10+ year member]

You're right that the voltage will, most likely, be higher than a typical outlet (Most likely 220 volt as Jack said) because most houses wouldn't be able to supply the current without serious upgrades to their electrical systems.
Efficiency = Power Out/Power In

Current = Power/Voltage

At 60% efficiency (approximate efficiency of the 1000/1), you'd be looking at:

0.6 = 3800/Power In

Power In = 3800/0.6

Power In = 6333.333 watts

With a 110 volt outlet, this translates to 6333.333/110 = 57.576 amperes ...

With a 220 volt outlet, this translates to 6333.333/220 = 28.788 amperes ...

The voice coil's resistance, however, will only affect the voltage on the amplifier outputs, though //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

Ahh. So a sub isnt seing much current, just the amp?

 

[audioholic 5,000+ posts]

*Sigh*
Just to show the mass people how much the thing can move(and i acknowledge its marketing, never said it wasnt), them saying its moves 40mm one way would kinda be //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif for regular folks(again, its marketing i know). And i never said it was a fact, please show me where i said it. I even stated it was hear say(no specs about the sub), but i doubt theyde lie so thats why i gave them the benefit of the doubt. And like i said before, it probably doesnt move 50mm but maybe higher 40's, which is still an assload.

I dont know what the sigh was for, you seem to be acknowledging that everything I said was true.

 

[nametaken 10+ year member]

I dont know what the sigh was for, you seem to be acknowledging that everything I said was true.

I sighed because i have to explain something that i really dont have to, if you really took the time to read what i wrote i wouldnt have to break it down. And i didnt acknowledgs everything, just clearing up for you what i really did say/imply.

Ohm's Lawower = Voltage*Current

Power = Voltage*Voltage/Resistance

Power = Current*Current*Resistance

3800 watts into a 3 ohm load would be: 3800 = I^2*3, I = Sqrt(3800/3), I = 35.590 amperes. V = 106.771 volts

So the amp would pull 28.788 amperes of current from the outlet at 220 volts to output 35.59 amperes of current at 106.771 volts to the subwoofer ...

Of course, this won't be completely correct as the driver doesn't have a static resistance. Instead, it has impedance which fluctuates with frequency.

Ahh, its all coming back to me, physics class is kinda fuzzy, must be the summer break //content.invisioncic.com/y282845/emoticons/tongue.gif.6130eb82179565f6db8d26d6001dcd24.gif

 

[audioholic 5,000+ posts]

I sighed because i have to explain something that i really dont have to, if you really took the time to read what i wrote i wouldnt have to break it down. And i didnt acknowledgs everything, just clearing up for you what i really did say/imply.

Oh I took the time, you just talk in circles. Im just wondering, if you do acknowledge this is P2P and not linear displacement, why did you even bring it into a discussion about linear displacement in the first place? And furthermore, why are we still talking about it now?

 

[80INCHES 5,000+ posts]

i wish threads were more like this........very useful knowledge on this thread

80

 

[supa_c 5,000+ posts]

Nametaken, face it, you lose.

 

[azbass 5,000+ posts]

I bet that thing sounds nastyThe infamous " wooshy" sound from W7's would be quite loud

iv never heard wooshy sounds from a W7, ever. to be honest.

 

[JoseMCeee 10+ year member]

iv never heard wooshy sounds from a W7, ever. to be honest.

did Supa C say that? Lol still going at it eh... //content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif