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Meaningful discussion outside of the potato gun realm. Projects, theories, current events. Non-productive discussion will be locked.
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Zeus
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Sat Jun 11, 2011 10:36 pm

Crna, I notice you're eagerly awaiting a release from Sony.
8/11/11 cant wait
I take it you're talking about that touch screen, mobile phone, WiFi media/gaming, PlayStation something?
/sarcasm, /hyperbole
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Crna Legija
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Sat Jun 11, 2011 11:31 pm

Zeus wrote:Crna, I notice you're eagerly awaiting a release from Sony.
8/11/11 cant wait
I take it you're talking about that touch screen, mobile phone, WiFi media/gaming, PlayStation something?

im typing about call of duty modern warfare 3and assassin's creed revelations there goes 200 bux :(
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Add me on ps3: wannafuk, 8/11/11 cant wait
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Technician1002
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Sun Jun 12, 2011 12:24 am

Crna Legija wrote:If my car head unit has 3 50w rca pre-outs(front+rear+subwoofer) and i have a 150wrms amp will it add the 50w to the 150?
The head unit does not put out power out the RCA jacks. Sorry that won't add. You can put speakers on the head unit speaker outputs and jack the RCA outputs into a power amp which will only put out it's rating.

Please note that there is several standards for measuring amp power. Peak power is based on the peak output voltage into the minimum load impedance. This is an advertising gimmick to give wimpy amps a high wattage number. True power is measured in RMS average into a nominal impedance. Often a 25 watt RMS per channel amp will knock the socks off a 250 watt peak power amp. Read the specs.

One puts out almost 50 volts peak to peak. The other puts out less than 24 volts peak to peak. I used to measure amps with a scope and dummy load. Don't buy the cheap junk based on the watts printed on the box.

More info..
http://www.outrageousaudio.com/page_fil ... attage.pdf

The old school way of measuring wattage was based on the maximum undistorted (not clipped) sine wave the amplifier could drive into a stated resistance load. Often the maximum distortion is given such as 0.01% THD. For example my band amp is rated for 500 watts RMS per channel (not total, thats 500 by two) into a 4 ohm load with both channels driven. Most car stereo is not measured by this standard. Cheap amps measure power by 100% distorted clipped peak power total into a artificially low impedance.

For example that amp will drive the load at about 45 volts AC RMS at a little over 11 Amps per channel. That is not clipped at 127 volts peak to peak into a speaker. That is not in the same class as a 500 watt amp that is lucky to hit a 40 volt peak without clipping.

Info on electric power is here with an online calculator.
http://www.sengpielaudio.com/calculator-ohm.htm

I have only tested one car amp that got my dummy load resistors too hot to touch. That amp had a 60 amp fuse.

Here is some specs from a real amp. It shows what power it will put out into a given load with what maximum distortion. Cheap amps won't provide these specs.

Output Power (typical all channels driven):
4 Ω, 1 kHz, 1% THD, 324 W
4 Ω, 1 kHz, 0.5% THD, 275 W
8 Ω, 1 kHz, 1% THD, 235 W
8 Ω, 1 kHz, <.019% THD, 175 W
8 Ω bridged, 1 kHz, 1% THD, 650 W
8 Ω bridged, 1 kHz, < .08% THD, 550W
Frequency Response (-3 dB): <10 Hz to 85 kHz ±3 dB
Frequency Response (1 watt): 20 Hz to 20 kHz, -.4/-.25
Crosstalk (adj. channels): -74 dB, 1 kHz @ rated output
Distortion (THD+N, 20 Hz to 20 kHz) (80 kHz LPF):
at rated power: < .06%
at 1 watt: <05> 100
Dynamic Range: 100 dB below rated output
Last edited by Technician1002 on Sun Jun 12, 2011 1:13 am, edited 1 time in total.
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Crna Legija
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Sun Jun 12, 2011 1:09 am

sweet thanks for that, i asked a car audio forum all they said was nope ahahha

its pritty week sytem 150w amp 300w kicker sub but i wanted sq not doof doof so its all right for my needs, if i get bord i can allways get a bigger amp.
'' To alcohol... The cause of, and solution to, all of life's problems.”
--Homer Simpson

Add me on ps3: wannafuk, 8/11/11 cant wait
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jackssmirkingrevenge
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Sun Jun 12, 2011 3:10 am

MrCrowley wrote:The cops might know it as "Crown vs. MrCrowley: unlawful tranquillizing of a female at a liquor establishment; evidence item: BA-36" :shock:
That implies there is a situation where one could do so within the law, good job if you can get it :)
hectmarr wrote:You have to make many weapons, because this field is long and short life
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mark.f
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Thu Jun 16, 2011 5:07 pm

Progress: $240 / $1300 towards PC build... it's gonna be a long summer. :roll: I should have it built in time to distract me from schoolwork this fall. :D
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Crna Legija
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Sat Jun 18, 2011 11:47 am

[youtube][/youtube]
'' To alcohol... The cause of, and solution to, all of life's problems.”
--Homer Simpson

Add me on ps3: wannafuk, 8/11/11 cant wait
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mark.f
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Sun Jun 19, 2011 1:12 am

[youtube][/youtube]
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Crna Legija
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Sun Jun 19, 2011 1:36 am

lol thats probobly what i sounded like last night :lol:
'' To alcohol... The cause of, and solution to, all of life's problems.”
--Homer Simpson

Add me on ps3: wannafuk, 8/11/11 cant wait
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LeMaudit
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Sun Jun 19, 2011 7:27 am

:shock:
I had no idea a macaron could do that!

The green ones maybe...
Image
...with some special herbs ans mushrooms :D
I HAZ A BANG!
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Labtecpower
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Sun Jun 19, 2011 9:07 am

what do you guys think of this scope?

I think about getting a few for my guns, and a future project.
a few pics;

Image
Image

Looks like a lot of scope for the buck. I am looking for accuracy up to 20 meters. (hitting a 10x15 cm can)
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jackssmirkingrevenge
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Sun Jun 19, 2011 9:26 am

The price is about right. Good enough for sub 30 metre spudgun purposes but not much else, the crosshairs have no markings to allow you to adjust for range and the sight picture is tiny.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Labtecpower
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Sun Jun 19, 2011 9:30 am

Spudguns are not very usable beyond 30 meters I think :D
seems perfect for my purposes...

Do you think it would be able to take the recoil of a 5000 joule hybrid ? I know, how long is a piece of string?
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jackssmirkingrevenge
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Sun Jun 19, 2011 9:56 am

Probably, because a hybrid recoils in one direction.

What usually breaks these cheapo scopes is the "whiplash" recoil of large springer air rifles.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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inonickname
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Sun Jun 19, 2011 9:59 am

To be honest, you don't need a scope to shoot at 20m at all...Especially not for can sized targets.
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