General Miata Chat A place to talk about anything Miata

Help me find a 12v source for my amp

Thread Tools
 
Search this Thread
 
Old 01-16-2012, 10:23 PM
  #21  
Cpt. Slow
Thread Starter
iTrader: (25)
 
curly's Avatar
 
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 14,206
Total Cats: 1,139
Default

Ok, so just tried hooking it up to 1R, and it worked great, car on or off. I really have no idea what power gremlins were working before, but it sounds great now, distorting only at the loudest of volumes. It easily drowned out my 1500rpm (cold engine) idle before distorting.

Here's my ghetto test, complete with twisted on extension to reach the MS harness:
Attached Thumbnails Help me find a 12v source for my amp-bbc7bd22.jpg  
curly is offline  
Old 01-17-2012, 09:51 AM
  #22  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,501
Total Cats: 4,080
Default

why you gotta ruin my harness?
Braineack is offline  
Old 01-17-2012, 11:43 AM
  #23  
Cpt. Slow
Thread Starter
iTrader: (25)
 
curly's Avatar
 
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 14,206
Total Cats: 1,139
Default

I was thinking about using a vampire tap. Maybe even two.

It's funny how pretty the left side of that plug is (Scott's work) vs. how ugly the right side is, with crimp connections and vampire taps. A lot of that is left over from my bandaid days. Most of the vampire taps aren't even in use, just afraid to take them off.
curly is offline  
Old 01-17-2012, 11:51 AM
  #24  
Senior Member
iTrader: (1)
 
jbrown7815's Avatar
 
Join Date: Apr 2010
Location: Portales, NM
Posts: 831
Total Cats: 2
Default

Glad you got it to work! Now you should write a guide on how to install it so I can do mine, lol

What is this 1R you speak of?
jbrown7815 is offline  
Old 01-17-2012, 12:47 PM
  #25  
Senior Member
 
WestfieldMX5's Avatar
 
Join Date: Nov 2007
Location: Belgium
Posts: 999
Total Cats: 73
Default

I'm surprised nobody notices that it's a 5A amp (60W), not a 0.5A amp.
IOW, run a wire to the battery and install a fuse within a couple of inches of the battery terminal.
The fact that it works with the 0.8A transformer is because you're not using all the power it can deliver. Double the sound level needs twice the power. Hence, you can achieve a very high sound level although you only have 0.8A
WestfieldMX5 is offline  
Old 01-17-2012, 12:48 PM
  #26  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,501
Total Cats: 4,080
Default

It's not a switch power source, the amp would never turn off and it would drain eventually....
Braineack is offline  
Old 01-17-2012, 01:01 PM
  #27  
Boost Pope
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Chicago. (The less-murder part.)
Posts: 33,049
Total Cats: 6,608
Default

Originally Posted by WestfieldMX5
I'm surprised nobody notices that it's a 5A amp (60W), not a 0.5A amp.
I was just going off of what was written on the body of the amplifier: "12V.5A"

In north America, we use the decimal instead of the comma to separate tenths of numbers from whole numbers. So whereas in most European nations, half an amp would be ,5A in the US and Canada .5A is half an amp.

Admittedly, 5 amps would make a lot more sense. 500ma is, well, not a lot of current.

Curly, is this thing fused? If so, what's the fuse rating?

(Wouldn't it be funny if this thing actually does draw 5 amps, and being wired into the ECU's supply, it causes a processor reset every time there's a loud musical transient while he's driving down the road?)

Originally Posted by Braineack
It's not a switch power source, the amp would never turn off and it would drain eventually....
Behold the magic and wonder of the $5 SPST automotive relay.
Joe Perez is offline  
Old 01-17-2012, 01:04 PM
  #28  
Boost Czar
iTrader: (62)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,501
Total Cats: 4,080
Default

just sayin'
Braineack is offline  
Old 01-17-2012, 09:05 PM
  #29  
Cpt. Slow
Thread Starter
iTrader: (25)
 
curly's Avatar
 
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 14,206
Total Cats: 1,139
Default

You mean 1R is not a switched power source? Because it turns off when I turn the MS off...

Maybe it's not 1R. Does it look like that's what I'm hooked up to? I read the MS harness diagram quickly and thought I was right in saying 1R...

No one's commented on whether or not this is a good (smart) source... I'm hesitant to run a $10 China amp to anything related to my MS.

Joe, it is not fused. It would be though. That's my next question, Ben mentioned running a fuse, and I have a inline fuse holder, but what size fuse?
curly is offline  
Old 01-17-2012, 10:30 PM
  #30  
Junior Member
iTrader: (1)
 
mx594m's Avatar
 
Join Date: Dec 2010
Location: Knoxville, TN
Posts: 279
Total Cats: 3
Default

Originally Posted by Braineack
It's not a switch power source, the amp would never turn off and it would drain eventually....
so add a relay energized by the switched 12v

beaten by Joe, thought there was a delete option
mx594m is offline  
Old 01-17-2012, 10:43 PM
  #31  
Boost Pope
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Chicago. (The less-murder part.)
Posts: 33,049
Total Cats: 6,608
Default

Originally Posted by curly
You mean 1R is not a switched power source? Because it turns off when I turn the MS off...
Yes, 1R is switched. Brainey was talking about wiring the amp directly to the battery (which I still maintain is the best possible solution, obviously with a relay inline.)


No one's commented on whether or not this is a good (smart) source... I'm hesitant to run a $10 China amp to anything related to my MS.
I commented on it, and rather sardonically I thought. Specifically, I said "Wouldn't it be funny if this thing actually does draw 5 amps, and being wired into the ECU's supply, it causes a processor reset every time there's a loud musical transient while he's driving down the road?"


That's my next question, Ben mentioned running a fuse, and I have a inline fuse holder, but what size fuse?
The more I think about it, the more I'm agreeing with Frank. There's no possible way this thing can operate on 500ma. That's less current than Hustler's mom's cheapest motorized ***** draws.

I'm thinking that the Belgain guy is right, and some lazy dipѕhit in a Chinese sweatshop simply made a typo when she was creating the silkscreen, inserting a decimal where there shouldn't have been one.

As such, you should probably fuse the device at 5A. Fuses don't blow instantaneously at their rated current, and unless you're playing a sine wave at maximum volume (or a modern hip-hop album, which are essentially the same thing) the amp is not going to draw rated current continuously. If the fuse does blow, then replace it with a 7.5 amp unit.
Joe Perez is offline  
Old 01-17-2012, 10:57 PM
  #32  
Cpt. Slow
Thread Starter
iTrader: (25)
 
curly's Avatar
 
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 14,206
Total Cats: 1,139
Default

Gotcha, 5a it is.

I read your reply, and half heatedly laughed out loud, didn't know it was a serious concern. I guess I'll find out.

Can't open the doors in my puny garage though, so it'll have to wait for the weather to chill out, perhaps tomorrow. It's currently rainsnowing.
curly is offline  
Old 01-21-2012, 12:38 AM
  #33  
Cpt. Slow
Thread Starter
iTrader: (25)
 
curly's Avatar
 
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 14,206
Total Cats: 1,139
Default

So for anyone interested in a cheap amp, this one works fine.

I ended up tapping into that 12v source feeding the MS, soldered in a fuse, and it's working great. It's still distorting at the loudest of louds, but it's still easily audible at freeway speeds in my stripped car with a solid motor mount, so there's really no point in it getting louder. Can't ask for more for $10 really.
curly is offline  
Old 01-24-2012, 02:41 PM
  #34  
Senior Member
iTrader: (2)
 
Tekel's Avatar
 
Join Date: May 2010
Location: Beckley, WV
Posts: 851
Total Cats: 37
Default

I wired up an amp very similar to this one (except it cost me $40 not $12, I think I got ripped). I wired to the 12v source that was originally meant for the radio. I also wired an on/off toggle in line as well so I can turn the amp off when not in use.
Tekel is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Full_Tilt_Boogie
Build Threads
84
04-12-2021 04:21 PM
Pist0n
Supercharger Discussion
6
08-02-2019 05:27 PM
shooterschmidty
Engine Performance
8
09-30-2015 10:28 PM



Quick Reply: Help me find a 12v source for my amp



All times are GMT -4. The time now is 03:48 AM.