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Vanillagorilla
Intermediate Member
Username: Vanillagorilla

Post Number: 266
Registered: 4-2005


Posted on Tuesday, October 11, 2005 - 3:13 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Not that I'm ANYWHERE near this yet but I see a lot of amps..usually competition versions like FatBoy or Davemade rated at 15 to 18volts. How do you get say 16-18volts into the amp from a mobile install when the battery is giving 14.5v tops?
Just a question for future reference .:-)
I can see I'm BOUND to slap my forhead when I see the obvious answers.

Hank '905
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Patzerozero
Senior Member
Username: Patzerozero

Post Number: 1652
Registered: 7-2004


Posted on Tuesday, October 11, 2005 - 8:08 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

a 'motor maul', which is basically a step-up transformer, that brings up voltage, along with additional batteries & a total cost around $1000 is actually the easiest way to do it. you use your 'stock' alternator, though a high output aftermarket is suggested, & your vehicle otherwise runs as normal, electricals, charging system, etc. you can get around 18-20 volts & 350+ amps out of that system.

the bigboys go multiple leece-nevilles with external voltage regulators set to 18-20-22 volts, charging batteries is done by paralleling and/or adding 6 volt and/or using 24 volt batteries-read EXPENSIVE. that's why these guys use older suburbans/vans/big chevies-the vast amounts of room under the hood for adding multiples while keeping the stock system to run the vehicles.

to keep your chero as well as my mopar 'useable' the limit is probably 2 x 8 on a wrangler-type aftermarket alternator & dual batteries. that alt for my truck is over $900 from them, & the wiring upgrades probably add another $100-200, then either 2 or 3 optima batteries, also www.odysseybatteries.com just released a 2250 CCA 12 volt battery, though i'm not sure about the specifics just yet, at least another $600 for batteries, then the 8 pill around $700 depending on what you go with & $175 for the right 2 pill for it. so, to do 700 watt key/1600 watt swing the RIGHT way, you're up around $2600, assuming you have the radio & antenna...AND THAT IS EASIER & CHEAPER THEN 'VOLTING'...both you & the mrs need another job
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Vanillagorilla
Intermediate Member
Username: Vanillagorilla

Post Number: 267
Registered: 4-2005


Posted on Tuesday, October 11, 2005 - 9:31 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

uh huh....I Seeeeeeeeee. NO!

I was thinking on a slightly SMALLER scale :-)
Like a Stereo cap or reworking the alternator itself to run a smaller comp amp like say the X600. Was just thinking about the time the battery pos. lead fell (ok...ROTTED) off my old Bronco while I was driving it. The voltage meter was showing me 16+v without the battery inline.
Just started the wheels A turnin'.
Wonder if'n there's a way to split the alternator current feed? Hmmmmmm...lemme get to work on this one.
Pat, keep an eye to the east...see smoke dial 911.

'905
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Patzerozero
Senior Member
Username: Patzerozero

Post Number: 1656
Registered: 7-2004


Posted on Wednesday, October 12, 2005 - 4:02 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

had a 'built' alt in my blazer burn up the regulator. DXing away on LIE in queens & saw wattmeter go up BIG TIME!!! voltmeter was pegged & fried-battery scent filled the truck! took belt off & drove to patchogue-no traffic so motor temp stayed good-removed alt in parking lot & an hour later i was cruisin' again!
unfortunately, HE is no longer in business
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Wildrat
Intermediate Member
Username: Wildrat

Post Number: 140
Registered: 12-2003
Posted on Thursday, October 13, 2005 - 9:27 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Tell ya what, I just got my S9 and TS DX500 going and I go out to the Jeep the other evening to see if anyone was talking. My alt. on my 05 Jeep Rubicon Wrangler Unlimited is the stock one. I made contact with the fella, so then I go ahead and turn the amp on and key up, and I thought the Jeep was going to die. I pressed the gas a little and kept her going. I can use lo power without much problem, I hope I can find a bigger alt. that won't cost me a fortune.

Wildrat
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Chad
Intermediate Member
Username: Chad

Post Number: 489
Registered: 11-2004


Posted on Thursday, October 13, 2005 - 1:31 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

The question is weather the alternator is loading the engine that much or is the RF messing with ECM commands?
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Wildrat
Intermediate Member
Username: Wildrat

Post Number: 147
Registered: 12-2003
Posted on Thursday, October 13, 2005 - 2:39 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

No, it's not rf messing with the electronics, it's the alternator being loaded up and dragging the engine rpm down. Maybe that 117 amp dodge alt. will bolt up to the beast.

Wildrat

Sounds like an excuse to go to the junk yard. I'll have to take a few pics with the digital for ref. when I go. Anyone want to go to the junkyard, cost ya a dollar to get in.
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Tech808
Moderator
Username: Tech808

Post Number: 7601
Registered: 8-2002


Posted on Thursday, October 13, 2005 - 3:02 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Wildrat,

Just something to think about here.

We run Strobe Lights and revolving lights and Radios and Plows on our trucks and we bought UNDERSIZED ALT Pully's and a New Alt Belts for the trucks and it solved all our problems.

The smaller the pully the faster is spins and the more juice it throws back into the battery.

Nothing drains / ZAPS a battery quicker than Running Headlights, Radios & amps, Strobes & Revolving lights and PLUS the AM/FM/CD Players all at the same time and raising and lowering the plow and windows all night long.

Find an Alternator Shop near you and it will be a LOT CHEAPER than buying a New or Used/Rebuilt Alternator.

Hope this helps or at least gives you something else to think about.

Lon
Tech808
CEF808
N9OSN
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Chad
Intermediate Member
Username: Chad

Post Number: 491
Registered: 11-2004


Posted on Thursday, October 13, 2005 - 3:53 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Lon is right, an undersized pulley is the answer so that the alt is making more power at a lower engine RPM. A bigger alternator will not cause the engine less drag... power is power, energy cannot be created or destroyed. A bigger alternator is not going to magically make more power without pulling it from the engine. If anything it willow MORE drag as the coils will not saturate under heavy load. Get it spinning faster and I think you will be OK, although a larger alt is not a bad idea, I don't think it will solve the engine drag problem.

Think about this... I, and I know some others here use batteries and mobile gear at home. I charge via solar or pulse charging. No alternators, no high current supplies with the exception of batteries. But BIG wire being used because I want all that current available, it did not start out as a radio power supply but a very high current source for repairing audio amplifiers of competition caliber. They pull hard too!

Chad
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Hollowpoint445
Advanced Member
Username: Hollowpoint445

Post Number: 814
Registered: 6-2004
Posted on Thursday, October 13, 2005 - 6:47 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Don't larger output alternators generally need higher RPMs to reach their output level?

I've never run one but I remember a friend had one for his car stereo and his lights would dim more at idle with the large alternator than it did with his normal one.

He also had to get it rebuilt once a year but I don't remember why. I think it was the bearings.
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Wildrat
Intermediate Member
Username: Wildrat

Post Number: 149
Registered: 12-2003
Posted on Thursday, October 13, 2005 - 7:13 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Yep good idea, don't know why I didn't think about the smaller pulley. Thats what I do on my 72 Chevelle, and 46 ford to keep it charging good. Yes hollowpoint you do need to spin the higher output alts faster to get that rated output. I have a 200 amp for a chevy and it had to be spinning to get that output. I will look for another pulley and try that route first. I di want to goto the junkyard though. Haven'y been inover a year because of doctors practicing their trade on me.

Wildrat
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Wildrat
Intermediate Member
Username: Wildrat

Post Number: 150
Registered: 12-2003
Posted on Thursday, October 13, 2005 - 7:16 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

usually the regulator likes to go out on them because of the need for speed. It is better on those bigger alts to get one that you need to excite, rather than a one wire self exciter.I did have one that the bearings went out, but that was mainly because of water.

Wildrat
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Vanillagorilla
Intermediate Member
Username: Vanillagorilla

Post Number: 272
Registered: 4-2005


Posted on Thursday, October 13, 2005 - 9:15 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

All good stuff but perhaps we're not reading me right. I have no problem (yet:-)) with my current setup. TNT400 runs cool and never trips the 30a breaker. What I originaly wanted to know was how to feed a competition amp 16 to 18 VOLTS from the alternator. Underdrive and overdrive pullys have there place and yes...some of us can use them to our advantage..Lons rigs are a PERFECT example.
When an amp is rated at a certain output @ 16v I'd like to be able to supply it if I can. I don't see myself dropping in a maul or getting nutso with a second alt for something under 1k.
Perhaps I'm thinking too hard..been known to happen.

Hank '905
CEF 559
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Chad
Intermediate Member
Username: Chad

Post Number: 494
Registered: 11-2004


Posted on Thursday, October 13, 2005 - 10:37 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

They made a unit for car audio use to bring up the voltage for competition. I have no idea how it will react to RF. More importantly it is placed close to the amplifier and will REGULATE the voltage. It's a simple PWM DC-DC converter.

If I remember right it was made by Richard Clark and David Navone during the Autosound 2000 days they have since parted ways but I'll bet there's still something out there to do it. The way-cool thing is that it maintained ground integrity unlike other PWM designs, you won't be "volting" the whole car, just the amp, and ground is still ground!

I'll look around a little in the near future.

Chad
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Patzerozero
Senior Member
Username: Patzerozero

Post Number: 1668
Registered: 7-2004


Posted on Friday, October 14, 2005 - 4:34 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

905-"MOTORMAUL" or "LEECE-NEVILLE" which can be externally regulated to as much as 20+ volts. not a viable alternative to our small engine compartments. the motormaul allows you to be able to charge 12 volt batteries, the leece-neville needs MORE mods yet once you're delivering nearly double the battery's voltage.

smaller pulley makes the alternator recharge to its max output at LOWER ENGINE RPM only, if it's capable of 20 amps at idle & 65 amps at 2500 rpms, THAT IS ALL YOU WILL GET even by putting SMALLER pulley, all you can get is 65 amps, maybe revving engine to 1000 rpms as opposed to flooring it. of course, sitting on the beach revving high R's is NO good for engine, but it keeps the batteries charged. hollow, you are right, but my example above uses stock alt, 160-180-240 amp aftermarket alts WILL deliver much higher output at idle, in some cases 80 amps or even more, to reach FULL output, yes, revs need to be 2500 or MORE!

the dx 500 could be pulling 50 amps or even more, so unless you're cruisin' at 65mph, with ANY accessories on, you'll be forcing it to work too much. dual batteries helps keep volts up longer, but alt is still working hard. you really need to get alt around 100 amps for dx500. (my 117 amp alt & davemade is fine on AM, but in SSB, especially with HIGH input from S9, will swing well over 1kw & truck WILL buck & sputter & almost die-that is due to excessive demand drawing voltage away from the vehicles electronics).

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Bigbob
Senior Member
Username: Bigbob

Post Number: 2237
Registered: 12-2001
Posted on Saturday, October 15, 2005 - 8:05 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hey,one more thing guys,if your alternator belt sqeals and it is tight,don't spray with silicone lube you will defeat your purpose,don't put belt dressing on it it will shred,get dual pulleys or serpentine,more square inches=more watts.Bigbob

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