does anyone know how i can play guitars off a car battery

[versuviusx]

hi i was wondering if anyone knew the best way to play a guitar amp off of a battery for recording sessions. i'm looking for the cleanest power i can get and i was thinking a battery would be the best way. any suggestions? i'd like to see what the difference would be in quality of sound. i was thinking maybe a UPS would work and i could run it off one unplugged after i charged it. but if anyone has any better solutions....i'm all ears.

[PeterSawatzky]

Why do you want to run your amp off a battery? If you're recording, what's your recording gear plugged into? Why not use whatever that is?

Anyway, if you really do want to run an amp off a car battery, you could use an inverter. These are available at most hardware stores, or Wal-Mart or whatever. Just make sure the power capacity of it matches your amp's consumption (not output! A 40 W tube amp can consume as much as 100 W.) and keep in mind that car batteries are designed for short bursts of very high current, not continuous use. Also, inverters put out rather dirty AC no matter how clean the DC input is. So if your amp has limited AC filtering (as found in a vintage and/or cheap amp), that dirtiness will translate into audible noise.

[markitzero]

The problem is you need an inverter to go from DC to AC. You can get a unit by the company Xantrex for $300 that supplies 15 amps/125volts for probably 2 hours on a guitar amp. The unit is primarily designed as a portable power supply for marine/camping use. CAUTION: these types of units put out a square wave as opposed to a sine wave (like a household outlet). Therefore, with some audio equipment, you will get a nasty 60 hz square wave buzz. Trust me, I've delt with this problem a lot lateley. My company just had a large job where we riggged up 6 golf carts with battery powered PA systems and slapped a wireless lavalier mic on a certain legendary pro golfer. We drove the carts around while he played all 18 holes of this exclusive golf course he designed, and the whole time he was addressing a crowd of 1000 that were following him around the course. We delt with this freaking square wave thing for days before the event, and eventually went with equipment that was less succeptable to the square wave thing than some others were. In the end, the buzz was still there, but it was fine because we were not in an environment where a low noise floor was necessary.

Anyway, yea, you need an inverter or a dedicated rechargeable unit. Beware of buzz.

[jv]

I wouldn't use an inverter for recording unless it was an expensive sine wave type inverter. The power that the "modified sine wave" (square wave) inverters put out is crap. At the best, you'll get a buzz, at the worst it could damage your equipment.

[???????]

This is impossible. Your power transformer in your amplifier is designed to step 120 volts AC up to 500 volts (or more!) for the plate voltages, and numerous other voltages. The filaments on your tubes are going to be powered off of AC. The transformer winding for those steps down from 120 VAC to 6.3 VAC.

A car battery is typically about 12 volts DC. No dice. Sorry.

You could wire your amp for DC filaments but that's an extensive modification.

[ToddP]

I think your premise is incorrect. For clean power, get a voltage regulator. ETA PCI series or Furman AR series or something (not a power distribution strip, but a conditioner/ regulator). At least I think that is what you are getting at...

[KennyLusk]

This is one of those Trick questions, isn't it?

[parlormusic]

Back in the day...
I used to use a 300W power inverter with a RV battery (so that it can be recharged numerous times). This ran my bass amp just fine. However, there is a better way...

You'd get much cleaner power from the battery side of a UPS. You can keep it plugged in to the wall outlet because the battery backup outlets on the UPS are decoupled from the direct feed from the AC supply. I'm not absolutely sure, but I think that power from the UPS battery will provide a more stable voltage as well - without the voltage drops & spikes you'd typically get from the wall outlet. That's why I have my critical studio gear plugged into the "backup" UPS outlets.

[oh_sweet_nuthin]

I'm sorry, I can't add to any of the technical information in this thread, however I can toss in an anecdote.

A couple years ago I wrote a story about a former-Mennonite singer-songwriter from Western Kentucky named John Christopher McKnight. He lived on his farm with his seven kids, and taught all of them to play different musical instruments. The farm didn?t have electricity, so he somehow wired up a small practice amp to a car battery so his little girl could play electric bass. I?m not sure how he did it, but it was pretty cool.

[Mark Alan Miller]

For that latter example, there are small CD-powered practice amps out there, and it's a simple feat to step the voltage down from car battery to whatever they require (if one even needs to step it down!) These amps are no JCM900's though...

[parlormusic]

For that latter example, there are small CD-powered practice amps out there, and it's a simple feat to step the voltage down from car battery to whatever they require (if one even needs to step it down!) These amps are no JCM900's though...

CD powered amp? Kewl! I knew some CDs had a ton of energy, but who would have thunk?!

[konabuzz]

Interesting thread......

I agree, having used inverters in an audio setting -- noise always seems to creep in, and that is truly maddening.

If tone is not particularily an issue (and I concede... when it is not?) a little Roland Micro Cube is actually not a bad noisemaker. And it runs off batteries...and it has a record out to boot. However, if you go that route, an amp-sim module (Pod, etc.) would be the better choice -- more parameters, etc.

The UPS is a clever idea I hadn't considered.....hmmmm.

Maybe a little off topic, but......

I happen to work for the local phone co. and am mobile all day. Occasionally I have a bit of down time, and have equipped my work van as a sort of lo-fi studio on wheels. I use a full sized 12v car battery mounted to the floor, which is kept trickle-charged via a solar cell on the dash. Works well. Several cigarette lighter multivoltage adapters furnish power to my Laptop, Zoom PS-04 4 tracker, Behringer battery-powered mixer, effects, drum machine, keyboard, powered speakers, etc. etc. Over the top? Reaching? Perhaps....but I have fun. Good as an elaborate sketchpad type thing.

[Mark Alan Miller]

For that latter example, there are small CD-powered practice amps out there, and it's a simple feat to step the voltage down from car battery to whatever they require (if one even needs to step it down!) These amps are no JCM900's though...

CD powered amp? Kewl! I knew some CDs had a ton of energy, but who would have thunk?!

Arf Arf! Good ol' typos that have their own meaning...

[philbo]

If you can find a small amp, with a schematic diagram that indicates the power supply puts out 12 to 15 volts DC, you can wire the battery in across the power supply and it will run it fine... It'll doubtless have to be solid state amp, since tubes won't directly run off a single 12V supply.

Real long shot:
Find a rig with dual-layer power.
(It's conceivable there's an amp out there with a dual-layer switching supply... but sort of doubtful. In that type of supply, the AC is first converted to a fairly high DC voltage, like 50 to 90 or more. This is used to charge a good-sized bank of capacitors, with extra filtering to remove any AC (residual) ripple.. This output is fed to a 2nd switchng supply to generate all the voltages the amp actually uses, which could be any number of voltages (as the amp circuits require). This would be a serious case of 'design-overkill' for a guitar amp, it's usually used in aerospace stuff....

Alternatives:

- Rent one of those real super-quiet Yamaha gas-engine electric generators and a 100 foot heavy-gauge power cord to go with it.

- Get a Rockman or Sansamp and record direct out of that.

- Get a Rat Shack FM generator and use your car's FM radio as the amp.
________
Starcraft 2 replays

[puls]

The crate taxi & limo amps can be run off a cigarette lighter from a vehicle. There's another smaller one in that series, but I can't remember what it's called. Then there's pignose amps, most of which can be run off of batteries. Any amp that runs off of batteries could easily be run off of a car battery. May need a step-down transformer though.

hope that helps

jwp