I am getting ready to install my empeg in a portable venue where I will listen through headphones, powering the empeg by means of a small 12V motorcycle battery. No amplifier or speakers will be connected.

What is the average power consumption of the empeg? I have plenty of "headroom" for starting the hard drives without voltage drop, but under typical use, how many watts does the empeg consume? If I turn visuals "OFF" does that significantly reduce power consumption, or do the VFD heat filaments continue to draw their one-watt (or more?) load even when the display is blank?

The empeg will be subject to low-amplitude vibrations primarily around 5--50Hz, never even approaching the 150g maximum the hard drives are rated to resist while spun up. Probably an order of magnitude less. Visualize the maximum shock as being about like tossing the empeg onto a soft bed. These maximum impacts might come several times an hour. The 5--50Hz vibrations will be more or less constant.

So now the question: what effect will these low amplitude vibrations (probably equivalent to placing the empeg on the above mentioned soft bed and then drumming your fingernails on it) have on the hard drive?

tanstaafl.


"There Ain't No Such Thing As A Free Lunch"

C'mon, tell us! Where the heck are you planning on taking your empeg??

Maybe we should add a feature request for a headphone socket, since it is "not recommended" to plug headphones directly into the audio outs :-)

(list 6284, Mk1 S/N 00299 4GB blue [for sale]. Mk2 S/N 080000094 6GB blue)

C'mon, tell us! Where the heck are you planning on taking your empeg??

Yeah, Doug, you need to give them all of the relevant information.

(He's putting it on his bicycle, by the way).

___________
Tony Fabris

A bike that definatly wins the smallest vechile to have an empeg installed. Bet it will be an arse to find somewhere for the sub.

A bike that definatly wins the smallest vehicle to have an empeg installed

Actually, I am aiming to be the uncontested champion of the "Strangest Places for an empeg" thread (see here ).

In the summertime I commute 10 miles each way to work on my bicycle (see attached photo), and I miss having my empeg with me on the commute.

The empeg will install on a platform mounted to the crossbar at the top of the handlebar arch. I have some oddly-shaped foam rubber that will provide very progressive shock absorption, and the empeg is completely shielded from the weather by the windshield which extends further backwards than is apparent from the angle shown in the picture.

Maybe we should add a feature request for a headphone socket, since it is "not recommended" to plug headphones directly into the audio outs :-)

The empeg WILL power a good set of the small walkman-style inside-the-ear headphones directly from the lineouts. With the headphones I use (made by Optimus, $25 or so from Radio Shack) the perceived volume at a given level setting is almost exactly the same as in my car. So 0dB is as loud as I care to listen in either case. Cheaper walkman-style headphones don't do as well, and "regular" headphones require too much power to work this way at all.

I listen to my empeg all day long at work through my headphones.

But... to repeat the question: who knows what the average power consumption is? Who knows whether my hard drive will be happy in this somewhat un-gentle environment?

tanstaafl.



"There Ain't No Such Thing As A Free Lunch"

Edited by tanstaafl. on 05/06/01 11:44 PM.

Even if someone gives you power and G ratings for the empeg, they're not going to mean much "in practice". Personally, I think you should just try it and let us know how it goes.

Worst that could happen? Your hard disk goes bad after a month. Hard disks are (relatively) cheap these days. If you keep the MP3s on your PC's hard disk, then there's no loss there if you have to buy a new disk. Besides, with the temperatures the way they are where you live, I think your hard disk is in jeopardy as-is, so you haven't got much to lose.

And if the battery doesn't cut it, well, then you've only lost the amount of time it took to make the mounting assembly and try it out. In the meantime, it would have been a cool thing to try and we could all learn something from it.

I say go for it. All I ask is that you document the installation with photographs.

___________
Tony Fabris

I'd say (with absolutely nothing techy to back me up) that if my empeg hard drives have lasted as long as they have in my Civic with the shocks as stiff as they are, you should be fine. I regulary encounter potholes in San Francisco that nearly blow my tires and knock the empeg almost out of the bay.


|| loren.cox ||

PS: PLEASE document your work on that install... i have to see this!!!

PLEASE document your work on that install... i have to see this!!!

It won't be much to look at. Pretty crude, actually: just an empeg sitting on top of my handlebars. (It'll be strapped to a foam-covered piece of plywood which will be secured to the handelbars with four hose clamps) It'll look neat and clean enough, but there's nothing high-tech going on.

But yes, I will post pictures if I can find someone with a website willing to host them (hint, hint...)

And I have a request for a bit of help. If someone (in the US; overseas would be too much trouble) has a dead power brick of any kind that has a cord with the 2.1mm center positive plug on the end of it, if you could cut that cord off and stick it in an envelope and send it to me I would appreciate it. Otherwise I will have to sacrifice my spare power brick. :-(

tanstaafl.



"There Ain't No Such Thing As A Free Lunch"

can't you buy just the plug at radio shack or order it from MCM or mouser or something

Remember, you'll need a blank plate to put there so nobody breaks into your bike to steal your stereo while it's parked.

-Zeke

just say you weren't paying much attention...

I've done some quick power usage measurements for you.

At 12VDC the unit draws an average current of 503mA (6.036 watts). This was the average current measured over a 30min period with the unit playing. The filament heaters run whenever the player is running. The difference between no visual and the funnelweb visual is approximately 30mA, the visual seems to run even when not visible (select no visual to minimize current). But for a saving of 30mA it's not worth it. I was using line out to an amp, driving headphones will add a few mA but again not enough to worry about.

I don't know what size battery you were thinking of but a 12 volt 3.4 amp hour battery will give APPROXIMATELY 3.39 hours (3.4 * 0.5 / 0.503). The 0.5 is to allow for the fact that most SLA batteries are rated at the 20 hour rate, the empeg's cutout voltage and for a bit of headroom.

Also the player only turns the display off when it is in standby, the majority of the circuitry is still active ~225mA.

Rod.

g, not G.

One of the few remaining Mk1 owners... #00015

...and I've been running mine in my Mini since I bought it, which is world reknowned for lack of shock absorption. A bicycle is unlikely to be a problem

One of the few remaining Mk1 owners... #00015

The empeg will install on a platform mounted to the crossbar at the top of the handlebar arch.

Make sure it's not too far tilted from horizontal. The shock ratings of the drives (and the usefulness of our own shock absorbers) apply only if the drives are close to horizontal.

Peter

Something to keep in mind: The empeg is designed to be mounted in a roughly horizontal position (actually tilted 8 degrees with the front end up) for the unit shock absorbers to function properly, so if you can get close to that, you will get longer hard drive life.

Then again, I wouldn't worry to much about it. About a year or so ago, I rigged up an entire computer (with regular hard drives, no shock absorbtion) in my trunk/boot on an DC/AC inverter set to load winamp w/o a display, and I could control the thing with just a numeric keypad. I had it in there for about 6 week, hitting potholes and stuff with no problem.

- John

Ah, you beat me cause I type slowly!

I had a salvaged 12v 12ah ups battery that had been sitting on the shelf in an unknown state of charge for a year or so, I had used it to test a headlight and it was on the dim side. The battery sat for another year, and was abused by our techs in the normal ways (screwdriver across the terminals, etc). The sparks were pretty weak by then and it wouldn't run my 120v power inverter anymore so I decided to run the empeg off it just to see how long it would last in it's diminished state.

Result: the empeg ran for about 6 hours the first day, then when I hooked it up the next day it ran another 4-5 hours before hitting the powerfail sequence when the drives spun up.

I'd bet a good LI-on laptop battery would last at least 2-3 days if not a week of commuting between charges and be a good deal lighter than the motorcycle battery.


YMMV, quite literally :)

A bike that definatly wins the smallest vechile to have an empeg installed.

Now what's really needed here is a ruggedised, waterproof disc-based MP3 player that mounts in a bottle-cage, like the batteries for posh headlights do.

Hmmm...

Peter

Just when you thought the world of empeg couldn't get much stranger.
Along comes this

but seriously how about getting another cage and tacking on some jubile clips of the stainless type

In reply to:

---

Now what's really needed here is a ruggedised, waterproof disc-based MP3 player that mounts in a bottle-cage

---

Oh great. That's all we need. So not only would we have to contend with dozy-pr!ck cyclists who somehow think that traffic lights don't apply to them, ride on the pavement at every opportunity and generally try and kill themselves, but we give them a pair of headphones so they can blast themselves with music and cheerfully block out useful road noise (like the air horn of an on-coming HGV) into the bargain. Wonderful.

I shudder to think what the list of warnings and disclaimers would be on that product.

Nicholas.

PS I'm not saying that all cyclists are dozy pr!cks and I'm not saying that under all circumstances it's dangerous to have headphones on when you're cycling, but......

--
18GB red s/n 080000299, original pos'n 8724. Reproduction of this post is not permitted.

Now what's really needed here is a ruggedised, waterproof disc-based MP3 player that mounts in a bottle-cage, like the batteries for posh headlights do.

Been there, done that. My current lighting system uses a six-volt 4.5 Amp-Hr lead-acid gel-cel battery that I put into a standard water bottle (cut the bottle in half, inserted the battery, glued the bottle back together) and it resides in my bottle cage. Don't know if I can find a 12V battery of the same physical size, though... There are lots of options there.

tanstaafl.

"There Ain't No Such Thing As A Free Lunch"

contend with dozy-pr!ck cyclists who somehow think that traffic lights don't apply to them,

This may be a surprise to you.... but I agree 100% with what you are saying here. I would estimate that at least 90% of all cyclists (in the US, anyway) ride like complete idiots.

[soapbox] My riding style is to act like I am a small car. That means full stop at all stop signs, obeying traffic lights, when riding in city traffic (where I can maintain the same speed as the cars around me) I take my space out of the middle of the lane so there is no confusion about where I am going and no problems seeing where I am. I never go through an intersection (where I have right-of-way) without making eye contact with opposing drivers.

I watch other cyclists paying no attention to what they are doing, riding without helmets going the wrong way on one way streets... and I just cringe and know that their actions are going to cause the motorists they encounter to show hostility to the next cyclist they encounter -- possibly me. [/soapbox]

Your point about headphones is well made. When I wear them I don't play them loud -- I like to hear what's going on around me -- and I do ride with mirrors on the bike.

tanstaafl.



"There Ain't No Such Thing As A Free Lunch"

Make sure it's not too far tilted from horizontal.

I plan on mounting it as close to 8-degrees up as I can to make the drive platters absolutely horizontal. I had already given thought to that...

tanstaafl.

"There Ain't No Such Thing As A Free Lunch"

Remember, you'll need a blank plate to put there so nobody breaks into your bike to steal your stereo while it's parked.

ROFL!

can't you buy just the plug at radio shack

Prob'ly... I just thought if someone had one they were going to throw away anyway...

tanstaafl.

"There Ain't No Such Thing As A Free Lunch"

I'd bet a good LI-on laptop battery would last at least 2-3 days if not a week of commuting between charges and be a good deal lighter

You're probably right, and the voltage drop curve would be more computer friendly as well. But... a $25 gel-cell vs $150 Li-Ion is a pretty compelling argument.

tanstaafl.

"There Ain't No Such Thing As A Free Lunch"

I've done some quick power usage measurements for you.

And thank you very much. This is exactly the information I was looking for.

I have acquired a 5 Amp-hour 12-volt gel-cell battery (probably used for emergency lighting system, maybe an alarm system?) for $25. This should give me about 6 hours of listening time, except that I won't want to deep-cycle this battery (lead-acid) so I'll re-charge it daily. Hopefully this weekend I'll have it all together.

Thanks again for the information.

tanstaafl.

"There Ain't No Such Thing As A Free Lunch"

I've had my Mk2 in an 86 Bronco II in urban potholes, rural offroad & even the interstates at 65mph (posted) that have potholes that make you cringe & throw the vehicle sideways making you wonder how the tires didn't blow or break loose & have knocked the empeg out of the sled. All in all the empeg is built pretty tough for what it is, my vehicle is not gentle on it by any means. No weird or screeching noises yet.

#695 Mk2GRN& a mere 12Gig
"What, me be sorry"