Philips Xtreme Power H4 VS. Philips Xtreme Vision H4

Wurkkos

Lightdoctor

Enlightened
Joined
Feb 21, 2010
Messages
389
What are the performance differences between these two lamps? Philips claims a 20% improvement for the XV. Are they really worth the extra dough, compared to the XP?

Thanks.
 

-Virgil-

Moderator
Staff member
Joined
Mar 26, 2004
Messages
7,614
You know the drill: More light and better beam focus and less lifespan as you move up from long life --> standard --> +30 --> +50 --> +80/90 --> +100 etc.

I haven't plotted it out or anything. I might pick the Xtreme Vision if I needed to get the maximum possible output and beam focus out of an H4 headlamp, but then again I might pick the Xtreme Power in 9003/HB2 instead, because the 9003/HB2 filament precision specs are tighter than H4, which means beam focus is better with an HB2 than with an H4, in general. But that said, I think the Xtreme Vision might be past the reasonable center section of the cost/benefit curve.
 

Lightdoctor

Enlightened
Joined
Feb 21, 2010
Messages
389
Thanks SWM, your answer is what I was thinking...just wanted to hear it from someone else too.

Sorry, I don't like the Osram NB...it's OK in my book, but I wouldn't go out of my way to buy one.

I'm currently running with the Osram Rallye 70/65 H4...great lamp if you don't mind spending $22 ea for them and having them last for only 9 months or so.
 
Last edited:

-Virgil-

Moderator
Staff member
Joined
Mar 26, 2004
Messages
7,614
You'll get similar lifespan out of the Xtreme Power or Xtreme Vision bulb (or the Night Breaker, for that matter).
 

Lightdoctor

Enlightened
Joined
Feb 21, 2010
Messages
389
I know...I can get a set of XP's for about the same price for one of the Osram Rallyes...this seems to be a better value when compared to the other choices.
 

Qship1996

Enlightened
Joined
Jan 30, 2010
Messages
460
I'm currently running with the Osram Rallye 70/65 H4...great lamp if you don't mind spending $22 ea for them and having them last for only 9 months or so.

I got 2 years/ 50,000 miles out of my last set of Osram 70/65 bulbs........currently on the 11th month with the Osram 85/80,with a Rallylights harness, so certainly not starving for voltage either.
 

-Virgil-

Moderator
Staff member
Joined
Mar 26, 2004
Messages
7,614
Wow, Qship, that is wayyyyyyyyyyyyyyyy off the right side of the bell curve! How much actual usage do you put on these headlamps? Most people don't get anything like that out of them.
 

TEEJ

Flashaholic
Joined
Jan 12, 2012
Messages
7,489
Location
NJ
If most of your driving is during the day, you get more miles/years out of your headlamps.


:D
 

Qship1996

Enlightened
Joined
Jan 30, 2010
Messages
460
at 2 hours/day, 9 months would be 540 hours, 3 hours/day a total of 810 hours of use, 4 hours/day a total of 1080 hours lifespan.........still VERY,VERY respectable for that level of performance bulb.I dont think you will find a tradeoff of any longer life without seriously compromising the bulbs performance.{like a long life type bulb}
 

-Virgil-

Moderator
Staff member
Joined
Mar 26, 2004
Messages
7,614
Let's do some math. All of the bulbs we're discussing here have a Tc lifespan of between 150 and 250 hours on low beam at 13.2v. Tc is the hour figure at which 63.2% of a test batch have failed. Lifespan changes exponentially to the power -13 (negative 13) with voltage change, and if you have a relay harness you're feeding those bulbs considerably more than 13.2v. You're likely feeding them at least 13.8v, probably closer to 14v.

13.8v would drop a 200-hour-at-13.2v lifespan down to 112 hours.
14.0v would take the figure to 93 hours.

ALL of these lifespan ratings are with zero vibration. Vibration and mechanical shock greatly decrease lifespan.

2 hours/week means you'd get 100 weeks (about 2 years) out of a 200-hour bulb operated at its rated voltage and subjected to zero vibration. It would mean 50 weeks (just shy of 1 year) at 13.8v, never going above that voltage, and again subjected to zero vibration.
 

Qship1996

Enlightened
Joined
Jan 30, 2010
Messages
460
So how am I getting 2x that life on the osram 70/65 and Lightdoctor getting WAY more than I ???? Sterns site says rated life is calculated at 14.0 volts, not 13.2 ???? which would be the only explanation I can think of.
 
Last edited:

-Virgil-

Moderator
Staff member
Joined
Mar 26, 2004
Messages
7,614
US bulbs (HB1, HB2, HB3, HB5, 1157, etc.) are mostly rated for output at 12.8v, lifespan at 14.0v. ECE bulbs (and European-made bulbs that don't conform to ECE R37, such as the 70/65w and 85/80w items) are mostly rated for output and lifespan at 13.2v. Your unusually long lifespan is inexplicable so far. What's your bulb operating voltage with the harness?
 

Qship1996

Enlightened
Joined
Jan 30, 2010
Messages
460
Funny you should ask about voltages,because I was so curious,I just came back from a quick drive with the VOM ! I did not measure voltages at back of bulbs{on my car you have to actually remove the headlamp to get to the connector easily} but I measured voltages directly at the battery- got 14.34 at cold startup and it settled at 13.65- 13.7 after a few miles driving. Not sure whether the 14.34 startup voltage is due to a cold alternator or specifically designed to put out a higher voltage to quickly replenish battery after starter operates?

PS the alternator is original, and has 286,180 miles on it!
 
Last edited:

-Virgil-

Moderator
Staff member
Joined
Mar 26, 2004
Messages
7,614
Temperature-compensated voltage regulation has been standard on most vehicles for many decades. Internal resistance of a battery is higher at colder temperatures, so charge voltage must be higher. System voltage at the battery looks quite normal, but the answer to your question about bulb life won't be found without a measurement of voltage at the bulbs with the engine running, the headlamps turned on, and both headlamps connected (no pulling the socket off), then a measurement at the same time across the battery.
 

Qship1996

Enlightened
Joined
Jan 30, 2010
Messages
460
more work than I am willing to do at the moment considering I am happy with the life I am getting out of the bulbs!! Well, we at least know the bulbs are not getting MORE voltage than I measured,and probably a little less due to the extra length of wire & connections in the harness,but the harness is only 1 year old and quite heavy duty{12 & 10 gauge wire, 3 40 amp relays}} so I would not expect a huge drop.

Still puzzled how Lighdoctor is getting WAY more hours{540-1080 hours} than even I am getting from the same bulbs.....maybe he can easier measure actual voltage at bulb connector and let us know the results!



******* DUH, it just dawned on me that when I ran the Osram 70/65 bulbs for 2 years, it was on the factory wiring- I installed the Rallylights harness 11 months ago when I installed the Osram 85/80 watt bulbs********
 
Last edited:

TEEJ

Flashaholic
Joined
Jan 12, 2012
Messages
7,489
Location
NJ
What's the sigma for bulb life?

IE: What's the potential RANGE of life you'd project?

There are sometimes salients/outliers in a batch, that are just at the long or short ends of the typical bell curve...

..and, is it possible that 2 hrs a week is easier on a bulb than 2 hrs a night, or that one drive uses high or low beams more than the other?
 

Latest posts

Top