What Does The Program Mean

Discussion in 'Amps and Cabs [BG]' started by Icarus26, Jan 10, 2009.

  1. Icarus26

    Icarus26 Guest

    Jul 21, 2008
    Anaheim, California
    Quick question fellow TBers. I've been doing some research on cabs and heads since i'm looking to get those instead of a new bass. Since i've never owned or looked at cabs or heads before, i was just wondering what the program wattage was? So if someone could tell me what that stands for, it'd be a real help.
  2. bongomania

    bongomania Supporting Member Commercial User

    Oct 17, 2005
    PDX, OR
    owner, OVNIFX and OVNILabs
    It actually is meaningless. There are a few different ideas of what it is "supposed to" mean, but every manufacturer interprets and tests it differently. The unfortunate truth is that you have to just ignore it as a meaningless spec.
  3. Be interested to know this too, what are the different ideas about what it is "supposed" to mean? Is it sort of like peak (transient) max power handling capability?
  4. rbonner


    Sep 25, 2008
    Naw, its 2 times something usually. Looks really good in marketing materials. BOB
  5. T-Bird

    T-Bird Guest


    Or three times nothing ;).

    Really, for me anyway, Program power=Music power=ignore

    Continuous RMS with THD% and frequency is closest to the "truth" and can be compared to a degree.

  6. bongomania

    bongomania Supporting Member Commercial User

    Oct 17, 2005
    PDX, OR
    owner, OVNIFX and OVNILabs
    I believe the main idea is that it's some level of power (maybe a maximum) sustained over a longer period of time (undefined) with the word "program" meaning "musical content" like a band mix rather than a test tone. So I think it is supposed to mean like "this amp can put out this amount of wattage of loud music over some time"... but again it has no value in reality.
  7. heavyhitter


    Jan 24, 2008
    Yea what Bongo says.......Ignore it and look for RMS, its just marketing BS.
  8. rbonner


    Sep 25, 2008
    Well see Music and Program power is different than pink noise tests.

    If you read all the crap on say the Crown website they discuss this stuff. Their tests have to do with the ability of an amp to make power and dissapate waste heat. The inefficiency ends up becomming heat that needs to go somewhere.

    Anyway, with a solid tone of say 1000Hz the duty cycle is 100% so if the amp makes 1000W out, that is solid contiuous 1000W of pure output smoke. The waste heat on a 50% efficient amplifier would be 1000W plus whatever the power supply already loses, that's a lot of heat to pull out of a box.

    Pink noise is a high duty cycle test but has output over the whole range of audio spectrum at once a real roar... I can't remember the duty cycle of pink noise. Maybe 50%, Maybe 30%.

    I remember we used to do these tests on esoteric HIFI gear to set the graphic equalizers for room acoustics... I always hated that, probably why I have hearing loss, that or my fricken wife yelling at me for 32 years. Have complete signal loss at her voice freq now, bitch.

    OK well Crown states Program or Music power is a 1/8th duty cycle situation... so compared to a solid tone at 100% music makes a 12.5% load on the amp. We bass guys know this difference as headroom, as we can hit our amps to peak with our notes but they are just notes, the time between those notes allow the amplifier to cool.

    The industry determines this as the 12.5% duty cycle. Oh and music isnt constant full power, its full of peaks and valleys of power demand.

    OK so when it comes to speakers its the obvious reverse of the amplifier, where the amp can only put out X amount of power no matter what the duty cycle is, it needs to cool itself... A speaker needs to take power and survive.

    RMS is .707 of watt, a watt is voltage times current in a DC circuit, RMS is the AC equivellent. peak 1.414 a watt and peak to peak is 2.828 times so you have RMS, Peak and for the guys who want big number they list PEAK TO PEAK. Which is like saying the distance from LA to NYC is 6000 miles, we'll dumbpoopie you have to go home dont you? This compares to a SPEAKERS X Damage + and - Millimeter numbers.

    SO now you know Program or Music power is 2.828 times a DC watt, RMS at .707 is the AC equivellent and is just a calculation and peak is da peak. And RMS is reasonable and can be compared between equipment...

    Except solid state amplifers and tube amplifiers where a tube can make a peak and survive a transistor cannot. So you find about a 1/3 to 1/4 ratio of SS power to tube power. A watt is a real thing and is not SS watts or tube watts.

    But tube RMS watts of say 300W to 400W compares very nicely to say an SVT-4PRO's peak to peak output rating of 1200W.

    Hopefully I didnt get to lost here, as I really dont care right now.

    See what I mean?
    See what I mean?
  9. Jim C

    Jim C I believe in the trilogy; Fender, Stingray, + G&L Supporting Member

    Nov 29, 2008
    Bethesda, MD
    Nicely said on all topics Bob.
    Always enjoyed the 70's guitar amp ratings when a 50 watt transistor Japanese amp vs a Marshall showed that there really is no standard. Same with Trace Elliot vs many modern amps. Watt for watt, the Brits amps are way louder IMO.

    Seems like RMS is all you can evaluate with.
    The only way I have been comfortable evaluating audio gear regarding transient reponse is to use it in a real world setting.
    Have seen some PA speakers and studio monitors claim very high SPL levels but distorted badly with dynamic program material; produced a 1 K tone nicely though. :rollno:
  10. rbonner


    Sep 25, 2008
    Hi Jim, yes nothing like an SPL of 137DB that sounds like an airline jet crashing into the ground. No man, thats Whole Lotta Love by Zepplen mannnn.... Far OUT... BOB