There is a guy selling an Avatar 8ohm cab with 2 50W Private Jack speakers in it. My question is, Does the cabinet need to have a higher wattage rating than the amp? I read online that when distortion is added you need to multiply the amp wattage by 1.41 or something. They claim that the amp's stated wattage is based on "clean power" and that adding distortion changes the formula.
I have a 100W QR on order and was thinking of adding a second cabinet to my setup...
I have never ever every heard that before. Who is 'they'?
I mean how do you multiply the amp wattage anyway? Besides, every manufacture (speakers or amps) has slightly different ideas about how they rate their gear for clean headroom before it distorts. Ohms are ohms and watts are watts. Just match.
The only way you ever run into a problem with watts would be if you had a 100 watt amp that was SIGNIFICANTLY under rated (meaning it actually cranked out 150 watts) and a 100 watt cabinet that was SIGNIFICANTLY over rated (meaning it actually could only handle 75 watts). 150 watts pumping into a 75 watt cab at full volume for an extended period would be bad.
That scenario is very very unlikely. If you buy a 100 watt cab it can actually probably handle a fair bit more. They (speaker manufacturers) do that on purpose.
You'll be fine if you buy that Avatar cabinet you mentioned. If you still have a question - ask Dave at Avatar. He runs the company. Great guy.
OK. Yeah...I've read similar things too. That might be true for a 10 watt tube amp but if you remember that we are actually talking about RMS in relation to watts then it starts to get cloudy. Also, remember that speaker manufacturers often (read: almost always) rate their speakers much lower than they actually are. A 70 watt Vintage 30 can probably handle more than 70 watts. So a speaker labeled with 10 watts of RMS can probably handle 15 or 20 watts I'm thinking. Before RMS (root mean square) was introduced by the government to try to level the playing field of amplification and loud speakers it was even crazier.
There is actually a study done by (see wikipedia article) that suggests that an amplifier might well be matched with a speaker/cabinet that is 2 to 3 times the capacity of that speaker/cabinet. I think the idea here is that guitar speakers are supposed to distort and sound good with electric guitars. You don't want a speaker so clean that it doesn't add any tone or color. Make sense?
If that is what someone is after then by all means get a speaker/cab that is double your amp's output.
Also keep in mind that people rarely max their amps to capacity. Power tube distortion is not the greatest distortion for most genres (but not all obviously).
AND - there tons of other variables too like transformers, circuit design, output of pickups, cabinet constructions, tubes used, magnet sizes, etc etc.
So....my advice is always to match as best as you can. Dangerous to go less than the amp. OK to have more speaker watts than amp watts but you get to a point of diminishing returns if your speaker is so efficient and clean that you end up with no speaker 'voice', then you have too much speaker watts. For example, modeling amps and HiFi amps like high speaker watts as in those cases you don't want speaker breakup or distortion.
PS: not a tech here....just rambling
Last Edit: Apr 11, 2016 21:41:24 GMT -5 by splawndude