... and, of course, how load it is depends not only on the amplifier power but also on the sensitivity of the loudspeakers. My (old but wonderful) Tannoy Berkeleys are very sensitive and at anywhere near their maximum handling capacity of 85 watts are absolutely deafening.
85 watts into more modern, compact (but much less sensitive) speakers won't be nearly so loud. (that's all RMS watts by the way)
loud! (I fixed most of them but missed that one)
My friend is obsessed with sound quality. He took his favourite music into a store and played it to choose a stereo to buy. The one he was recommended by the salesman he immediately dismissed as it sounded distorted when he played heavy metal at full volume.
One thing I disagreed with him on was if it should sound good when turned up to max. He insisted if it overloaded the amp or speakers, the volume control shouldn't go that high. I suppose it makes it more convenient if you don't have to decide where to stop, but it also means you can't turn it higher if you're trying to listen to something really quiet.
Yes loud! What? LOUD!!! It's too loud to hear you!
Are you familiar with the sine wave?
Music power is different from RMS in two important ways. Firstly, if you put a square wave into an amplifier with a given rail voltage, you will get twice the power out if it compared with a distortion free sine wave. Guitarists do end up putting what amounts to near square waves in... Secondly the power supply itself may bot be able to sustain full voltage fpor very long, and the music power again represents how the amplifier will handle short duration transients
Naturally since the Numbers are Bigger, that;s what the marketing will quote, except in high end kit where people are more in favour of truth than bullshit, and power supplies are well designed.
I know! ;-)
I did my AC circuits theory at technical college.
It doesn't tend to happen nowadays, but back in the 1960s, it was fairly common to see UK low-end guitar amp ads mentioning "peak power" at twice the RMS power. This was a marketing move, of course.
In the USA, RMS was rarely referred to (in fact, output power was not often mentioned by some respected makers, who preferred to talk of "n tube performance" as though every valve contributed to output power) and sometimes even compared peak power with "British watts", presumably trying to make imported Vox and Marshall amps look puny.
Wasn't this subject done to death about half a century ago?
Practical Wireless coined the term 'WFT power'.
WishFul Thinking.
Yes but if you're measuring power correctly, you can't get more out than in. Power is power, end of story. I guess you need a true RMS meter.
Shut up woman.
I am sure it was.
My point being, as a then audio engineer designing high power amplifiers for hifi and PA as well as guitar use, there is *some* merit in it.
In particular the wonderfully cheapskate British (valve) guitar amplifiers of the 1960s and 1970 were capable of extremely loud 'attack' sounds, before the cost reduced power supplies sagged back to the RMS power figure (times two, on account of the total overload).
In short, a 100W RMS Marshall was subjective louder and had more 'attack' than an equivalent 100W RMS transistor amplifier.
Also the softer overload meant that you could get even more out of it for a given level of distortion
I never knew Marshall was British. A rare thing - decent British products.
Seems they still use valves too! Have we really not developed transistors as good as valves?
Valves can withstand considerable overloads briefly, trannies can't. Plus overdriven valves tend to sound nice enough, trannies not.
To the extent that one of the many guitar pedal effects was a simple non-linear diode device to simulate valve distortion.
That is not entirely correct. In general, valves being expensive, valvea amplifiers tend to have less feedback than transistors. This leads to softer 'clipping'
That diesnt mean that they can overload more, just that they are not as harsh as when they do.
All modern amplifiers feature something of that nature in the 'overdrive' channels.
We had a couple of home made cabinetted Tannoy 15 inch monitor gold's many years ago for a rather upmarket sounding disco and very good that was too!
Driven by a water cooled QUAD 303 power amp:)
Well IIRC it was the hot summer of 1976 and it the amp did get u hotter then to ought to have done so it was often placed with its fins in a bowl full of cold tap water! it worked very well the amp, made in 1967 is still here in daily use!..
Yes it ought to have been air cooled but it was very hot and sweaty in most locations so the water cooling was used!
How did that not short it out?
P.S. WTF? "it the amp did get u hotter then to ought to have done"
Ive had similar transistors; heat sinks over 100°C...
Try Botswana discos Tony. Now THAT is hot and sweaty!
What body parts did you notice were sweaty?
thus valve amps sound nicer than trannies when pushed
the fact that valves can be peaked harder is down to a few of their physical properties. You ought to know what ones.
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