Confused about stuff

[Nakatomi]

Most of you are familiar with me by now. I'm a 'bit of a geek'. I know stuff about electromoronics & electrickery & am a bit of a dab hand at fixing stuff.

BUT.. !

I'm still having a hard time understanding amplifier & active speaker specs - or more to the point I'm puzzled by what seems to be going on in the world of speaker specs. Manufacturers lie.. er I mean bend the truth (that's called MARKETING, deary) - I've known this for ages but by how much, and why precisely? Not that it really matters a jot but I'm interested in knowing what the real power output is. You know. Just because.

It was Yamaha who first piqued my interest when I was perusing their spec sheets. An active speaker which apparently (on paper) goes very loud (oo - and recently confirmed when I heard them in person) with "1300 watts". Ah yes but look at the figure for power consumption - as in what it pulls from the wall. ONE HUNDRED WATTS. Hmmm.

The speaker in question was a DSR115A. I didn't happen to like the sound much, FWIW but that aside.. I found a this (https://www.youtube.com/watch?v=0Lx3_pi6cic) video in which John Young of the Disc Jockey News hoof said speaker to limiting point while measuring the power it pulled from the wall with a Kill-A-Watt meter (plugin power meter). It peaked around 100 Watts.

Yes yes yes, I know full well that power is meaningless in these terms. It's really all about how loud it is (ie is it man enough for the job at hand) and what it sounds like. I know. But it's been bugging me that specs seem to be so far out of kilter with real world figures.

A comment on the above video asks "so where did the other 1200Watts go, John?", to which he replies something like "it's a different kind of watts". Hmmm. Not a good answer IMHO. OH yes! Their made up watts vs real world watts you mean? Ahhh..

At a group speaker test night a while back I'd intended to measure the power drawn from the mains so we could compare them but I couldn't find my meter in time for the event.

Intriguing, don't you think?

[DJWilson]

We have Lumens for the strength of a lamp @ 2m, 5m etc. It's a shame we don't have something similar for speakers.

Surely the only real 'power level' is the Db it knocks out? But again, there's no standard test with distances, duration etc.

[Nakatomi]

Some enlightened manufacturers state how they arrive at their output dB figures as I think I've said. This only tends to happen on high end gear though - eg 126dB @1m, half space....

A figure of 126dB for a speaker costing upwards of 2 grand I can believe - not 133dB for a cab costing under 800 quid! I've met 124dB once or twice in my life & it's safe to say that was from a set of speakers I could only ever dream of owning/carrying/transporting.

There are a few outfits on youtube doing empirical measurements (with frequency response plots too!) but they sadly don't cover many models of PA.

One day soon I might actually start measuring speaker power output. If only to satisfy my own curiosity

[Excalibur]

And before long, some white haired old fogey is going to come along and point out that in The Good Old Days, the amps only claimed to output 100watts, but with a couple of 12" cabs we could play venues we take 5Kilowatts of line array to nowadays. :whistle:

Mind you, that was before they devalued the Watt.*


Re your " magic " Yamahas, the only thing I can offer is that music is transient peaks, and thus you're not measuring constant unremitting current. I know that doesn't answer your question, but it's got to have something to do with it.

* Devaluing the Watt. They didn't. It's just an old, old joke among old, old DJs. :D

[Nakatomi]

And before long, some white haired old fogey is going to come along and point out that in The Good Old Days, the amps only claimed to output 100watts, but with a couple of 12" cabs we could play venues we take 5Kilowatts of line array to nowadays. :whistle:

Mind you, that was before they devalued the Watt.*


Re your " magic " Yamahas, the only thing I can offer is that music is transient peaks, and thus you're not measuring constant unremitting current. I know that doesn't answer your question, but it's got to have something to do with it.

* Devaluing the Watt. They didn't. It's just an old, old joke among old, old DJs. :D


Re the 'magic' yamaha I realise that 'music powrr' or similar is at play here but what's amusing is that the real power seems to be around 100W rms :rofl:.

Could it really be, and Watts haven't really been devalued? ;)

Now those plugin meters aren't known for being pinpoint accurate but... There's a 13x discrepancy to account for

[ppentertainments]

Surely the only real 'power level' is the Db it knocks out? But again, there's no standard test with distances, duration etc.
And no matter where I measure my 130db (or there abouts) speakers won't deliver over 90db lol

[Daryll]

The the age old story , people are blinded by numbers.
I have a old Vox AC30 , that will blow most 1K systems out the door ( I dont advocate using a AC 30 for DJ work , Two...........yes...lol)

Daryll

[Excalibur]

The the age old story , people are blinded by numbers.
I have a old Vox AC30 , that will blow most 1K systems out the door ( I dont advocate using a AC 30 for DJ work , Two...........yes...lol)

Daryll

Tens of years ago, I did a disco where I augmented my disco sound with a Woolworths ( Yes, Woolies! ) 50w guitar combo. The reviews of the disco afterwards were that is was exceedingly good, but it was :Censored:ing loud!

They don't make Watts like they used to. :D

[ukpartydj]

Inflation?

I've done the power meter speaker test and found it truly bizarre also. I've got a pair of studio monitors rated at 50W each, with no music playing they have about 60W power draw, when music is playing fairly loud, it goes to about 70W (from memory, could be slightly off). So it's about 70/100W which sounds about right.

My PA system rated at 1500W RMS takes about 240W at normal levels! Hilarious! Probably looking at 350W full power! Very odd that my lights say 80W power draw and they draw 80W! What's going on!

[rth_discos]

Out of interest, what difference does watts make anyway?

I've always taken the view that the size of the cone is going to make the biggest difference.

My Maui 5s are about the least powered speakers I've seen (200w rms) yet they pack a punch that I feel would out perform cheaper, higher wattage speakers!

Anyway, for me, the 'sound' of the speakers is a more important than the 'loudness' (who wants bad sounding, loud speakers?!). And sound quality can't be measured in watts or dB.

[Excalibur]

My Maui 5s are about the least powered speakers I've seen (200w rms) yet they pack a punch that I feel would out perform cheaper, higher wattage speakers!


Correctamundo. Baffles me too. :confused:

[mattydj50]

A Watt, unit of power in the International System of Units (SI) equal to one joule of work performed per second, or to 1/746horsepower.

So, all I need now is 746 horses.

[Nakatomi]

Out of interest, what difference does watts make anyway?

I've always taken the view that the size of the cone is going to make the biggest difference.

My Maui 5s are about the least powered speakers I've seen (200w rms) yet they pack a punch that I feel would out perform cheaper, higher wattage speakers!

Anyway, for me, the 'sound' of the speakers is a more important than the 'loudness' (who wants bad sounding, loud speakers?!). And sound quality can't be measured in watts or dB.

Watts don't really make ANY difference to the loudness. If you had a one watt amplifier & rigged it up to a speaker with 120dB per w sensitivity you could have 120dB one metre away from the speaker with only ONE WATT driving it :)

No, I'm just baffled why specs have become such big lies.

It's perfectly feasible that a PA system pulling a mere 250W from the wall is amply loud enough for a given application (though I doubt a concert at a stadium :D ) - so why do manufacturers see the need to LIE so much? Who started this lying war? It's undoubtedly purchasers of said gear provoking it further IMHO.

I got to thinking - wouldn't it be massively cool if there was somebody out there measuring & recording speaker specs by exactly the same yardstick for all to see & compare? Damn right it would be!

[Benny Smyth]

And sound quality can't be measured in watts or dB.

Try telling that to the absolute 'tard in Currys a few years ago when I went there to buy a new surround sound system for my living room.

"1,000 Watts of sound - that means the quality is amazing!"

"You measure sound quality in Watts?"

"Well, obviously you won't use all 1,000 in your living room. You'll only use about half of that, and it's the extra headroom that gives you the best sound quality."

"So it's the Watts I'm not using that gives me the sound quality?"

"Exactly."

For the next ten minutes, I watched his eyes glaze over as I gave the boy an education.

[Nakatomi]

Try telling that to the absolute 'tard in Currys a few years ago when I went there to buy a new surround sound system for my living room.

"1,000 Watts of sound - that means the quality is amazing!"

"You measure sound quality in Watts?"

"Well, obviously you won't use all 1,000 in your living room. You'll only use about half of that, and it's the extra headroom that gives you the best sound quality."

"So it's the Watts I'm not using that gives me the sound quality?"

"Exactly."

For the next ten minutes, I watched his eyes glaze over as I gave the boy an education.

Haha.
My favourite one used to be 'in digital quality". What, you mean it's aliased, pixellated crap?

I try to avoid those sheds of ignorami whenever possible. I can't stand idly by when customers are being lied to so badly.

[Imagine]

Haha.
My favourite one used to be 'in digital quality". What, you mean it's aliased, pixellated crap?

I try to avoid those sheds of ignorami whenever possible. I can't stand idly by when customers are being lied to so badly.

What????

You mean all of those gold plated HDMI leads I was sold by a chap in the pub are no better than standard ones? :o :bang:

[Marc J]

Try telling that to the absolute 'tard in Currys a few years ago when I went there to buy a new surround sound system for my living room.

"1,000 Watts of sound - that means the quality is amazing!"

"You measure sound quality in Watts?"

"Well, obviously you won't use all 1,000 in your living room. You'll only use about half of that, and it's the extra headroom that gives you the best sound quality."

"So it's the Watts I'm not using that gives me the sound quality?"

"Exactly."

For the next ten minutes, I watched his eyes glaze over as I gave the boy an education.

Reminds me of a conversation I had in John Lewis to the Sonos rep there just a few weeks ago. In trying to get my overall lag down in online gaming (on my PS4), I'm replacing things one by one to get rid of internet lag, display lag and controller lag. Which so far has meant replacing my Virgin Media supplied router with a proper one, and replacing my very old TV with a new one (reducing display lag from about 75ms to 12ms).

Anyway, I was looking at the Sonos Playbase or Playbar and wondering how much sound delay the whole Sonos thing introduces. For Sonos to do it's multiroom thing over it's own mesh network perfectly synced, it has to introduce a delay. When watching TV the workaround is to go into the TV's settings and add a display delay until the picture matches the sound coming from the Sonos kit - most newer TVs will let you do this. I knew this, and so did the Sonos rep, but my question was how much delay it introduced. I was also aware that I would probably have to do without the Sonos sound output when gaming and stick with the TV's, as realistically any amount of delay would be unacceptable.

Anyway, the rep's answer was "probably about half a second".

"Half a second?" I asked, kinda shocked.

"Yes, half a second. You're not going to notice that in gaming, which type of games do you play?"

"First Person Shooters."

"Yep, half a second will be fine. You won't notice that."

"So, why have I just spent £1200 over there to shave 60ms (6 / 100ths of a second) from my setup?"

Half a second! :muppet: I could kill 5 people in that time :D

Anyway, I've since found out through my own research that a Playbar or Playbase introduces around 30ms of display, not half a second. But even that's no good :)

Anyway, sorry for the off-topic post - carry on!

[Nakatomi]

Half a second?! HALF A SECOND?!

Anyway 30ms is actually pretty good for anything that streams, especially if they're compressing it.

Gotta love sales guys dontcha?

[djdj]

I have a pair of Yamaha wooden 12 inch Speakers DSR12 and a Pair of Plastic DXR15's
I would be happy to put my 12's up against any other system, The sound quality is amazing, and they are plenty loud enough for most of the work I do. In the four years or so that I have had them I have NEVER been asked to turn them up! and regularly have comments on how good they sound.

Skytec do a 1000w Speaker would I buy one NO, But if my Yamahas ever give up the ghost I would be happy to spend the Money to buy some more!

We can get obsessed with power output etc but at the end of the day the ONLY way to rate a speaker is to Hear it. :)

[Excalibur]

We can get obsessed with power output etc but at the end of the day the ONLY way to rate a speaker is to Hear it. :)

And I've got some ugly plastic 15" Proels. They've got a woefully poor power rating. Previous owner said he'd never turned them up more than halfway.
That's because they're :Censored: loud.

[Nakatomi]

I'm just fascinated by the disparity in what manufacturers claim & the reality. If the dsr115 really is only shoving out 100wrms & is as loud & nice as all that (by which I mean it's not struggling & sounds clean still) isn't it all the more amazing? I think it is.

[ckpr2]

Numerous ways of stating power is one problem. PMP. RMS etc
You could scope output of amp to get max volts out then work out that into rated speakers.
Even then if they have skimped on power supply the output could be poorer than expected.