Watts?

[mikel]

Any guys out there have any idea what the ratio is between valve watts and, for want of a better definition, solid state watts?

We now have 1000 watt bass amps, and even greater, when an old 120 watt Orange valve bass head through a 4 x 12 or a 2 x 15 would blow your head off. Our bass player back in the 70s had this setup and never got it above 5 on the master before he drowned out the rest of our 5 piece band. Using 8 of these, about 1000 watts, would have caused an earthquake.

Edited October 17, 2016 by mikel

[chrisanthony1211]

I have a 300 watt Markbass CMD121p and a 25 watt Ampeg B-15 Heritage with a whole load of glowing tubes....and these pretty much throw out the same volume, I know the Ampeg has a bigger speaker, but it still makes a bit of a mockery of the watts equals volume argument, there is so much more to it than merely watts, it's what you do with those pesky watts that counts...!

[markstuk]

I'm sure many other people will chime in - but to sound twice as loud, you need about 10 times the watts... See picture attached..

Watts are Watts are Watts... They're the same whether class A SS, Class D SMPS or Valve.. How fast an amp can deliver a transient and then sustain it is an entirely different matter.

But crudely SS amps sound nasty when you push the power stage into distortion whereas valve amps not so much so..

In my experience my Glockenklang Heart Rock is comfortably louder than my Mesa Four:88. My RH750 is about as loud as my Mesa.. But that's not a true 750W RMS (not even near). All into the same cabs..

All of them are capable of blowing my bandmates off the stage..

Edited October 17, 2016 by markstuk

[mep]

I had one of those Orange rigs with a 4 x12 cab. It was loud. But so was my Trace rig which I believe sits somewhere in between valve and normal solid state watts!

[mikel]

[quote name='markstuk' timestamp='1476734296' post='3156844']
I'm sure many other people will chime in - but to sound twice as loud, you need about 10 times the watts... See picture attached..

[b]Watts are Watts are Watts[/b]... They're the same whether class A SS, Class D SMPS or Valve.. How fast an amp can deliver a transient and then sustain it is an entirely different matter.

But crudely SS amps sound nasty when you push the power stage into distortion whereas valve amps not so much so..

In my experience my Glockenklang Heart Rock is comfortably louder than my Mesa Four:88. My RH750 is about as loud as my Mesa.. But that's not a true 750W RMS (not even near). All into the same cabs..

All of them are capable of blowing my bandmates off the stage..
[/quote]

Possibly, but how did bassists back in the day get away with a couple of 100 watt valve amps and a couple of 4 x 12s, even for the biggest gigs,when no self respecting pro bassist now uses less than a 1000 watt amp?

[markstuk]

1. Big multidriver heavy cabs = many more dB (usually)
2. Amps were driven harder..
3. Bands that want to be loud are louder than they were..
4. I remember having a Hiwatt DR201 with a 1 x 15 cab back in the day and I had to push it very hard to keep up with a 100W marshall with a 412..

[quote name='mikel' timestamp='1476734983' post='3156851']
Possibly, but how did bassists back in the day get away with a couple of 100 watt valve amps and a couple of 4 x 12s, even for the biggest gigs,when no self respecting pro bassist now uses less than a 1000 watt amp?
[/quote]

[Woodinblack]

Purely down to compression. As you start taking a valve non linear you don't really hear the distortion as it is pleasant, so what you do get is a compression of the largest part of the signal. You cant do the same thing with a solid state as it sounds unpleasant, unless you actually compress the signal, in the way the TC RH amplifiers do.

In fact:

http://cdn-downloads.tcelectronic.com/media/914735/tc_electronic_bass_amp_power_rating___active_power_management.pdf

Edited October 17, 2016 by Woodinblack

[mikel]

[quote name='markstuk' timestamp='1476735255' post='3156858']
1. Big multidriver heavy cabs = many more dB (usually)
2. Amps were driven harder..
3. Bands that want to be loud are louder than they were..
4. I remember having a Hiwatt DR201 with a 1 x 15 cab back in the day and I had to push it very hard to keep up with a 100W marshall with a 412..
[/quote]

Still no real answer to my question. Why a 1000 watt solid state amp when an old 100 watt valve amp can make your ears bleed? Why is a 1000 watt solid state not producing twice the DBs of a 100 watt valve?

[gelfin]

Every time you double the watts you get roughly 3db increase (depending on speaker efficiency) Frequency also comes into it. A weighting or C weighting.
So for example ...
100 W makes 100db
200 W makes 103db
400 W makes 106db
800 W makes 109db and so on.

If a 1000w SS amp made twice the db of a 100w valve amp it would be well beyond the threshold of pain.

Its not dissimilar to engine power over speed.

Edited October 17, 2016 by gelfin

[drTStingray]

Back on the 70s, my recollection of bass amplification was it didn't produce a sound anything like recorded sound, and the sound from valve amps started to break up into distortion long before they were running at full power, such that the bass sound disappeared into the mix.

Some bass players, particularly those requiring a cleaner sound at higher volumes (typically an R and B type sound) transferred over to high powered SS amps like Acoustic (John Paul Jones was an example). Leo Lyons was also quoted as saying using an Acoustic stack was not too popular with the rest of the band because of its power (and presumably its ability to stay clean at high volume).

I used to have problems in the 70s competing with loud drummers and guitarists and keeping the bass sound I wanted. My Acoustic 370 on the other hand could drown the band with clean bass sound.

So I don't know the answer to the question raised by the OP but anecdotally modern class D power and lightweight cabinets appear to me to have the ability to offer clean bass sound at high volume without all of the drawbacks of 70s equipment (weight being a big factor).

[Phil Starr]

[quote name='mikel' timestamp='1476736171' post='3156874'] Still no real answer to my question. Why a 1000 watt solid state amp when an old 100 watt valve amp can make your ears bleed? Why is a 1000 watt solid state not producing twice the DBs of a 100 watt valve? [/quote]

I think you've got the answers all here already.

Firstly as a number of people are saying you are comparing a remembered sound with what you are actually hearing today. Old time amps often struggled and when I engineered in the early seventies just getting enough volume was a real struggle. We resorted to lots of speakers and often large horn designs to make the most of every watt. Typically we'd go for speakers with 102dB/watt so you'd get 122dB from your 'typical' 100W bass amp. Few bassists use genuine 1000W amps, in reality 3-500W are more common especially if you stop looking at the advertising and look up the continuous RMS spec in the manuals. Through a modern bass speaker which may only produce 96dB/W that's also 122dB. A lot of modern cabs are also producing a much cleaner sound without so many huge peaks and troughs in the frequency response so they will sound less 'shouty'. I really don't think your 100W valve amp would hold a candle to a 1000W amp through the same speakers.

The second thing is that when you are playing at 100W you aren't actually using all those watts. Lets say your loudest sound is a deafening (literally) 120dB, that first part of the loudest note at the beginning of the bar in your loudest song. Now imagine the quietest sound the audience will hear as you let a note sustain into fade below the hubbub of a gig at the end of the song. That might be 80dB. You've got a dynamic range then of 40dB and your average volume is 100dB. This means your modern speaker needs 4W to make your average sound, well within the capabilities of either the 100W valver or the 1000W ss amp. The rest is your headroom for louder sounds. If you drive the amps to an average power of 10W then you will want the amp to reach 20db higher or 100x the power of 1000W, which your 1000W solid state amp will do but your valve amp won't and neither will the 3-500W class D. The difference is that the 500W amp will distort nastily and sound bad unless you compress the signal. 3dB of compression won't be noticeable for a fraction of a second so you won't notice. The valve amp has a trick up it's sleeve though. It kind of compresses the power peaks naturally and so doesn't distort as much, and because of the way the distortion is structured 10% of valve distortion is acceptable in a way that 10% distortion in a SS amp isn't.

So yes, your 100W amp through an 8x10 is going to match/beat a 400W classD through a 2x10, but swap the speakers round and it'll be entirely outclassed for volume. I'd beat you up a flight of stairs with my stuff though

To answer your question I think subjectively through the same speaker you could probably get a similar volume with acceptable distortion from roughly half the valve watts so your 100W amp might well equal a 200W SS amp. They'd almost certainly sound very different and I admit I'd probably prefer the valve amp if you offered to carry it.

Edited October 17, 2016 by Phil Starr

[markstuk]

[quote name='mikel' timestamp='1476736171' post='3156874']
Still no real answer to my question. Why a 1000 watt solid state amp when an old 100 watt valve amp can make your ears bleed? Why is a 1000 watt solid state not producing twice the DBs of a 100 watt valve?
[/quote]

I think it has been explained (and much better by other bc folk than I did).. cabs are as important (if not more so) than amps...But to answer your original question, the answer is probably somewhere between 2-2.5 times.

Edited October 18, 2016 by markstuk

[xgsjx]

I used to have a Marshall 2x15 rig back in the 90s. It would blow your head off, but it sounded crap in comparison to the Markbass 2x10 combo that I had.

I rememember well the sound of my Markbass. Plenty of volume & easy to keep a clean tone.

I now play through whatever is in the rehearsal rooms. Most often it's a Selmer Treble & Bass through an SWR Goliath. Great sound, but clean at volume it does not do.
Sounds very different from the Class D Markbass. I prefer the sound of my old rig.

Volume is measured in Decibels, not Watts. Watts is one of several factors that determine how many decibels you're gonna get & most of these factors are probably found in the cab.

[Fisheth]

[quote name='markstuk' timestamp='1476734296' post='3156844']
I'm sure many other people will chime in - but to sound twice as loud, you need about 10 times the watts... See picture attached..

Watts are Watts are Watts... They're the same whether class A SS, Class D SMPS or Valve.. How fast an amp can deliver a transient and then sustain it is an entirely different matter.

But crudely SS amps sound nasty when you push the power stage into distortion whereas valve amps not so much so..

In my experience my Glockenklang Heart Rock is comfortably louder than my Mesa Four:88. My RH750 is about as loud as my Mesa.. But that's not a true 750W RMS (not even near). All into the same cabs..


All of them are capable of blowing my bandmates off the stage..
[/quote]

Good post

10/10

Edited October 18, 2016 by Fisheth

[TimR]

Fletcher-Munson.

Modern equipment is as loud at midrange and high fequencies as it ever was, but where it excels is in the low frequencies as you need huge amounts of power to get the bass frequencies to double in volume. An increase of volume in the bass range is a lot less noticeable to the human ear.

Couple this with modern speakers having a much greater XMax (the distance the cone can move) you get a much louder unit for a smaller speaker size.

However the speaker is still what will limit the actual volume. A 100w speaker connected to a 100w valve amp will only produce as much volume as the speaker can handle. Connect it to 1000w and you won't get any more volume out of it as it will physically destroy the cone either mechanically or thermally. (Yes I know. Those particular figures are for demonstration only. )

.

Edited October 18, 2016 by TimR

[ivansc]

One point that is being overlooked is the difference in speaker technology.

I used a 120 watt Orange graphic head back in the day. With a 2x15" cabinet with 2 very efficient Altec Lansing speakers in it.
Nowadays it is a MarkBass LM3 into a 2x10" 4ohm Neo cabinet, which of course means the amp i giving out a max of 500 watts into that 4ohm load.
BUT. The neos are down in the 96dB efficiency range whereas the old Altecs were well over 100db efficiency.
This translates into more air being moved by the Altecs for a given amount of power applied than is possible with the LM3.

So it does mean that far more than just the simple application of "well it four times the power, why aint it four times louder" needs to be taken into consideration.

[Phil Starr]

[font=helvetica, arial, sans-serif][color=#282828]There's another factor in this which we haven't discussed much here. I didn't put it into my over-long last post which was probably already complex enough. Anyway here goes. [/color][/font]

[color=#282828][font=helvetica, arial, sans-serif]TimR mentions 1000W into thermally limited speakers. When you pass 1000W through a 2" voice coil it gets hot, really hot. This increases the resistance in the coil so your 4ohm speaker can become a 16ohm speaker, so the power falls to 250W and the sound level falls. In extreme cases this [b]power compression[/b] can be as much as 6dB. Running a modern ultra powered amp into compact speakers is going to give you more power compression than the old ways of low power into lots of speakers. It may be that running out of oomph (or should that be heft?) halfway through a gig with class D isn't down to lack of watts but too many watts into limited speakers which have over-heated. Google power compression in speakers This is what JBL have to say [/font][/color]

[size=3][color=#000000][font=Verdana, Arial, Helvetica, sans-serif]"Speaker voice coils are made of copper or aluminum. As these voice coils increase in temperature during normal operation, the DC resistance of the voice coil increases. Greater voice coil resistance means less power transfer from the amplifier. As a result, the speaker will not play as loud when it's "warmed up" as it did when it was "cold". Some speakers may exhibit 3 to 6 dB of power compression. This means that power compression can have the same effect as taking away half of your PA!"[/font][/color][/size]

Edited October 19, 2016 by Phil Starr

[mikel]

[quote name='ivansc' timestamp='1476836366' post='3157735']
One point that is being overlooked is the difference in speaker technology.

I used a 120 watt Orange graphic head back in the day. With a 2x15" cabinet with 2 very efficient Altec Lansing speakers in it.
Nowadays it is a MarkBass LM3 into a 2x10" 4ohm Neo cabinet, which of course means the amp i giving out a max of 500 watts into that 4ohm load.
BUT. The neos are down in the 96dB efficiency range whereas the old Altecs were well over 100db efficiency.
This translates into more air being moved by the Altecs for a given amount of power applied than is possible with the LM3.

So it does mean that far more than just the simple application of "well it four times the power, why aint it four times louder" needs to be taken into consideration.
[/quote]

I dont disagree with any of this, but plug your 1000 watt solid state amp into your Altec loaded cab in an AB test with the Orange and what would be the result? Thats what I am trying to discern, is there a marked difference in the watt rating for modern solid state amps compared with valve amps, now or from back in the 70s?

Edited October 19, 2016 by mikel

[Dad3353]

[quote name='mikel' timestamp='1476861754' post='3157778']
I dont disagree with any of this, but plug your 1000 watt solid state amp into your Altec loaded cab in an AB test with the Orange and what would be the result? Thats what I am trying to discern, is there a marked difference in the watt rating for modern solid state amps compared with valve amps, now or from back in the 70s?
[/quote]

Once the SS amp started to deliver the same db level as the Orange, the speakers would start to melt. The audible output would not increase over the Orange, and the full potential power of the ss amp would not be available.
My PA, back in the early '70s, was a 200w Hiwatt DR205. The cabs for that were a pair of these...

Those stacks are over 6 ' tall, and their sheer mass affects the moon's orbit. We used 'em for rock concerts in some quite big venues (2000+..?), and there was no lack of FOH. Only 200w of valves. I don't think any 200w ss amp could even get close to the sound of that rig; I would rather bet on needing at least 1 kw of ss amp. The Hiwatt 200w is, I reckon, rather a conservative estimate, and many ss amps are the opposite.

Edited October 19, 2016 by Dad3353

[leschirons]

I've come to the conclusion that they don't make watts like they used to back in the good old days. When I started in bands in 1968, they were proper watts they were.

[oggiesnr]

Back in the seventies very few bands had large PAs. A lot of touring bands had FOH at around 1000 watts and power amps were expensive. As a club band we had 100 watts FOH for vocals and an overhead mike for the drums, guitars and bass went straight out from our backline which was mainly 100 watt Peavey units.

A lot changed in 1977 with punk and the advent of the HH 1000 watt power amp which was cheap. The Adverts turned up at Hull Uni with the first 3000 watt rig we'd ever had there, The Dammed ran 5000 a few weeks later.

Now I see pub bands pumping out more wattage than used to be used in major halls and at small festivals.

What hasn't changed is the quality of too many "sound" engineers but that's a different issue

[crez5150]

[quote name='leschirons' timestamp='1476863481' post='3157790']
I've come to the conclusion that they don't make watts like they used to back in the good old days. When I started in bands in 1968, they were proper watts they were.
[/quote]

Watt (see what I did there) you find these days, in order to play the 'marketing game', many manufacturers plaster Peak Power or PMP on their advertising as everyone does it... it's become the norm. I work for a manufacturer that produces PA products. Manufacture in the US where a lot of this goes on and in Europe where they are more realistic about true RMS or more importantly SPL of a product.

I'd never purchase a product on the strength of RMS as its pretty useless.... try the product for yourself, get clued up on what the products are actually capable of.

[markstuk]

[quote name='ivansc' timestamp='1476836366' post='3157735']
One point that is being overlooked is the difference in speaker technology.

I used a 120 watt Orange graphic head back in the day. With a 2x15" cabinet with 2 very efficient Altec Lansing speakers in it.
Nowadays it is a MarkBass LM3 into a 2x10" 4ohm Neo cabinet, which of course means the amp i giving out a max of 500 watts into that 4ohm load.
BUT. The neos are down in the 96dB efficiency range whereas the old Altecs were well over 100db efficiency.
This translates into more air being moved by the Altecs for a given amount of power applied than is possible with the LM3.

So it does mean that far more than just the simple application of "well it four times the power, why aint it four times louder" needs to be taken into consideration.
[/quote]

Not true of all Neos - the 3012HO from Eminence will do 100+ dB at 1w/1m..

[mikel]

What I discern, even from the more technically minded on here, is that there is no answer as to why bassists now need 1000 watts when back in the day, when gigs and indeed rehearsals were loud enough to make me temporarily deaf, 100 was fine.. So as one wag just said, watts are obviously not what they used to be.

Edited October 19, 2016 by mikel

[mcnach]

[quote name='mikel' timestamp='1476868940' post='3157864']
What I discern, even from the more technically minded on here, is that there is no answer as to why bassists now need 1000 watts when back in the day, when gigs and indeed rehearsals were loud enough to make me temporarily deaf, 100 was fine.. So as one wag just said, watts are obviously not what they used to be.
[/quote]

I think it was hinted at in a couple of posts as a combination of:

1) An increase of 100 to 1000W is definitely noticeable, but nowhere near as dramatic as the numbers suggest to us mere mortals.

2) We tend to use much smaller rigs these days than then. Fewer speakers in smaller cabs.

3) The speakers may be more able, mechanically, to survive higher power, but not all are more efficient... but because power is relatively cheap you still get a similar effect by pumping more power into them.

Something along those lines.

Personally, as bass player who can't afford a roadie, I am very happy to live in these days