Awesome Tone at Lower Volume

[BoogieBoek]

Love the Mark V 90 I have. I absolutely love all of the sounds on 90W and cranking the volume but I'd be deaf quickly running through a 4 x 12 cabinet. If I go with a 2 x 12 or 1 x 12 will that provide the same high gain tone at lower volume? If there are any other suggestions for getting that same tone at lower volume I'd love your suggestions.

 

[Janglin_Jack]

If I remember right, as you double the speakers you get a +3db increase. So if you go from 4x12 down to 1x12 that is halving x2 which should be 6db decrease. I think our hearing is 10-12db increase is perceived as twice as loud. So there would be a significant decrease in volume by reducing the number of speakers. You can also look at a less efficient speaker, but I would say the best way to leave the amp alone and reduce the volume is with an attenuator. Keeps all the same settings and then just turn down the output at the speakers. Classic way to reduce volume but there is cost and concerns with how it affects tone, etc. Generally a reduction is volume changes the tone, weather it is fewer speakers or an attenuator, etc.

 

[sloanthebone]

I am using a Fryette PS-2 and KHE ACS 4x4 switcher for my 4 amps through a Mesa 2x12 vertical cab and it sounds fantastic. I am picking up a Mark V and matching Mesa 2x12 vertical cab tomorrow and will compare that going through just the cab and then through the PS-2/KHE to see if there are any tone changes but I love my JP-2C and Mark IIb through the PS2. They Sound much better to me. The TC50 and Badlander I didn’t think sounded that much different being attenuated because they sound so good without it.

I also had a Mark V and TC50 6 years ago before selling them both and used them through 2 Mesa 1x12s and never really like the tone. I am much happier through the Mesa 2x12 vertical cab.

 

[mace]

I’m pretty sure doubling the amp output wattage increases sound pressure by 3 dB (not just adding speakers). So, any 8 Ohm cab, regardless of 1, 2 or 4 speakers will put out the same sound volume for the same amp setting.

And I’ve also read that perceived ‘twice as loud’ is about 10 dB (three doublings of output wattage).

So, to answer the original question, going from 4x12 to 2x12 to 1x12 won’t really change volume. It will effect tone because at a given output level the speaker of the 1x12 will be working harder than a speaker in the 4x12 (load shared among all 4 speakers).

 

[Janglin_Jack]

Doubling the power is one way to gain +3db. The other is doubling the speakers:

 

[woodbutcher65]

All else being equal, doubling the number of speakers will increase the acoustic output by 3 dB.

So you can knock off 6 dB by going down from a 4x12 to a 1x12.

 

[Janglin_Jack]

Yes, that is the way I see it.

 

[John Micka]

you can also get some resistive powersoak device to install before speaker on output so you can crank the amp and suffer a little on tone, however with adjustments you can dial a pretty good tone. Your 90watt amp will need a 100watt resistive device.
I use a stereo 50/50 set on low and a stereo resistive device for a few years now. Make all around adjustments in my GT1000 and am very happy with the tone when I play these small clubs.

 

[mace]

hmmm…

And what if you have 1024 speakers in a big *** 8 ohm cab. If just doubling speakers added 3 dB then this is 10 doublings or 30 dB louder. How could a 25 amp go from 100 dB to 130 dB just by adding speakers??

sorry for the rambling…maybe I’m off base here. In the video the ‘intensity’ concept is something I’ll admit I’m not familiar with. I am familiar with P=I^2R and that doubling power adds 3 dB of sound pressure. If that video is true for guitar amps (one channel of power) then you could make an amp infinitely loud just by adding speakers, which doesn’t seem right since the power of an amp is limited.

It seems like that video is talking about a stereo amp, where each speaker is getting the same amount of power fed to it. So, one speaker at 100 W and 2 speakers at 100 W each (100W per channel stereo). Yes, the 200 W stereo is 3 dB louder than 100 W mono.

 

[Markedman]

Using only one speaker will never sound as good as using four speakers, it’s just the way it is, especially at low volume.

 

[martinlb]

hmmm…

And what if you have 1024 speakers in a big *** 8 ohm cab. If just doubling speakers added 3 dB then this is 10 doublings or 30 dB louder. How could a 25 amp go from 100 dB to 130 dB just by adding speakers??

sorry for the rambling…maybe I’m off base here. In the video the ‘intensity’ concept is something I’ll admit I’m not familiar with. I am familiar with P=I^2R and that doubling power adds 3 dB of sound pressure. If that video is true for guitar amps (one channel of power) then you could make an amp infinitely loud just by adding speakers, which doesn’t seem right since the power of an amp is limited.

It seems like that video is talking about a stereo amp, where each speaker is getting the same amount of power fed to it. So, one speaker at 100 W and 2 speakers at 100 W each (100W per channel stereo). Yes, the 200 W stereo is 3 dB louder than 100 W mono.

I might be, and probably am, missing the point but the first thing that came to mind for me was perpetual motion and more or less how energy works. Adding a 50w speaker, for example, to replace a speaker rated at lower wattage isn't going to result in a louder sound in any way I can imagine. That rating is of course provided to give an idea of how many watts a speaker can handle, not how loud the speaker will be.

I'm probably misunderstanding something though. This isn't an area of expertise for me. Or I'm misreading things.

 

[user 41014]

Using only one speaker will never sound as good as using four speakers, it’s just the way it is, especially at low volume.

Aside from physics and theory this is a limiting reality. Dimension (directivity/dispersion/room air movement) and musicality is what gets limited with one speaker unless you are using a thiele(s). A 19" single cab is the worst thing you can do for your sound.

Find drivers you like in the lower 90's sensitivity if your current ones are high 90's and you will accomplish what you are trying for. I'd make sure you can't dial the front knobs better first.

I haven't yet grabbed a speaker with 1024 drivers but at 30A that's 30mA per driver and there has to be a power minimum limitation.

 

[mace]

100% agree that a 4x12 cab sounds bigger and fuller than a 1x12 cab.

And yeah, speaker ratings in watt are just max power capability.

One thing about speakers is efficiency in converting the electrical energy to acoustical energy. This varies a bunch from speaker to speaker. For example, the big Klipschorn speakers are really efficient and can produce 104 dB at 1 meter distance when fed just 1 Watt. Most home stereo speakers are around 85 to 95 dB-W-m of efficiency. I have no clues about amp cabs and their efficiencies but one type of cab could have more dB per input W compared to others.

I dunno, maybe this efficiency thing is related to when that video was talking about with intensity? Maybe a 4x12 cab is more efficient per input Watt?

 

[woodbutcher65]

The notion that more drivers means more output is based on the simple fact that you're using the same power to move more air by moving more cone surface area. If you had a 1024 driver cabinet, never mind the logistical and structural concerns, then yes it would be 3 db louder than a 512 driver cabinet, 6 db louder than a 256 driver cabinet, 9 db louder than a 128 db cabinet, 12 db louder than a 128 db cabinet, 15/64, 18/32, 21/16, 24/8, and yes, 27 dB louder than a 4 driver cabinet. And 33 db louder than a single driver.

It's not free power, it's just making more efficient use of the available power.

 

[mace]

Anyone know what the theoretical max dB-m is for 1 W of power? In other words, what is 100% efficiency with no losses to heat, friction etc?

It seems counterintuitive that a 1 W amp could be made infinitely loud by adding an infinite number of speakers.

Moving air is a volume thing. So, while two speakers have twice the surface area of one, they wouldn't be driven as hard and would move less (maybe half as much as a single speaker). So, the volume of air moved may be the same for a given watt of power. Not sure other than I'm pretty sure dB and sound pressure is a volumetric air thing (not just surface area of driver).

Wonder if anyone at Mesa is on these boards could chip in. LOL they've probably measured this stuff. I guess I could get out the old dB meter and compare 1x12 to 2x12 to two 2x12s (off the 4 ohm taps).

 

[user 41014]

Power is not free. Air movement in a bedroom is not the same as air movement at the back of the Fillmore.

Yes, they are electro-magnetic-mechanical transducers and efficiency varies. If I wanted to run the same cab at lower volume the easiest way to me is 6db lower sensitivity.

In a make believe world a 4x12 speaker with 200 db sensitivity drivers would be enough to run live at Pompeii. In the real world you need more power. Alas power can corrupt. Ha!

 

[Nandrewjackson]

A resistive load and a speaker at the same time can get the power amp into it's sweet spot without needing ear plugs.

A 4X12 with low efficiency (low sensitivity) speakers is a good idea too.

It can seem counterintuitive about more speakers equals louder, but it has a limit. A thousand twelve inch speakers each putting out a tenth of a watt from a 100 watt head might only be a slight fraction louder than a 4X12, or that example might already be past the limit, either way it's ridiculous.

 

[mace]

1024x12. Just a thought experiment. And something for the next KISS tour.

 

[mace]

OK, I did a bit of googling and found this crazy long thread on the Gear Page. The last page has a good video which I think sums up the situation pretty well. I found it hilarious that they upped the 1024x12 cab example to 5000x12 to 10,000x12.

It seems if you want to get better sound at lower volumes then a big cabinet (boosted low end frequencies (coupling), which the human ear doesn’t perceive as well at low volumes) with less efficient speakers may help? Or, a good power attenuator and EQ would work. Anyway, a complex subject, it seems!

https://www.thegearpage.net/board/index.php?threads/more-speakers-more-volume.703405/page-14

 

[Eevil]

OK, I did a bit of googling and found this crazy long thread on the Gear Page. The last page has a good video which I think sums up the situation pretty well. I found it hilarious that they upped the 1024x12 cab example to 5000x12 to 10,000x12.

It seems if you want to get better sound at lower volumes then a big cabinet (boosted low end frequencies (coupling), which the human ear doesn’t perceive as well at low volumes) with less efficient speakers may help? Or, a good power attenuator and EQ would work. Anyway, a complex subject, it seems!

https://www.thegearpage.net/board/index.php?threads/more-speakers-more-volume.703405/page-14

One should separate the psychological perception of loudness from physical pressure waves in medium: Equal-loudness contour - Wikipedia

Better tone in lower SPL will always be personal preference (the better tone -part)

I’ve been thru couple of different attenuators and currently I’m using Captor X to make it possible to get my ED to home practice levels - or straight to headphones.

Tested some less sensitive speakers also but those did not have the V30 tone - so off they went.

Just experiment which approach you like best and then you’ll know