800w v 500w - difference?

[lownote]

Wonder if someone has a steer for me on how much more oomphy is an RM800 head than say a MB LM3? Is it 60% more noisy, or one of these things where the difference in real life is tiny?

[paul_c2]

The difference is 300W. Sorry, someone was going to say it, I had to be the first.

[lownote]

watt?

 

[Jakester]

6 minutes ago, lownote said:

Wonder if someone has a steer for me on how much more oomphy is an RM800 head than say a MB LM3? Is it 60% more noisy, or one of these things where the difference in real life is tiny?

 

In my limited experience, using my CMD121P at 300w is fine - it's loud, but it needs to be turned up and if driven hard can get a little unruly. 

 

Using the extension cab to get the 'full' 500w means it can go as loud without being turned up as much, and getting unruly. All things being equal, it would probably go louder than I would want/need before I experienced any adverse effects through the speakers. 

 

It's not so much it's oomphy, rather that it allows you to go that bit louder, more easily. However, if you were using an 800w amp through the same cab as you used the 300w amp, you might find it gets louder quicker but could also be way too much for the cab, resulting in damage.

[itu]

Let's put it this way:

2 amps - 2 cabs

I'll round those amps to a 400 W and 800 W units (because of numbers, you'll see).

 

We have two cabs. Both can handle the same power, 800 watts. The first is efficient: 95 dB/m/W. The second is less sensitive, 89 dB/m/W.

 

We have now four amp+cab alternatives:

1) 400 W + 89 dB/m/W

2) 800 W + 89 dB/m/W

3) 400 W + 95 dB/m/W

4) 800 W + 95 dB/m/W

 

The sensitivity means, that with 1 watt of power you can get 89 dB or 95 dB from the cab. (I know, the numbers are unfair, and the latter is close to unrealistic.) This also equals, that doubling the power to two watts we get 3 dB more loudness (92 and 98, that is). 

 

1 W - 89 dB

2 W - 92 dB

4 W - 95 dB

8 W - 98 dB

16 W - 101 dB

32 W - 104 dB

64 W - 107 dB

128 W - 110 dB

250 W - 113 dB (rounded a bit)

500 W - 116 dB (amp #1)

1 kW - 119 dB (amp #2)

 

1 W - 95 dB

2 W - 98 dB

4 W - 101 dB

8 W - 104 dB

16 W - 107 dB

32 W - 110 dB

64 W - 113 dB

128 W - 116 dB

250 W - 119 dB

500 W - 122 dB (amp #1)

1 kW - 125 dB (amp #2)

 

In this latter example even the lower power amp reaches the threshold of pain. 

 

If you are still with me, you see from the numbers that loudness is pretty much the same with similar cabs. But if there is difference between the cabinets, the difference in loudness can be substantial with higher power amp and the more sensitive cab against lower power and lower sensitivity.

 

To add something about loudness and ears, 85 dB is the limit, where you can be 8 h / day without protection to avoid hearing loss.

88 dB - 4 h

91 dB - 2 h

94 dB - 1 h

97 dB - 30 min

100 dB - 15 min

103 dB - 7 min 30 s

106 dB - 3 min 45 s

109 dB - 112 s

112 dB - 56 s

115 dB - 28 s

118 dB - 14 s

120 dB - t. of pain

 

How hard you need to push the set, and how long?

What?!

[fleabag]

1 hour ago, lownote said:

Wonder if someone has a steer for me on how much more oomphy is an RM800 head than say a MB LM3? Is it 60% more noisy, or one of these things where the difference in real life is tiny?

 

I doubt you would hear much difference between 500 and 800

[paul_5]

40 minutes ago, fleabag said:

 

I doubt you would hear much difference between 500 and 800

And very little afterwards too. 
 

 

[Downunderwonder]

Depends on the cab(s). Not many individual cabs will do a heck of a lot more with the extra 300w, other than space heat. Plenty of dual cab stacks would be the same story. By the time the tune changes you are going to be absolutely deafening and drowning out all nuances of the drumkit. 

[Baloney Balderdash]

All other things being equal, that is design wise and going through a similar cabinet, an 800W amp will theoretically/technically, and likely in practice too, only be about just bellow +2dB louder than a 500W amp, try turning a booster through an amp with clean head room enough up +2dB and see if that'll really be worth it.

Edited July 30, 2022 by Baloney Balderdash

[Count Bassy]

However if you run your 500w amp at 500watts then using an 800W at 500w will mean that the amp has extra headroom and thermal capacity. ie it's less likely to stop working.

[Downunderwonder]

1 hour ago, Count Bassy said:

However if you run your 500w amp at 500watts then using an 800W at 500w will mean that the amp has extra headroom and thermal capacity. ie it's less likely to stop working.

Yet if you fail to hear the cab complaining about  additional transient peaks coming through you could find you have a silent cab.

[mcnach]

On 28/07/2022 at 18:16, fleabag said:

 

I doubt you would hear much difference between 500 and 800

 

Years ago I got an LMT800 when my main amp was an LMIII. I thought the additional 300W would mean I'd notice it being able to get noticeably louder. It really didn't. It was probably louder, as the different rating would suggest, but I didn't think it was significant enough to warrant switching to an 800W amp just for that. I ended up selling the LMT800 because I liked the sound of the LMIII better.

I used the same speaker cabs with the amplifiers: 1 or 2 Barefaced Big Baby 2.

[Cosmicrain]

In very basic terms, if you want physically twice as loud as 300watts you would need to have 3000 Watts, as it's logarithmic.  So the difference between 500Watts & 800Watts is basically nothing.   However, as an example, a 300watt amp feed into a 1X12" cab with a speaker driver that has a high dB sensitivity rating (say 107dB's) would sound louder that a 500Watt amp feed into a 1X12" cab with a low dB rated sensitivity speaker driver (say 89dB's) assuming both speaker drivers in this example are 8 Ohms each.     The light bulb in my office is 60Watts, but I can't hear  'F all'  coming out of it...just thought I'd throw that one in there.