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Magnepan 1.7s in a 10x13' dedicated room?

I'm planning on upgrading my speakers soon and want to go back to Magnepans. I'm considering MG12s but came across nearly new 1.7s on Craigs List for a good price. Problem is, my room is only 10x13x8', but I can do anything I want to it. It already has three bass traps, (two in front corners, one at ceiling wall juncture in back) and 24 1x2' Auralex absorbers spaced around the room. Floor is hardwood with a big think area rug. Anyone put 1.6s or 1.7s in a room of similar size?
linesource
johnnyb53
3,510 posts
 
Rodman9999, what's your point?
rodman99999
6,206 posts
 
To double the apparent loudness of a system by 2 times(10db) takes 10 times the power. 3db is about a 1.23 times increase in loudness and the increases are not linear, but- logarithmic. (http://www.cs.sfu.ca/~tamaras/digitalAudio/Linear_vs_logarithmic.html) (http://www.cs.sfu.ca/~tamaras/digitalAudio/Decibels.html) 115db, from Maggies with 35WPC? That'll be the day!
johnnyb53
3,510 posts
 
I posted "From there, you double the power required to raise loudness in increments of 3dB."

I was adhering to the "double the power for a 3dB increment" principle all along. Start with factory spec 86dB at 1W input in an anechoic room; factor in a second speaker (+3dB=89 dB at 1 wattt) and room gain (another 3-6 dB) and you could get 95dB at 1 watt input per speaker as the stereo in-room starting point. From there, 1x2x2x2x2x2=32 watts as the result of five doublings, making for a 5x3=15dB increase. So in a small room you can hit 105 (my intended figure) to 110 dB (depending on room gain) with around 35 watts x 2, making 70 watts.
rodman99999
6,206 posts
 
You still are trying to figure your power requirements on a linear scale. Did you even read the treatise I first mentioned? The first two paragraphs following the chart couldn't state it more clearly. Hopefully, Linesource will understand, and not expect the miracles you've promised.
johnnyb53
3,510 posts
 
06-22-15: Rodman99999You still are trying to figure your power
requirements on a linear scale.
No I'm not, and the 10dB scale and the 3dB scale are not in conflict. It's not
an either/or situation. There are two common ways of looking at amp
power output vs. perceived loudness, and BOTH are logarithmic.

One scale looks at 3dB increases in SPL vs. doubling amp output. That's the
scale I'm using:

1w to produce 95dB
2w to produce 98dB
4w to produce 101dB
8w to produce 104 dB
16w to produce 107dB
32w to produce 110 dB

A doubling of power for a small linear increase IS a logarithmic relationship.

The other scale looks at 10dB increase in SPL (subjective perceived doubling
of loudness) requiring a tenfold output in amplifier power.

In that case, you'd have:
1w to produce 95dB
10w to produce 105dB
100w to produce 115dB.

Galen Carol starts with the 3dB/double the power scale and shifts after two
increments to the 10dB/10x the power ratio, but they're still both
expressions of the same logarithmic relationship between SPLs and the
power required to increase them.

By the 3dB/double the power scale, you need an eightfold increase of power
to see a 9dB increase in SPL. That's not all that different from a tenfold
increase of power to see a 10dB increase.

I'm only claiming a 15dB increase in SPL for a 32-fold increase in power
output. Search the web anywhere; in just about any discussion of amp output vs. speaker output in dB you'll see both relationships given time
after time: double the power for every additional 3dB, or ten times the power
for 10dB additional loudness.
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