3.7 vs. 3.7i

[cma29]

Originally Posted by drchaos

This is consistent with something I saw about the 3.7i change (I can't find the source, sorry), that it involved changing the tensioning in the bass/mid panel during manufacturing.

The tensioning is pretty important and a big Magnepan trade secret---the tension isn't even uniform around the sides, presumably tighter at top and looser near the bottom. Remember the Apogee trapezoid? Why a trapezoid? For the same reason--- a non-uniform geometry makes less resonance degeneracy (multiple geometrical resonances piling up on the same frequency) and so a broader, lower Q, resonance behavior.

The tensioning (and the resonance dots) are part of the 'black arts'.

Perhaps the bass on 3.7 non-i was a bit overdamped vs the ideal and the 3.7i change fixes this. It corresponds to the description of something that was adapted into the manufacturing process at low cost, unlike the major model upgrades.

The description of the phase-coherent crossover I think refers to changes from 3.7 over 3.6.

drchaos - welcome and please keep posting!

[magnut]

Apologies for breaking the rules. Should have known better.

[Sceptic]

Originally Posted by drchaos

This is consistent with something I saw about the 3.7i change (I can't find the source, sorry), that it involved changing the tensioning in the bass/mid panel during manufacturing.

The tensioning is pretty important and a big Magnepan trade secret---the tension isn't even uniform around the sides, presumably tighter at top and looser near the bottom. Remember the Apogee trapezoid? Why a trapezoid? For the same reason--- a non-uniform geometry makes less resonance degeneracy (multiple geometrical resonances piling up on the same frequency) and so a broader, lower Q, resonance behavior.

The tensioning (and the resonance dots) are part of the 'black arts'.

Perhaps the bass on 3.7 non-i was a bit overdamped vs the ideal and the 3.7i change fixes this. It corresponds to the description of something that was adapted into the manufacturing process at low cost, unlike the major model upgrades.

The description of the phase-coherent crossover I think refers to changes from 3.7 over 3.6.

From a person who has made the i-upgrade "Shelia said no burn in for the upgrade.....and they did not touch the Mylar, but my socks and side rails were off..."

Could also be the damping tape behind the midrange.
First Listen: Magnepan 3.7i loudspeaker | Hi-Fi+

[Sceptic]

Originally Posted by audiot servant

Hi Mike,

I had the opportunity to compare the 3.7 and 3.7i for an arvo at a mate's place in a system much like my own so was easy to spot the differences. He also has Mye stands so we could compare those and the Sound Anchors.

The changes between the original 3.7 and upgraded panels and the change with adding stands was essentially different in nature.

The change from 3.7 to 3.7i we agreed was primarily a balance shift with additional fullness in the mid bass to lower mids which made for a slightly richer sound overall and moved the weight a bit more towards the overall 20.7 balance.

The addition of stands for the 3.7 didn't so much shift the tonal balance in the mid bass to mid range but rather made resolution/focus/clarity/agility gains overall and also some additional extension down lower. The stands also make possible the use of isolation footers which can take you further down the resolution and speed route.

Both benefits seem valuable so possibly it comes down to whether you feel like you need a richer presentation (3.7i) or a faster more resolved one (stands and mechanical isolation) while keeping the balance fairly largely similar with more extension down lower tho if your running subs this might be less an issue.

Graham

Hi Graham, I have some additional questions regarding the difference between the 3.7 and 3.7i, any chance you could contact me?
Regards,
Hasse
mettef@telia.com

[Jbauza]

Audition the 3.7i yesterday and was not too impressed to spend the money for the upgrade and shipping. I am currently very satisfied with my 3.7 and an old subwoofer. I think that once I upgrade the subwoofer it will be perfect.

[audio bill]

Jbauza, glad that you had the opportunity to audition the newer version to make up your own mind. Many others are just trying to rationalize their decision whether to upgrade or not based upon what they have read or the lack of details provided about the upgrade.

[vidiot33]

I had 3.7's and sold them. From all I could determine, the 3.7'is are only a marginal, incremental improvement over the original. Whether they're worth the premium, is up to the individual. The guy that bought mine had them shipped to Magnepan for the update, but he got 1 year old 3.7's for $2500.

[mgard]

Originally Posted by vidiot33

I had 3.7's and sold them. From all I could determine, the 3.7'is are only a marginal, incremental improvement over the original. Whether they're worth the premium, is up to the individual. The guy that bought mine had them shipped to Magnepan for the update, but he got 1 year old 3.7's for $2500.

Wow, I hope he appreciates the great deal you gave him!


~Mike

[vegaracer1]

Wow,Magnepan really has this upgrade locked down as to what the specific improvements are. If only are national security secrets were this secure.lol