I'm looking for advice on cabin sound insulation in a PA-30 (original model, #114). In threads from a few years back (2013) the suggestion seems to be SoundEx. Has anyone tried the "Super Sound Proof" that Aircraft Spruce sells (also available direct from the manufacturer )? The main reason I'm looking at it is that it's far cheaper - something like $300 total compared to $1700 for the PA-30 SoundEx kit that Aircraft Spruce offers. I gather that this insulation is very similar (possibly identical) to the type that Airtex sells.

My main concern is that the adhesive provided with it is apparently very permanent; once it's stuck down getting to the bare aluminium again (for inspections, mounting/removing antennas, etc) will be difficult. They've suggested getting the non-adhesive version and some weaker glue to hold it down in areas that are likely to require access in the future.

Has anyone here got further suggestions? If SoundEx is really the best thing then that's what I'll get, but if I can save a lot of money with the alternative then that leaves more money for other things.

Thanks in advance,
Evan

I haven't thought much about weight simply because I haven't found any useful figures yet. None of the products I've looked at list a mass/density, nor do they specify exactly how much material is used. SoundEx seems to use a range of thicknesses (0.5" to 1") whereas the Super Sound Proof manufacturer recommends to use 0.5" all over - but this doesn't mean much if the density is significantly different.

Given the price, I'm inclined to get the Super Sound Proof stuff and see what happens - if it's too heavy or not effective enough then at least it'd not too much money wasted.

Airtex knows the planes. I talked to Mark
Kasper at Airtex. He sent exactly the right
Amount of insulation. There interior kit
Was easy to install too. About $400.00