I have a highly modded S1 Exige with Honda SC & CC.
External noise is not too high and acceptable on enough tracks that it does not concern me.
However, interior noise levels get tiresome when travelling any distance. (Maybe I’m just getting old 
)
Are there any ways of reducing interior noise, whilst not affecting exterior sound, and also not reducing power? Any suggestions?
Decent set of earplugs. Yes, being serious its makes a huge difference.
Yup plugs or ear defenders, John is right.
My car is a very similar spec. I bought some ear-defenders for my son for taking him in the car. They were in the footwell when I set off for Anglesey so I decided to put them on. What a difference! I never do any distance now without ear defence. Apart from anything else it makes it far less tiring.
LOL, yes, that’s what I’ve been doing so far - earplugs when going far 
I was just hoping for a better solution.
I too first used them the day I collected the car from the Midlands, because I was bringing my son along for the ride
Mine is definitely worse (unsurprisingly) since the bulkhead sound deadening came out, so that does do something.
It’s the charger induction shriek that really is painfully loud,…there is an answer to that of course…
What he said (and he’s a top mech who ought to know if anything actually worked).
Try a cheap pair from B&Q to prove the point. You’ll be surprised how it takes out the tiring noise but leaves a surprising amount of what you want.
What did you replace it with Ben? 
I think the best solution would be to put a ‘K’ series back in it!
I put earphones in, bit of spotify etc
Yes, mine has no soundproofing remaining anywhere.
Looks like its earplugs then
Why bling gold foil of course, well know for it’s sound deadening capabilities
Yes Jas, ear-defence is where it’s at. My son’s blue cheapo ear-defenders do make me look like a twat though…ok more of a twat (before some smart arse chimes in)
Ben wears ear defenders and thinks he’s a twat
Because his car is loud, no doubt the fault of Matt
But when push comes to shove and the chips are down
He still drives the thing like a f-ing clown
Noooooooooooooooooo
Riposte required, Ben!
Bose Quietcomfort 20i buds.
I’ve got sad news guys, 'bout Sean I’m afraid,
It’s not just his mojo that he’s mislaid,
He’s actually lost his bollocks when it comes to driving quick,
Above 60mph he starts to feel sick,
He went to the Doc to see if anything could be done,
But the doc said 100bhp was the most that he should run
So the Audi Exige? Well he had to take it to bits,
Even pootling about in it gave him the shits,
The RS6? Well that too had to go,
He soiled his pants even driving it slow,
So, please be kind if he’s piloting something inferior
He needs something under-powered with a wipe-clean interior
Good reposte Ben. I see exiges is more cultured than most forums
HAHAHAHA. Good one matey.
Brilliant, Ben 
Bens gone all ‘family’ with an age old saloon,
“But its got a V8” we constantly hear him croon,
His spuds can deliver, his swimmers are strong,
His five zillion kids, show that can’t be wrong,
As ‘Benja Utd’ comes up to full strength,
And bad boy Ben keeps exercising his length,
The M5 will descend into sorrow and woe,
Crisps on the carpet, Crayolya…. Oh NO!!
So to his trusty Exige, he will beat a retreat,
His wife won’t get in it to mess with his meat,
He will fire up that Honda, start coming across a bit daft,
While muttering a prayer to the god of the drive shaft,
He’ll pull down the pit lane, out onto the straight,
Accelerating hard, wishing he’d lost some more weight,
Then will it all go wrong when he gets to a turn,
He finds it so hard from an instructor to learn,
He saws at the wheel and moshes the brake,
His life in his hands once again he will take
He spots the apex and puts on more lock
Then spins round and round like a bloody great cock!!!