Box Stuffing - too much?

[alanbeeb]

I've been building my own standmounts and now they are ready getting mixed results. On pop and rock they are great but on classical orchestral they are a bit dead and flat sounding.

They are a Wilmslow Audio Gemini kit and there is quite a lot of fibrewool inside them... I am wondering if its just too much? The cabinets are about 60% full of fibrewool if I use the amount in the kit instructions. If I take some out, what will the effect on the sound be?

I am wondering if its simply that the drive units need running in for longer...I've had them running on repeat (facing each other, one out of phase to reduce the noise) for about 36 hours and it has made some difference but I would have thought 36 hours was more than enough.

Any advice appreciated, thanks.

 

[RustyB]

Normally a reflex design should have a minimal amount of fill. For a speaker like this I would line the walls with foam and place a block of polyester against the rear wall to absorb the back wave of the woofers. There should be a clear path from the back of the woofers to the port opening.

I would expect an MTM with a pair of small woofers to sound very lively. Have you checked that the tweeters are connected with the correct polarity? If for some reason they were out of phase, you'd get a suckout in the crossover region.

 

[alanbeeb]

I took some of the stuffing out and it seems to have opened out the sound a bit. The wiring is in phase OK. However I think it may have been that I had set my crossover to compensate too much for the difference in sensitivity between woofer and tweeter and so the woofer range was too dominant. Sounds much better since adjusting that.

 

[Iain]

I have removed the fibre wool from a lot of speakers and lined the wools with carpet instead ( preferably not foamed backed). I have found this opens up the mid, increases the bass and is an overall improvement.

Sounds like it would be easy to give it a go!