Tweaking out the Randall iso cab

TwilightOdyssey

Darkness on the edge of Tone
I love my iso cab, I really do. But, as we all know, a boosted 4 or 5W amp is SCREAMING loud in an apartment and 29dB of cut is not all that much in a busy household, let alone one in an average NYC apartment.

There was a Keith Merrow video in which he said a friend of his loaded his Randall iso cab with Auralex foam and it really improved the sound. I thought, why not? And if it cuts off some of the leakage from the cab, even better!

So after hung ga class today, I stopped at the Guitar Center on 14th St and picked up two 2'x4' sheets of Auralex 2" Studio Wedge and a can of Auralex Foamtak adhesive. The adhesive turned out to be unneeded, as the foam fits so tight inside the cabinet that I didn't need to glue it in ($25 wasted).

After making a few measurements, I cut up 5 pieces and lay them inside the cabinet. Of course, acoustically, I noticed a vast change in the cabinet. It went from sounding like a very pingy box to sounding much more substantial. I then cut 5 more pieces, slightly smaller, and affixed them into the first layer.

End result: It cut the leakage down a good 50% I would say.

Playing the Champ with the volume at 9 o clock, you can barely hear the amp with the cab sat right next to you. Boosted, which makes the amp WAY louder, it did sound loud -- but only about as loud as someone watching a movie on the hifi -- not nearly as loud as before.

Placing an SM57 into the cabinet and mic'ing it through my Focusrite mic preamp, I conduced a very quick test and thought it sounded VERY good, indeed.

So, overall, I am very happy and glad I made the plunge. Just gotta find where I put my GRAMMA now ... :)

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Re: Tweaking out the Randall iso cab

The more absorption in the cab the better. It makes the speaker act like it's in a larger enclosure and has the added benefit of more soundproofing.

I have an old Demeter iso cab that has served me well for years.
 
Re: Tweaking out the Randall iso cab

Did this to my randall several years ago. Works great. Roxul works even better.
I have built my own that is four times larger and has at least six inches of rock wool on each side
 
Re: Tweaking out the Randall iso cab

that looks promising! thanks for the recommendation for the gramma pad, I got one for my subwoofer (the smaller version of gramma). I might be wrong, but I think it improved my subwoofer tone and stopped floor vibrations A TINY LITTLE BIT which was worth the price ;)

I would not dare run an iso cab in my small second story apartment though. dont wanna get evicted or have neighbor probs, since neighbors can stop criminals and stuff.
 
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