John Sayers' Recording Studio Design Forum Archive

hello

i've just ordered a pair of fostex fx120s to build thomas barefoot's killatone.

i run a small audio studio and while my main monitoring is likely to keep changing depending on what i can best afford, this 'kilatone' is likely to stay on.

firstly i'd like to know if its absolutely essential to use "non inductive" resistors, as i understand, they are hard to come by, here in india.

secondly, i would really like to make the cabinets out of hardwood, specifically, afromosia, a very heavy and beautiful wood. now, i know that hardwood is not recommended for the purpose, but as i understand, almost any speaker has to make a few compromises based on realistic sensibilities, might i not make this one additional compromise based on my whim? i'm looking for someone to tell me "go ahead, it won't degrade the sonics significantly much", or for somebody to tell me "NO! what it does to your sound is simply not worth the eye candy, the difference is audible everytime".

anybody care to send out an encouragement or warning to this first time DIY enthusiast?

thanks,

self.

The wood should be fine as long as it's dense. If you can't get non-inductive resistors try using putting four 32 Ohm resistors in parallel. This will reduce the inductance by a factor of four. It should be fine. The Killatone has fairly limited high frequency response anyway.

Thomas

Can I use Baltic Birch for the cabinet?
Any predictions as to how it will sound compare to MDF?

" The "crossover" consists of a parallel impedance compensation network (R2, C1) along with a baffle step compensation filter (R1, L1). "

Also is impedance compensation absolutely necessary in this design ?

Thanks

Birch plywood shouldn't make a big difference. Extra internal bracing is always a good idea. Just increase the cabinet dept to compensate for the lost volume.

The impedance compensation flattens the rising inductive impedance of the voice coil. If you remove it, then the baffle step high-shelf filter won't work properly. You could probably reconfigure the baffle step filter somehow; maybe by putting an inductor in series with R1. But this is just trading one type of impedance compensation for another.

Thomas