New Drivers for BX8a

[Jon Tornblom]

So I have these M-Audio BX8a 'studio monitors' from when I had little experience with good sound. Since then I've realized they sound simply awful; fatiguing and terribly inaccurate. In fact, I don't even want to sell them because I would not want to ruin someone's mixes by letting them use them! haha

Anyway, what I was thinking was that perhaps these speakers could be salvaged by choosing some different drivers. They currently have an 8" woofer and 1.25" tweeter. The main problem is that the woofer is weak in the low mids (esp 250Hz-500Hz), and the tweeter is brash/harsh in the hi mids (esp ~2.5-4kHz). I think they would both have to go.

I mean, they are active speakers with crossovers built in. I understand that more than the drivers might be part of the problem, but I'm not looking for 'main monitors' or anything, just an acceptable sounding set of second reference speakers, or maybe even surrounds.

Here are the specs, hopefully they are useful:

Specifications:
frequency response: 40Hz-24kHz (notice that no +/- db is given here? it's because these would probably measure +/- 8db hahaha)
crossover frequency: 2.2kHz
crossover filter network: 4th-order Linkwitz-Riley
amplifier type: class AB monolithic
low-frequency amplifier power: 70 Watts RMS into 4 ohms (woofer) at 0.5% (-46 dB) THD
high-frequency amplifier power: 60 Watts RMS into 6 ohms (tweeter) at 0.5% (-46 dB) THD
maximum signal-to-noise (dynamic range): > 100dB (typical A-weighted)
polarity: positive signal at + input produce outward LF cone displacement
input impedance: 20k ohms balanced,10k ohms unbalanced
input sensitivity: 85 mV pink noise input produces 90dBA output SPL at one meter with volume control at maximum
power: factory programmed for either 115V ~50/60Hz or 230V ~50/60Hz
protection: RF interference, output current limiting, over temperature, turn-on/off, transient, subsonic filter, external mains fuse
cabinet: vinyl-laminated MDF (enclosure natural Helmholtz resonance frequency: 30 Hz)
size: 12" x 10" x 15"; 30.48cm x 25.4cm x 38.1cm
weight: 26.4 lbs./unit; 11.97 kg.

I haven't really delved into speaker design, so I'm excited to try a small project like this and get into it.

I'm look forward to hearing what your thoughts are. Cheers!!

[Inductor]

Welcome to diyAudio Jon Tornblom,
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