I'm really after the John Entwistle sound. What I mean is sending the low frequencies into one amp and sending the high frequencies into another amp and then adding the overdrive/distortion to the high end while keeping the low end clean as a whistle.

I don't want to rout out the wood in my bass and attach different ports because that would be too much of a job so are there any devices/pedals/effects boxes/amp heads/etc anywhere that can do what I described?

The only thing I can think of is splitting your signal into 2 amps, one amp with 8in or 10in speakers, that'll be the high end/OD amp, then another with 15 in speakers for the low end. I am not really sure if there is a way to divide the frequencies without altering the bass somehow...There's a lot of info on the internet though, I'm surprised no one has how John accomplished this, though I haven't looked actually...

_________________
RAMA LAMA FA FA FA

You could remove your current monaural jack (input plug) in your bass and replace it with a regular stereo jack. I mean a true stereo jack, NOT the three terminal monaural jacks such as for EMGs which most erroneously call, "stereo". For all outward appearances, this looks and fits just like a regular monaural one and of course, is a direct replacement for the monaural one. One half of the jack would be wired to the neck pickup whereas the other half would be wired to the bridge pickup. (This would also require dismantling the wiring from your pickups to the pickup selector switch.) You will then have two separate circuits inside your bass, one for each pickup. Next, you would use a stereo splitter cable from this jack where the stereo cable splits into two monaural ones. The one cable carrying the neck pickup would go to one amp and the other cable carrying the bridge pickup would go to another amp. And yes, both monaural cables can go to the same amp if for whatever reason, you don't want to use two amps in certain instances.

_________________
You dig?

I'm not all that familiar with frequencies but wouldn't some kind of crossover like used in PAs do the trick?I wasn't involved with the sound system much when I was playing but I know there was something used to send the lows to the bass bins and the mids and highs to other cabs.

_________________
'65 Strat,65 Mustang,65 Jaguar,4 more Strats,3 vintage Vox guitars,5 Vox amps,'69 Bassman with a '68 2-15 Bassman cab,36 guitars total-15asst'd amps total,2 vintage '60s Hammond organs & a myriad of effects-with a few rare vintage ones.

This is how home audio speakers work, at least ones with more than a single driver. There are inductors and capacitors in the speaker that split the signal, lower freguencies to the larger driver and higher freq's to the tweeter.

But, the electrical signal coming out of a guitar jack and one going into a speaker box are going to be very different.

Never seen nor heard of a simple, inexpensive, off the self device to do this.

Try diyaudio.com, this is a forum for electrical engineer, audio hobbiest types.