running 2 of the same amps into 1 pair of speakers [ first watt J2's]

The con is that you are only using half the amp and half the power. If your speakers can be bi-amped, you can do the same thing and be using the whole amp/amps, you’ll have a setup that will have twice the power (3db) and using all channels.

@russ69

+1

You get a little bit stiffer power supply, but you are probably better bridging the two sides of the amplifier together, assuming your load impedance is high enough.

Since I believe this is a kit, you'd probably be better off increasing the power supply filter caps overall. 

Iam confused about what you’re trying to do. Are you speakers biampable?

Crøss Talk benefits are the main issue. Maybe some more info on what you’re exactly doing and what types of speakers and amplifiers are you using.

I’m trying to figure out which crossover/ frequency device can best be used for biamping where a tube mono feeds Tweeter and mid and a solid state mono feeds occurredthe bass. This is not easy as there isn’t much in the market available for this sort of thing

I’m trying to figure out which crossover/ frequency device can best be used for biamping where a tube mono feeds Tweeter...

The DBX crossovers work well. 

To the OP......If your speakers are bi-wirable / bi-amp able ( have 4 connectors on the back, 2 for bottom end and 2 for mid/top end ), 2 identical amps, as the pair of Js, would be best off to passively, vertically bi-amp. One amp per speaker. One channel for bottom end and the other channel for top end. This would not work out if the 2 amps were different. Horizontal bi-amping, one amp for bottom end, one amp for mid/top end, might work. But this is tricky with differences of impedance and gain between both amps. Lots of reading material available on the web about these subjects. My best, MrD.

@mfm22,

What speakers do you have?

Mike