My active XO test rig

[Fuling]

I built this little evaluation platform in order to determine the best crossover frequency and slope for my biamped speakers (FE167E and SS8545 in ported boxes)
The power amps are some cheap TDA2005 kits that delivers a few watts per channel, quite nough for the purpose and they don´t sound too bad either (suprise!)
The active crossover is based on NE5532 buffers and is currently setup for 90hz 12dB/oct but there are empty sockets for extra opamps and filter sections (the RC-sections are soldered to component adapters that fits into DIL sockets).

I know it looks like a mess, but I´m happy with the performance so what the heck...

[Fuling]

And a little closeup on the filter:

[latala]

Nice one
For me this is what it is all about
a journey into the world of electronics!
and remember even the greatest journey has to start with the first step
regards Trev

[Fuling]

I have a bunch of much better amps around the house, for example a 6B4G DRD and a pair of screen driven PL519 monoblocks but I got tired of moving around 50+ kilos of tube electronics everytime I wanted to try something new involving the active XO.
I figured that it would be much easier to build this platform that has four identical power amp channels available, if I were to use my tube amps the different gain and DF figures would make things much less predictable.

Once I´ve determined what crossover configuration that suits my speakers I´ll build a final version with four small class A amps and a filter based on discrete Jfet buffers.

After all this was a quite funny project without high-end ambitions and still it sounds really good!
After hearing this it´s even a little hard to justify the costs involved in building high end tube amps...