I have noticed a couple of things so far. One is I need a setup cd or tone generator for sure The bass seems to be more controlled than before with the tube amp.I'm using a SS MC-2505 for the bottom end and a tube MC-275 for the horns in the Valencias.

I played the Mark Knopfler/Emmy Lou Harris-All the Roadrunning album and it sure sounds sweet. I don't think there is a night and day difference so the old Altec x-over can't be all that bad for as old as it is.

I used the stock split @ 800 HZ. and haven't fooled around with changing it. I think Altec used 800 for a reason so I don't see a big need to fool around with it.

Reading the Rane owners manual is a hoot. They have a sense of humor. Too bad most of the technical stuff is over my head. My peabrain doesn't absorb electronics well I'll figure it out eventually.

• Rane's Notes

If worse comes to worse I can always put it back the way it was

• DIY Thread

I would be willing to bet "haven't exploited the device as more accurate. MLK's comment about "little difference" can be taken with a grain of salt since he's rather a newbie to active systems. In addition to active crossovers I have a hardware RTA, a software RTA, two measurement mics, a rack mount SPL meter and two hand-held SPL meters. You need to use some reference signal to get the thing in line - it ain't going to happen by ear.

Check out the link below:

• ESP

I'm hoping to figure out the manual and maybe utilize some of the old test gear I was given. I have a couple of frequency generators that I think would work If I can figure out how to hook them up.

I'm in no hurry to go back to the passive x-over. I have more time than money so I'll get a handle on it eventually. I've been told that the Valencia speaker has the drivers in line so time alignment is not an issue. I don't know this for a fact but I do know if I wander off of zero on the time delay the sound goes bad in a hurry

The Altec method for aligning the drivers, as I remember it, is to wire the drivers out-of-phase and play a tone at the crossover frequency (here, as with most Altec speakers, 800 Hz). You then find the fore-and-aft position that yeilds an SPL minima - at that point the drivers are in the proper physical alignment.

I think the alignment must be pretty close because when I add any delay the life goes right out of the sound and it sounds like a high powered transistor radio