Wayne Parham Messages: 18757 Registered: January 2001
Illuminati (33rd Degree)
I'm glad you posted on this thread, because I installed the tweeters, made a few measurements and spent some time listening. Then things got crazy and I forgot to comment about it.
I have moved since then - and am still unpacking and setting up shop so I cannot access my measurement files to post here - but I can tell you that the SB-29 tweeter performs very well as a drop-in replacement for the DX-25. No crossover changes are necessary.
Subjectively, I'd say the SB-29 is maybe a little more "delicate" sounding. By that, what I mean is it sounds detailed without being shrill. It doesn't have any more or less output, and so it isn't a spectral balance thing. But it did sound like it had a little more sparkle to my ears.
It's a very pleasant sounding tweeter. I'm not sure I'd call it an upgrade, though it's definitely not a downgrade either. I'd say it's worth giving it a try, sort of like tube-rolling for the tube-amp guys.
So if I'm reading the data sheets correctly it looks like they are physically different... so if you have already countersunk the baffle for the Vifa then you would have to make some sort of adapter to fit the smaller SB driver?
Just to clarify... there seem to be two versions of this driver
SB29RDC and SB29RDCN
They seem to have different specs. the Neo version is a different physical size and seems to have 1db more sensitivity and a different rising response...
Wayne Parham Messages: 18757 Registered: January 2001
Illuminati (33rd Degree)
About mounting, you're right, the SB-29 mod requires some alteration to fit physically. Not so much if the tweeters are surface mounted but even then, the mounting holes are different.
As to the differences between the RDC and RDNC, I haven't even tried the RDBC. It's quite different actually, both physically and electro-mechanically. We're only talking about the RDC version of the SB-29 here.