I found an new pair of Motorola piezoelectric tweeters gathering dust behind the rest of my "stored, I'll get around to using this stuff eventually" audio junk. I decided to build an old school pair of 1 PI's. I checked the archives, but I need a bit of help. I don't know the port size. I also believe you also added a coil in series on the woofer. Help please. I remember these were a great little speaker.
Wayne Parham Messages: 18783 Registered: January 2001
Illuminati (33rd Degree)
I'll send plans.
The box is the same and the woofer circuit is the same. The tweeter hole cutout is a little different and the tweeter circuit is different. Just cut a hole to fit the tweeter in, basically the same size as the one in the current plans minus the "ears" for the hookup wires. The piezo tweeter is hooked straight across the input terminals and runs "wide open".
Later when you want to upgrade, just swap out the tweeters. Those old models with the piezos are near and dear to my heart, sounding very good for the money. At the time I designed them, there was no soft dome option with sensitivity anywhere close. But now that there is, you can get a much more refined sound. So when you can, spring for the upgrade tweeters.
Wayne Parham Messages: 18783 Registered: January 2001
Illuminati (33rd Degree)
One thing I always liked about the DX25 is the surround. It is wide enough to allow a relatively low cutoff.
Vifa has changed it slightly, part number DX25TG09-04 replacing the older DX25TG05-04. There are differences, but not enough to warrant a crossover change. I think there is more unit-to-unit variance than there is difference between old and new, so essentially I consider them to be the same.
Wayne Parham Messages: 18783 Registered: January 2001
Illuminati (33rd Degree)
I used a Fostex horn tweeter a long time ago and loved it. The only problem was it really needed a high crossover point with a steep slope or it would poof. That really limited my ability to use it in a two-way.
My coils for the Alpha 8a finally showed up. These "little" 1 PI speakers are cranking out some fine sounds. Just for fun, after I corrected the crossover, I brought them into the living room and placed them in a system with a Morrison preamp and Transcendent Sound single ended OTL amp. My wife preferred them to a highly rated speaker & so did I. I'm leaving them in the system and can't wait to mess with the heads of a few audiophile friends.
Thanks again Wayne.