Prof and you other 02 fans - I just now got my old 02s on line - received from my brother from their life-long use in our parents' system. Drivers are good, coils are good - within their genre. These speakers were made in 1978 before we discovered high-purity wire and baked fusing. These are normal ETP "magnet wire", still the industry standard. We wound these on "Ol' George" - hand-fed with a timer. We then tweaked each coil via weight on a triple beam balance and DC resistance. I checked these today with my inductance meter and they're within 2% of target.
They are considerably better wound than Beetle's Chinese 2.4 coils.
Back to the XO. The resistors are 5 watt carbon composition - all burned to a crisp. The caps are all 50 volt electrolytic - about half of them are blown out, the other half are + 30% out of spec. I replaced all with original grade parts and fired them up.
I haven't heard 02s for at least 30 years. I am impressed! The sonic signature / tonal balance is pure Thiel and they don't screw up the music. They lose a little in direct comparison to the PowerPoint1.2s and the CS1.6s, both 6.5" 2-ways, but really, they aren't shamed.
If we had chosen to take this 2nd order route with our developing company, life would have been immensely easier. However, we may have failed because the territory is so much easier - everybody entering the game played there and it is unknown whether we could have differentiated ourselves.
Anyhow, thank you Prof. Your enthusiasm for the model inspired me to consider it. After hearing it, I am addressing it and will learn a lot in this relatively simple sandbox. The 02R will live. I hope you guys can snag some on the cheap. Rob and I think we made fewer than 1000 between 1976 and 1984 and they would be concentrated on the East Coast and in Germany - go figure.
They are considerably better wound than Beetle's Chinese 2.4 coils.
Back to the XO. The resistors are 5 watt carbon composition - all burned to a crisp. The caps are all 50 volt electrolytic - about half of them are blown out, the other half are + 30% out of spec. I replaced all with original grade parts and fired them up.
I haven't heard 02s for at least 30 years. I am impressed! The sonic signature / tonal balance is pure Thiel and they don't screw up the music. They lose a little in direct comparison to the PowerPoint1.2s and the CS1.6s, both 6.5" 2-ways, but really, they aren't shamed.
If we had chosen to take this 2nd order route with our developing company, life would have been immensely easier. However, we may have failed because the territory is so much easier - everybody entering the game played there and it is unknown whether we could have differentiated ourselves.
Anyhow, thank you Prof. Your enthusiasm for the model inspired me to consider it. After hearing it, I am addressing it and will learn a lot in this relatively simple sandbox. The 02R will live. I hope you guys can snag some on the cheap. Rob and I think we made fewer than 1000 between 1976 and 1984 and they would be concentrated on the East Coast and in Germany - go figure.