Pioneer PD-200S on Horn No.1603 (ES-800 Biradial)
In this blog post I feature a recent build for a customer who commissioned me to build a Biradial horn for his vintage Pioneer PD-200S compression drivers.
- Circa.1974 (almost 50 years old)
- Highest class series for Pioneer at the time
- Pioneer referred to it as the “Super Sound Series”
- 34mm Diameter External Thread (1.5mm pitch)
- 19mm Throat Diameter
Horn No.1603 Features
- 800Hz Fc
- Cherry hardwood
- Throat adapter (19mm to 25.4mm)
- Driver cradle
- Side mounted Autoformer with NL4 connector
- Rubber feet
Impedance Sweep (see below)
- FS at 480Hz.
- 16ohm at 3kHz.
- Resonance at 1100Hz which we can see in future graphs.
- Diaphragm breakup occurs starting at 11kHz.
Shown below, we see the resonant peak coming in at 1100Hz. This is followed by a -4dB drop at 2.5kHz. The response then slowly and gently rises to 11kHz where is falls off sharply at the diaphragm breakup mode.
I set the test tone to 90dB SPL at 1 meter and measured the harmonic distortion. 2nd order is -45dB down at 2kHz along with 3rd at -56dB, and 4th at -70dB. The distortion profile across the frequency spectrum is relatively consistent.
Environmental Noise is shown below for Reference. I set the 12 bad per octave multitone test signal to 90dB and monitored the noise spectra generated by the driver. We see IMD products -50dB down at 2kHz increasing to -42dB at 10kHz. Adding a 4kHz 4th order high pass filter sees this figure improve to -60dB at 10kHz.
The customer has indicated that these drivers hold sentimental value. Mounting them to the ES-800 Biradial means musical enjoyment for many more years to come.