I searched the diyAudio site for any reference to the 1 inch screw on JBL PTB99HF-1 Waveguide. 6 inches square. 90 x 90 degrees.
I came up empty.
Anyone use it in a project. Listen to it or have anything to say.
I am thinking of possibly applying it as the top end in a bookshelf.
I have a pair plus a pair of JBL 2408H-2 compression drivers to test drive.
I will post some measurements if there is an interest.
Thanks DT
I came up empty.
Anyone use it in a project. Listen to it or have anything to say.
I am thinking of possibly applying it as the top end in a bookshelf.
I have a pair plus a pair of JBL 2408H-2 compression drivers to test drive.
I will post some measurements if there is an interest.
Thanks DT
Last edited:
Hello,
Using the AP tools on my bench I measured the PTBHF99-1, JBL2408H-2. This is what I got for impedance, phase and TS/P. More measurements to follow.
I did not see any wild resonance stuff in the higher frequencies, good news. Sometimes there is breakup that shows up as high frequency resonance.
Note: these are raw data curves. The saw-tooth appearance happens with Compression Drivers and Waveguides/Horns. My suspicion is that some of the output bonces around on the hard surfaces on the longer reflected path out of the waveguide.
Disclaimer:
I am a retired ME. I own more electronic tools than I should. I measure stuff for fun. If I claim to measure or hear stuff, Your Mileage May Vary.
Using the AP tools on my bench I measured the PTBHF99-1, JBL2408H-2. This is what I got for impedance, phase and TS/P. More measurements to follow.
I did not see any wild resonance stuff in the higher frequencies, good news. Sometimes there is breakup that shows up as high frequency resonance.
Note: these are raw data curves. The saw-tooth appearance happens with Compression Drivers and Waveguides/Horns. My suspicion is that some of the output bonces around on the hard surfaces on the longer reflected path out of the waveguide.
Disclaimer:
I am a retired ME. I own more electronic tools than I should. I measure stuff for fun. If I claim to measure or hear stuff, Your Mileage May Vary.
Last edited:
See the attached PTBHF99-1 on JBL2408H-2 plots, typical waveguide/horn roll-off that will require some EQ plus some padding.
If I recall the input voltage was0.5 volts The microphone was ~ 5 inches from the plane of the waveguide flange.
loud output.
low distortion.
Perhaps crossover at 2.5kHz or higher.
Thanks DT
If I recall the input voltage was0.5 volts The microphone was ~ 5 inches from the plane of the waveguide flange.
loud output.
low distortion.
Perhaps crossover at 2.5kHz or higher.
Thanks DT
Attachments
Hello,
A few days ago I bought a pair of JBL AC16 speakers. This speaker uses the waveguide JBL2408H-2. This speaker (AC16) to my ears does not do well with speaking voices speaking in DVD movies. It does better with bass in the movies. Over all too much bass.
Back in the days of Zilch (RIP) there was a Econowave that used the JBL2408H-2.
Thanks DT
A few days ago I bought a pair of JBL AC16 speakers. This speaker uses the waveguide JBL2408H-2. This speaker (AC16) to my ears does not do well with speaking voices speaking in DVD movies. It does better with bass in the movies. Over all too much bass.
Back in the days of Zilch (RIP) there was a Econowave that used the JBL2408H-2.
Thanks DT
After looking at the data sheet, the 2414 is the Compression Driver and the JBL PTB99HF-1 is the screw on waveguide.