Here are the T/S:
sd - Piston Area 0,0881 Sq M
Revc - DV Voice Coil Resistance 7 Ohm
Levc - Voice Coil Inductance 1kHz (mH) 1,6
BL - Flux Density (TM) 19,5
Vas - Equivalent Acoustic Volume (Liter) 304 liter
Cms - Mechanical Suspension Compliance (x 10-4 m/N) 2761
Mms - Mechanical Mass of Cone and Free Air Load 117 g
Mmd 86 g
Fs - Free Air Resonance Frequency 28 Hz
Qms - Mechanical Q Factor 6,8
Qes - Electrical Q Factor 0,36
Qts - Total Q factor 0,34
Xmax - Max Linear Peak Excursion (O-P) 8,0 mm
Pmax - RMS Thermal power Limit 500 Watt
no - Relative Efficiency 1,81 %
Vd (cm²) 405
Max. Excursion Before Damage (P-P) 36,0 mm
mats
sd - Piston Area 0,0881 Sq M
Revc - DV Voice Coil Resistance 7 Ohm
Levc - Voice Coil Inductance 1kHz (mH) 1,6
BL - Flux Density (TM) 19,5
Vas - Equivalent Acoustic Volume (Liter) 304 liter
Cms - Mechanical Suspension Compliance (x 10-4 m/N) 2761
Mms - Mechanical Mass of Cone and Free Air Load 117 g
Mmd 86 g
Fs - Free Air Resonance Frequency 28 Hz
Qms - Mechanical Q Factor 6,8
Qes - Electrical Q Factor 0,36
Qts - Total Q factor 0,34
Xmax - Max Linear Peak Excursion (O-P) 8,0 mm
Pmax - RMS Thermal power Limit 500 Watt
no - Relative Efficiency 1,81 %
Vd (cm²) 405
Max. Excursion Before Damage (P-P) 36,0 mm
mats
sumsound said:
Here is some information on the Onken and how to build it. Based on the Jensen Ultraflex, the Onken is named after the Japanese fellow and the company that resurrected the design from the "trash barrel" of history.
Link here to good scan of the Jensen plans: http://www.studiomaudio.info/onken.html
Cyr-Marc Debien has created an Onken calculator spreadsheet into which you can enter TS parameters for Onken box design - there are also some design rules which are explained there. Checked link and the calculator is available here: www.hb001.de/ONKEN_CALC.xls (The original site has been taken down.)
Most box calculators don't work that well with the Onken design, but do predict general trends. Also in practical use the design is most critical about the source impedance used to drive it. Have a good sense of the output Z of the amplifier most likely to be used BEFORE you do the design.
Building mine was quite a project, but well worth the effort. Look for the Onken thread here.
Based on calculator results this driver despite having a suitable qts does not seem to be a good match to the Onken box. Initially I thought it was but I incorrectly entered the port dimensions. Svent area should be no less than 85% of the cone area to meet Onken/Ultraflex design criteria and at these values the port dimensions are far too long. The problem here seems to be the high cone mass, lower would be better.
You could make an Onken look alike, but the ratio of Sd to Svent would not be correct for the Onken design.
You could make an Onken look alike, but the ratio of Sd to Svent would not be correct for the Onken design.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.