**Horn Loudspeaker in Car**

**1st January 2004 - report written and
upload**

**True event around April 2003**

**In Car Study**

The system: -

- Alpine Head Unit model CDA-7939E
- Linear Power Pre-amp model PAII
- Precision Power Stereo 1/3 octave 30 band Equalizer model DEQ-230
- two units of Bostwick Active Crossover model EC2i
- two units of Linear Power Amplifier model 452i
- Signat Power Amplifier model RAM-4
- Image Dynamic Horn
- Bostwick 654 Mid Bass 6.5"
- Bostwick 1568 Woofer 15" double magnet

- The woofer will be band-passed from 27Hz to 100Hz
- The mid-bass will be band-passed from 100Hz to 480Hz
- The horn will be high-passed at 480Hz

Signat Power Amplifier model RAM-4 is a 150 watts RMS per channel stereo amplifier. It has two 30 amps fuses which is capable of consuming a minimum of 12v times 60 amps = 720 watts peak. At RMS which is 720 times 0.707 = 509.04 watts RMS. Further coupled to the assumption that power amplifiers are 50% efficient therefore 509.04 divide by 2 = 254.52 watts RMS bridged. Well approximate. Just enough to power a single 15". More power is needed to safeguard headroom for high dynamic musics.

Linear Power Amplifier model 452i is a 22.5 watts RMS per channel stereo amplifier. It has two 5 amps fuses, which when using the above assumption gives 42.42 watts RMS per channel. Just enough for the mid-bass. Again more power is needed.

hhehehehehe, Linear Power...............under spec???.................value for money...........

Finally another Linear Power Amplifier model 452i to power the horns. This will be more than enough.

Signal Path: -

- Horn Loudspeaker in Car
- Smoothed
- Left Only
- EQ Attempt 1
- EQ Attempt 2
- Fullrange Study
- Horn Flip Phase

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