1.4" vs 2" compression drivers

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Was just looking at some compression drivers both have 3" voice coils both have 2.0 T strength magnets and the same phase plug they are identical except for the throats 1.4" vs 2" are their any advantages to the 2" throat? These will be for home use from 800hz to 8000khz maybe 10000khz in a 3 way system.
 
The horn + CD must be considered as one system, along with your home requirements. So, for 800-8,000Hz....

If you have a large + long horn with a 2" throat, a 4" diameter diaphragm probably has the right power to push the air volume.

If you have a shorter "waveguide" with a 2" throat, a 3" diameter diaphragm (low) compression driver designed with a 2" throat, (AND NOT just a 1.4" compression driver with an expander to 2"), will probably sound smoothest from 800-8,000Hz - 10,000Hz.
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There are 2" exit compression drivers with 4" diaphragms which have a modest length phase plug exit path to the horn. The natural 4"-to-2" dome-to-exit compression ratio is high. The design is optimized for the 700-800Hz up to 8,000Hz with a LARGE ~300-350Hz horn design. EXAMPLE: JMLC-350 horn with 24" diameter mouth. Many designers consider the 4" diaphragm the best tech for 700-8KHz range.

There are 2" exit compression drivers with 3" diaphragms with a short phase plug exit path to the throat. A modest compression ratio. The datasheets show bumpy and reduced SPL 700-800Hz output in large horn, but smooth SPL with short waveguides to 10kHz.

There are 2" exit compression drivers with 3" diaprhagms which start as 1.4" exit and use a short machined metal throat expander attached near the 3" diaphragm to maintain a high compression ratio and improve the shape of the wavefront at the 2" exit. Some designers consider this a 1.4" design with a short 2" exit adapter.

PLASTIC: A few 1.4" exit, 3" diaphragm compression drives with plastic diaphragms and suspensions are used for the 800-15Khz range. A plastic diaphragm does not generate noticable break-up in the 15Khz-18Khz as is common in Titanium. Using a 1.4" exit CD at 800Hz requires a 18"-24" waveguide(short horn like Tractrix)...not a monster horn with high air mass.

With a good waveguide, the Faital HF108 1" exit compression driver which has a 1.75" diameter plastic diaphragm can be used from 900-18Khz. Not a bad start for a home horn speaker.
 

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