VintageKustom.com: Comment Board » Impedence of JBL D140F

Re: Impedence of JBL D140F [message #27495 is a reply to message #27491]

Tue, 10 September 2019 06:06

stevem
Messages: 4733
Registered: June 2004
Location: NY

Senior Member

Yes that a 8 ohm JBL bass driver if it was original to the Kustom K100 amp.

Being a bass driver it only goes up to 2500 HZ in frequency responce so it's going to sound pretty dark if played thru by a 6 string guitar!

If your plan is to use the JBL on the Vox amps 16 ohm output tap then you will drop off 1/3rd of the Vox amps output wattage due to the impeadance mismatch ,and if the Vox amp was for example a 2-12" model then you also will loose 19% of the cone area which will further make for a sound pressure reduction!

The impeadance mismatch will also roll off some of the Vox amps bottom end.

JBL drivers where wired for reverse polarity , so keep that in mind and prove that out by testing it with a 9 volt Battery,

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