JBL E 120 in Peavey L.A. 400

Curt Langston · Post by **Curt Langston** » 23 Sep 2005 7:20 pm

I recently aquired a Peavey L.A. 400 for next to nothing. It is in excellent shape, but someone took the 1203-4 BW out of it. It has a fuzzy sounding(blown) Pyle Driver speaker in it. I got a NOS JBL E-120 (8 ohm) to put in it. I know the L.A. 400 is rated 210 watts @4 ohms. What can I expect with the E-120, with it being 8 ohms. I can't hardly believe that it will cut my power in half. I used a JBL D 130-8 in an old Session 400 one time, and I could not tell the difference in power. Could this be due to the JBL being more efficent?
Any thoughts on this will be appreciated.

Jack Stoner · Post by **Jack Stoner** » 24 Sep 2005 2:03 am

Power will be almost half with an 8 ohm speaker connected to an amp that is rated for a 4 ohm speaker.

The formula for power is P-E2/R. Thus an amp that is rated 210 watts with 4 ohms and has a voltage (max) of 28 volts would produce 98 watts (28X28/8)

Most Peavey's have the voltage rating printed on the rear of the amp.

Another example is the Evans SE-200 amps. They are rated 200 watts with a 4 ohm speaker but the ones that came with the Emminence Delta Lite (neodymium) speaker, which is 8 ohms only have 128 watts output. The only way to get the SE-200's rated output is to use a 4 ohm speaker or have two 8 ohm speakers connected in parallel (4 ohms). (The Evans output voltage is 32 V, 32X32/8 equals 128).

Curt Langston · Post by **Curt Langston** » 24 Sep 2005 5:38 am

Hey thanks for the info. Jack. Much appreciated!