If the K2 can do 1 watt into 4 ohms I'd expect it would do 1/2 watt at 8 ohms, not 1/4. The drop in volume from 4 ohm to 8 ohm should be small. Noticeable, but small; assuming of course the efficiency of the two speakers is similar.
If you're seeing a big drop in volume between the two rigs are you sure it isn't the switch? Do you get the same low output with the Icom speaker connected to the K2? If you swap the rigs on the switch does the low output suddenly move to the Icom rig? - Keith - -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Don Wilhelm Sent: Friday, December 02, 2005 10:34 AM To: Bob Wehking; Elecraft@mailman.qth.net Subject: RE: [Elecraft] K2 Audio issue Bob, Your biggest problem is the 8 ohm impedance Icom speaker. Most solid state power amplifiers will deliver more power into a lower impedance load - the K2 audio power output spec is for 1 watt max into a 4 ohm load - when the audio output amplifier tries to work into an 8 ohm load, the power will be reduced substantially - likely only 1/4 watt will be available. The other part of the equation is the Sound Pressure Level (SPL) of the speaker - that varies from one speaker to another. The SPL of the K2 internal speaker is higher than normal (in part as compensation for the relatively low audio power available), and while I do not know the SPL for your Icom speaker, I would wager that it is not as high as the K2 internal speaker, and therefore not as loud for the same driving power. As stated many times by Wayne B., the K2 design criteria was for low receive current consumption and that is one reason that the K2 has limited audio power output. The current consumed by a higher powered audio stage could likely take more current than the rest of the receiver. Those of us who want loud audio in the shack would do well to consider using an external audio amplifier - at least that is the solution for me. 73, Don W3FPR > -----Original Message----- > > I have a K2/100 & an Icom 756Pro. I am trying to use a switch box to > switch a Icom SP-21 8 ohm speaker between rigs. When I have the K2/100 > connected to the SP-21 I have to turn the audio control way up to hear > anything, but when I switch back to the Icom radio its audio output is > OK. Is this due to the fact that the K2/100 has a 4 ohm output & the > Icom has an 8 ohm output? > > Bob > WB8DDI > K2/100 # 4998 > _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
