impedance issues

[rainsong86]

I'd like to use my stereo 2x12 combo along with an 8 ohm 4x12 extension cab.. the combo itself has 2 50 watt/ 8 ohm speaker outputs which normally connect to each of the 8 ohm speakers built into the combo.. so I need to combine the two 8 ohm speakers of the combo in SERIES so that I can plug them into one of the 8 ohm speaker outputs and have the other speaker output connected to the extension cab.. the former being a safe mismatch (8 ohms into a 16 ohm load) and the latter being a perfect match... each of the combo speakers connect to the amp speaker outputs with their own 1/4 inch jacks.. would I be able to use this to connect both of the combo's speakers in SERIES (meaning 16 ohm load) to the 8 ohm speaker output?

 

[noth]

Re: impedance issues

I'd like to use my stereo 2x12 combo along with an 8 ohm 4x12 extension cab.. the combo itself has 2 50 watt/ 8 ohm speaker outputs which normally connect to each of the 8 ohm speakers built into the combo.. so I need to combine the two 8 ohm speakers of the combo in SERIES so that I can plug them into one of the 8 ohm speaker outputs and have the other speaker output connected to the extension cab.. the former being a safe mismatch (8 ohms into a 16 ohm load) and the latter being a perfect match... each of the combo speakers connect to the amp speaker outputs with their own 1/4 inch jacks.. would I be able to use this to connect both of the combo's speakers in SERIES (meaning 16 ohm load) to the 8 ohm speaker output?

NO, do not use this connector. It parallels the inputs resulting in a reduced impedance, so your 2 combo speakers of 8 ohms each will end up as 4 ohms with this adapter. You'll have to rewire your combo speakers in series (daisy chained) and then into a single phone plug. Or, make a box with 2 in, 1 out that will wire up the 2 in series, but that's kind of involved. That will give you the 16 ohms you're looking for. Then you can plug in your extension cab as you describe.

Noth

 

[rainsong86]

Re: impedance issues

NO, do not use this connector. It parallels the inputs resulting in a reduced impedance, so your 2 combo speakers of 8 ohms each will end up as 4 ohms with this adapter. You'll have to rewire your combo speakers in series (daisy chained) and then into a single phone plug. Or, make a box with 2 in, 1 out that will wire up the 2 in series, but that's kind of involved. That will give you the 16 ohms you're looking for. Then you can plug in your extension cab as you describe.

Noth

yea I figured something was fishy.. I still don't understand why this connector parallels the input (resulting in half the impedance of my individual speakers and thus pushing the amp past its capacity).. there aren't any similar connectors which put things in series?.. I'm completely foreign to this stuff because I simply don't mess around with hot signals, only line-level signals up until now

also.. I'm thinking about throwing out the entire idea.. won't the performance of my rig be degraded if I'm pushing a 16 ohm speaker with an amp running at 8 ohms?.. what does this do?.. doesn't it decrease the overall volume.. if so to what degree?

thanks, Kent

 

[noth]

Re: impedance issues

yea I figured something was fishy.. I still don't understand why this connector parallels the input (resulting in half the impedance of my individual speakers and thus pushing the amp past its capacity).. there aren't any similar connectors which put things in series?.. I'm completely foreign to this stuff because I simply don't mess around with hot signals, only line-level signals up until now

also.. I'm thinking about throwing out the entire idea.. won't the performance of my rig be degraded if I'm pushing a 16 ohm speaker with an amp running at 8 ohms?.. what does this do?.. doesn't it decrease the overall volume.. if so to what degree?

thanks, Kent

Well, phone jacks were actually meant to be just line level connectors. How they made their way into speaker cabinets was someone's bad idea - they're not really made to handle power. Anyway, so at line level that adapter is used to sum two signals into one. I don't think you'll find one that "series" them.

The 16 ohm load won't hurt the amp. You'll have somewhat less power, but you've got to try it to determine what it does to the sound.

Noth